The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform

Ian A. Johnston - One of the best experts on this subject based on the ideXlab platform.

  • Duplication of a Single myhz1.1 Gene Facilitated the Ability of Goldfish (Carassius auratus) to Alter Fast Muscle Contractile Properties With Seasonal Temperature Change.
    Frontiers in physiology, 2018
    Co-Authors: Daniel Garcia De La Serrana, Kristin M. Wreggelsworth, Ian A. Johnston
    Abstract:

    Seasonal temperature changes markedly effect the swimming performance of some cyprinid fish acutely tested at different temperatures, involving a restructuring of skeletal Muscle phenotype including changes in contractile properties and myosin heavy chain expression. We analyzed the transcriptome of Fast myotomal Muscle from goldfish (Carassius auratus L.) acclimated to either 8 or 25°C for 4 weeks (12 h light: 12 h dark) and identified 10 myosin heavy chains (myh) and 13 myosin light chain (myl) transcripts. Goldfish orthologs were classified based on zebrafish nomenclature as myhz1.1α, myhz1.1β, myhz1.1γ, myha, myhb, embryo_myh1, myh9b, smyh2, symh3, and myh11 (myosin heavy chains) and myl1a, myl1b, myl2, myl9a, myl9b, myl3, myl13, myl6, myl12.1a, myl12.1b, myl12.2a, myl12.2b, and myl10 (myosin light chains). The most abundantly expressed transcripts myhz1.1α, myhz1.1β, myhz1.1γ, myha, myl1a, myl1b, myl2, and myl3) were further investigated in Fast skeletal Muscle of goldfish acclimated to either 4, 8, 15, or 30°C for 12 weeks (12 h light:12 h dark). Total copy number for the myosin heavy chains showed a distinct optimum at 15°C (P < 0.01). Together myhz1.1α and myhz1.1β comprised 90 to 97% of myhc transcripts below 15°C, but only 62% at 30°C. Whereas myhz1.1α and myhz1.1β were equally abundant at 4 and 8°C, myhz1.1β transcripts were 17 and 12 times higher than myhz1.1α at 15 and 30°C, respectively, (P < 0.01). Myhz1.1γ expression was at least nine-fold higher at 30°C than at cooler temperatures (P < 0.01). In contrast, the expression of myha and myosin light chains showed no consistent pattern with acclimation temperature. A phylogenetic analysis indicated that the previously reported ability of goldfish and common carp to alter contractile properties and myofibrillar ATPase activity with temperature acclimation was related to the duplication of a single myhz1.1 Fast Muscle myosin heavy chain found in basal cyprinids such as the zebrafish (Danio rerio).

  • Table_4_Duplication of a Single myhz1.1 Gene Facilitated the Ability of Goldfish (Carassius auratus) to Alter Fast Muscle Contractile Properties With Seasonal Temperature Change.DOCX
    2018
    Co-Authors: Daniel Garcia De La Serrana, Kristin M. Wreggelsworth, Ian A. Johnston
    Abstract:

    Seasonal temperature changes markedly effect the swimming performance of some cyprinid fish acutely tested at different temperatures, involving a restructuring of skeletal Muscle phenotype including changes in contractile properties and myosin heavy chain expression. We analyzed the transcriptome of Fast myotomal Muscle from goldfish (Carassius auratus L.) acclimated to either 8 or 25°C for 4 weeks (12 h light: 12 h dark) and identified 10 myosin heavy chains (myh) and 13 myosin light chain (myl) transcripts. Goldfish orthologs were classified based on zebrafish nomenclature as myhz1.1α, myhz1.1β, myhz1.1γ, myha, myhb, embryo_myh1, myh9b, smyh2, symh3, and myh11 (myosin heavy chains) and myl1a, myl1b, myl2, myl9a, myl9b, myl3, myl13, myl6, myl12.1a, myl12.1b, myl12.2a, myl12.2b, and myl10 (myosin light chains). The most abundantly expressed transcripts myhz1.1α, myhz1.1β, myhz1.1γ, myha, myl1a, myl1b, myl2, and myl3) were further investigated in Fast skeletal Muscle of goldfish acclimated to either 4, 8, 15, or 30°C for 12 weeks (12 h light:12 h dark). Total copy number for the myosin heavy chains showed a distinct optimum at 15°C (P < 0.01). Together myhz1.1α and myhz1.1β comprised 90 to 97% of myhc transcripts below 15°C, but only 62% at 30°C. Whereas myhz1.1α and myhz1.1β were equally abundant at 4 and 8°C, myhz1.1β transcripts were 17 and 12 times higher than myhz1.1α at 15 and 30°C, respectively, (P < 0.01). Myhz1.1γ expression was at least nine-fold higher at 30°C than at cooler temperatures (P < 0.01). In contrast, the expression of myha and myosin light chains showed no consistent pattern with acclimation temperature. A phylogenetic analysis indicated that the previously reported ability of goldfish and common carp to alter contractile properties and myofibrillar ATPase activity with temperature acclimation was related to the duplication of a single myhz1.1 Fast Muscle myosin heavy chain found in basal cyprinids such as the zebrafish (Danio rerio).

  • insulin like growth factor igf signalling and genome wide transcriptional regulation in Fast Muscle of zebrafish following a single satiating meal
    The Journal of Experimental Biology, 2011
    Co-Authors: Ian P G Amaral, Ian A. Johnston
    Abstract:

    Male zebrafish (Danio rerio) were Fasted for 7 days and fed to satiation over 3 h to investigate the transcriptional responses to a single meal. The intestinal content at satiety (6.3% body mass) decreased by 50% at 3 h and 95% at 9 h following food withdrawal. Phosphorylation of the insulin-like growth factor (IGF) signalling protein Akt peaked within 3 h of feeding and was highly correlated with gut fullness. Retained paralogues of IGF hormones genes were regulated with feeding, with igf1a showing a pronounced peak in expression after 3 h and igf2b after 6 h. Igf-I receptor transcripts were markedly elevated with Fasting, and decreased to their lowest levels 45 min after feeding. igf1rb transcripts increased more quickly than igf1ra transcripts as the gut emptied. Paralogues of the insulin-like growth factor binding proteins (IGFBPs) were constitutively expressed, except for igfbp1a and igfbp1b transcripts, which were significantly elevated with Fasting. Genome-wide transcriptional responses were analysed using the Agilent 44K oligonucleotide microarray and selected genes validated by qPCR. Fasting was associated with the upregulation of genes for the ubiquitin-proteasome degradation pathway, anti-proliferative and pro-apoptotic genes. Protein chaperones (unc45b, hspd1, hspa5, hsp90a.1, hsp90a.2) and chaperone interacting proteins (ahsa1 and stip1) were upregulated 3 h after feeding along with genes for the initiation of protein synthesis and mRNA processing. Transcripts for the enzyme ornithine decarboxylase 1 showed the largest increase with feeding (11.5-fold) and were positively correlated with gut fullness. This study demonstrates the Fast nature of the transcriptional responses to a meal and provides evidence for differential regulation of retained paralogues of IGF signalling pathway genes.

  • activity of aspargate cathepsin d cysteine proteases cathepsins b b l and h and matrix metallopeptidase collagenase and their influence on protein and water holding capacity of Muscle in commercially farmed atlantic halibut hippoglossus hippoglossus
    Journal of Agricultural and Food Chemistry, 2008
    Co-Authors: Orjan Hagen, Christel Solberg, Ian A. Johnston
    Abstract:

    Atlantic halibut (Hippoglossus hippoglossus L.) were commercially farmed in Helgeland, Norway (May 2004−May 2005). The average weight (Mb) of fish increased over the 12 month production cycle by ∼73% for females and ∼50% for males, although during the winter months (November−early May) Mb was unchanged in females and declined by 18% in males because of sexual maturation and sperm release. Periods of zero or negative growth were associated with up to 5.7% (females) and 17.9% (males) decline in Fast Muscle protein content. The activities of cathepsins B, B + L, H, and D showed a reciprocal relationship and were highly correlated with the changes in protein content. Water-holding capacity was measured as the liquid loss increased from 3−5% in November to 11−13% in May. Two general additive models (GAMs) showed that cathepsin B + L, cathepsin D, and collagenase explained 73.1% of the total variance in protein content, while cathepsin H was the largest contributor to liquid loss, explaining ∼48.8% of the total...

  • activity of aspargate cathepsin d cysteine proteases cathepsins b b l and h and matrix metallopeptidase collagenase and their influence on protein and water holding capacity of Muscle in commercially farmed atlantic halibut hippoglossus hippoglossus
    Journal of Agricultural and Food Chemistry, 2008
    Co-Authors: Orjan Hagen, Christel Solberg, Ian A. Johnston
    Abstract:

    Atlantic halibut (Hippoglossus hippoglossus L.) were commercially farmed in Helgeland, Norway (May 2004-May 2005). The average weight (Mb) of fish increased over the 12 month production cycle by approximately 73% for females and approximately 50% for males, although during the winter months (November-early May) Mb was unchanged in females and declined by 18% in males because of sexual maturation and sperm release. Periods of zero or negative growth were associated with up to 5.7% (females) and 17.9% (males) decline in Fast Muscle protein content. The activities of cathepsins B, B + L, H, and D showed a reciprocal relationship and were highly correlated with the changes in protein content. Water-holding capacity was measured as the liquid loss increased from 3-5% in November to 11-13% in May. Two general additive models (GAMs) showed that cathepsin B + L, cathepsin D, and collagenase explained 73.1% of the total variance in protein content, while cathepsin H was the largest contributor to liquid loss, explaining approximately 48.8% of the total variance. The results indicate that to obtain the best flesh quality Atlantic halibut should be harvested in the fall or early winter when the liquid loss and cathepsin activities are low and less likely to cause problems during secondary processing and storage.

Simon M Hughes - One of the best experts on this subject based on the ideXlab platform.

  • myogenin promotes myocyte fusion to balance fibre number and size
    Nature Communications, 2018
    Co-Authors: Massimo Ganassi, Huascar Pedro Ortuste Quiroga, Sara Badodi, Yaniv Hinits, Peter S Zammit, Simon M Hughes
    Abstract:

    Each skeletal Muscle acquires its unique size before birth, when terminally differentiating myocytes fuse to form a defined number of multinucleated myofibres. Although mice in which the transcription factor Myogenin is mutated lack most myogenesis and die perinatally, a specific cell biological role for Myogenin has remained elusive. Here we report that loss of function of zebrafish myog prevents formation of almost all multinucleated Muscle fibres. A second, Myogenin-independent, fusion pathway in the deep myotome requires Hedgehog signalling. Lack of Myogenin does not prevent terminal differentiation; the smaller myotome has a normal number of myocytes forming more mononuclear, thin, albeit functional, Fast Muscle fibres. Mechanistically, Myogenin binds to the myomaker promoter and is required for expression of myomaker and other genes essential for myocyte fusion. Adult myog mutants display reduced Muscle mass, decreased fibre size and nucleation. Adult-derived myog mutant myocytes show persistent defective fusion ex vivo. Myogenin is therefore essential for Muscle homeostasis, regulating myocyte fusion to determine both Muscle fibre number and size.

  • signals and myogenic regulatory factors restrict pax3 and pax7 expression to dermomyotome like tissue in zebrafish
    Developmental Biology, 2007
    Co-Authors: Christina L Hammond, Yaniv Hinits, Daniel P S Osborn, James E N Minchin, Gianluca Tettamanti, Simon M Hughes
    Abstract:

    Pax3/7 paired homeodomain transcription factors are important markers of Muscle stem cells. Pax3 is required upstream of myod for lateral dermomyotomal cells in the amniote somite to form particular Muscle cells. Later Pax3/7-dependent cells generate satellite cells and most body Muscle. Here we analyse early myogenesis from, and regulation of, a population of Pax3-expressing dermomyotome-like cells in the zebrafish. Zebrafish pax3 is widely expressed in the lateral somite and, along with pax7, becomes restricted anteriorly and then to the external cells on the lateral somite surface. Midline-derived Hedgehog signals appear to act directly on lateral somite cells to repress Pax3/7. Both Hedgehog and Fgf8, signals that induce Muscle formation within the somite, suppress Pax3/7 and promote expression of myogenic regulatory factors (MRFs) myf5 and myod in specific Muscle precursor cell populations. Loss of MRF function leads to loss of myogenesis by specific populations of Muscle fibres, with parallel up-regulation of Pax3/7. Myod is required for lateral Fast Muscle differentiation from pax3-expressing cells. In contrast, either Myf5 or Myod is sufficient to promote slow Muscle formation from adaxial cells. Thus, myogenic signals act to drive somite cells to a myogenic fate through up-regulation of distinct combinations of MRFs. Our data show that the relationship between Pax3/7 genes and myogenesis is evolutionarily ancient, but that changes in the MRF targets for particular signals contribute to myogenic differences between species.

  • fgf8 drives myogenic progression of a novel lateral Fast Muscle fibre population in zebrafish
    Development, 2005
    Co-Authors: Julie A Groves, Christina L Hammond, Simon M Hughes
    Abstract:

    Fibroblast growth factors (Fgfs) have long been implicated in regulating vertebrate skeletal Muscle differentiation, but their precise role(s) in vivo remain unclear. Here, we show that Fgf8 signalling in the somite is required for myod expression and terminal differentiation of a subset of Fast Muscle cells in the zebrafish lateral somite. In the absence of Fgf8, lateral somite cells transiently express myf5 but fail to make Muscle and remain in a dermomyotome-like state characterised by pax3 and meox expression. Slow Muscle fibres form and commence normal migration in the absence of Fgf8, but fail to traverse the expanded undifferentiated lateral somite. The Fgf8-independent residual population of medial Fast Muscle fibres is not Hedgehog dependent. However, Fgf8-independent medial Fast Muscle precursors are lacking in floatinghead mutants, suggesting that they require another ventral midline-derived signal. We conclude that Fgf8 drives terminal differentiation of a specific population of lateral Muscle precursor cells within the early somite.

  • myogenin induces a shift of enzyme activity from glycolytic to oxidative metabolism in Muscles of transgenic mice
    Journal of Cell Biology, 1999
    Co-Authors: Simon M Hughes, Maggie M Y Chi, Oliver H Lowry, Kristian Gundersen
    Abstract:

    Physical training regulates Muscle metabolic and contractile properties by altering gene expression. Electrical activity evoked in Muscle fiber membrane during physical activity is crucial for such regulation, but the subsequent intracellular pathway is virtually unmapped. Here we investigate the ability of myogenin, a Muscle-specific transcription factor strongly regulated by electrical activity, to alter Muscle phenotype. Myogenin was overexpressed in transgenic mice using regulatory elements that confer strong expression confined to differentiated post-mitotic Fast Muscle fibers. In Fast Muscles from such mice, the activity levels of oxidative mitochondrial enzymes were elevated two- to threefold, whereas levels of glycolytic enzymes were reduced to levels 0.3–0.6 times those found in wild-type mice. Histochemical analysis shows widespread increases in mitochondrial components and glycogen accumulation. The changes in enzyme content were accompanied by a reduction in fiber size, such that many fibers acquired a size typical of oxidative fibers. No change in fiber type-specific myosin heavy chain isoform expression was observed. Changes in metabolic properties without changes in myosins are observed after moderate endurance training in mammals, including humans. Our data suggest that myogenin regulated by electrical activity may mediate effects of physical training on metabolic capacity in Muscle.

  • myogenin induces a shift of enzyme activity from glycolytic to oxidative metabolism in Muscles of transgenic mice
    Journal of Cell Biology, 1999
    Co-Authors: Simon M Hughes, Oliver H Lowry, Kristian Gundersen
    Abstract:

    Physical training regulates Muscle metabolic and contractile properties by altering gene expression. Electrical activity evoked in Muscle fiber membrane during physical activity is crucial for such regulation, but the subsequent intracellular pathway is virtually unmapped. Here we investigate the ability of myogenin, a Muscle-specific transcription factor strongly regulated by electrical activity, to alter Muscle phenotype. Myogenin was overexpressed in transgenic mice using regulatory elements that confer strong expression confined to differentiated post-mitotic Fast Muscle fibers. In Fast Muscles from such mice, the activity levels of oxidative mitochondrial enzymes were elevated two- to threefold, whereas levels of glycolytic enzymes were reduced to levels 0.3–0.6 times those found in wild-type mice. Histochemical analysis shows widespread increases in mitochondrial components and glycogen accumulation. The changes in enzyme content were accompanied by a reduction in fiber size, such that many fibers acquired a size typical of oxidative fibers. No change in fiber type-specific myosin heavy chain isoform expression was observed. Changes in metabolic properties without changes in myosins are observed after moderate endurance training in mammals, including humans. Our data suggest that myogenin regulated by electrical activity may mediate effects of physical training on metabolic capacity in Muscle.

Shugo Watabe - One of the best experts on this subject based on the ideXlab platform.

  • Multiple transcription factors mediating the expressional regulation of myosin heavy chain gene involved in the indeterminate Muscle growth of fish.
    Gene, 2018
    Co-Authors: A.k. Shakur Ahammad, Asaduzzaman, Shugo Watabe, Shuichi Asakawa, Saltuk Buğrahan Ceyhun, Hamid Ceylan, Shigeharu Kinoshita
    Abstract:

    Abstract Torafugu myosin heavy chain gene, MYHM2528–1, is specifically expressed in neonatal slow and Fast Muscle fibers, suggesting its functional role in indeterminate Muscle growth in fish. However, the transcriptional regulatory mechanisms of MYHM2528–1 involved in indeterminate Muscle growth in fish remained unknown. We previously isolated a 2100 bp 5′- flanking sequence of torafugu MYHM2528–1 that showed sufficient promoter activity to allow specific gene expression in neonatal Muscle fibers of zebrafish. Here, we examined the cis-regulatory mechanism of 2100 bp 5′-flanking region of torafugu MYHM2528–1 using deletion-mutation analysis in zebrafish embryo. We discovered that myoblast determining factor (MyoD) binding elements play a key role and participate in the transcriptional regulation of MYHM2528–1 expression in zebrafish embryos. We further discovered that paired box protein (Pax3) are required for promoting MYHM2528–1 expression and myocyte enhancer factor-2 (MEF2) binding sites participate in the transcriptional regulation of MYHM2528–1 expression in slow/Fast skeletal Muscles. Our study also confirmed that the nuclear factor of activated T-cell (NFAT) binding sites take part in the transcriptional regulation of MYHM2528–1 expression in slow and Fast Muscles fiber in relation to indeterminate Muscle growth. These results obviously confirmed that multiple cis-elements in the 5′-flanking region of MYHM2528–1 function in the transcriptional regulation of its expression.

  • promoter analysis of the fish gene of slow cardiac type myosin heavy chain implicated in specification of Muscle fiber types
    Fish Physiology and Biochemistry, 2018
    Co-Authors: Shigeharu Kinoshita, Dadasaheb B. Akolkar, Shuichi Asakawa, Saltuk Buğrahan Ceyhun, Bhuiyan Sharmin Siddique, Shugo Watabe
    Abstract:

    Vertebrate skeletal Muscles consist of heterogeneous tissues containing various types of Muscle fibers, where specification of the fiber type is crucial for Muscle development. Fish are an attractive experimental model to study the mechanisms of such fiber type specification because of the separated localization of slow and Fast Muscles in the trunk myotome. We examined regulation of expression of the torafugu gene of slow/cardiac-type myosin heavy chain, MYH M5 , and isolated an operational promoter in order to force its tissue-specific expression across different fish species via the transgenic approach in zebrafish and medaka. This promoter activity was observed in adaxial cell-derived superficial slow Muscle fibers under the control of a hedgehog signal. We also uncovered coordinated expression of MYH M5 and Sox6b, which is an important transcriptional repressor for specification of Muscle fiber types and participates in hedgehog signaling. Sequence comparison in the 5′-flanking region identified three conserved regions, CSR1–CSR3, between torafugu MYH M5 and its zebrafish ortholog. Analysis of deletion mutants showed that CSR1 significantly stimulates gene expression in slow Muscle fibers. In contrast, deletion of CSR3 resulted in ectopic expression of a reporter gene in Fast Muscle fibers. CSR3 was found to contain a putative Sox family protein-binding site. These results indicate that the dual mechanism causing inhibition in Fast Muscle fibers and activation in slow Muscle fibers is essential for slow Muscle fiber-specific gene expression in fish.

  • 5 flanking sequences of zebrafish Fast myosin heavy chain genes regulate unique expression in the anterior medial subsection and posterior tail somites of the skeletal Muscle
    Comparative Biochemistry and Physiology B, 2016
    Co-Authors: M Asaduzzaman, Shigeharu Kinoshita, Shugo Watabe, Shuichi Asakawa, A.k. Shakur Ahammad
    Abstract:

    In zebrafish, Fast Muscle-specific myosin heavy chain genes have their unique expression patterns in a well-defined and restricted region of the skeletal Muscle. However, the transcriptional regulatory mechanisms involved have remained unclear. Here, we examined the regulation of spatio-temporal expression patterns of myhz1 (myhz1.1, myhz1.2 and myhz1.3) and myhz2 during their development by using transient gene and stable transgenic techniques. Embryos microinjected with different length 5'-flanking sequences of myhz1 conjugated with the enhanced green fluorescent protein (EGFP) gene showed EGFP expression in the anterior and medial subsections of somites, but not in the tail somite region. In contrast, embryos microinjected with different length 5'-flanking sequences of myhz2 showed EGFP expression exclusively at the posterior tail somite domain. Promoter deletion analyses demonstrated that reduced EGFP fluorescence typically is correlated with smaller 5'-flanking sequences. The immunohistochemical observation revealed that zebrafish larvae provided with the transient gene and those from stable transgenic lines consistently expressed EGFP in the Fast Muscle fibers. r-VISTA plot identified one common conserved region of about 140°bp among myhz1.1, myhz1.2 and myhz1.3. Deletion of this conserved region from the 5'-flanking sequence of each myhz1 markedly reduced EGFP expression in its unique spatial somite region. Deletion mutation analysis demonstrated that myhz2 expression in the tail somite region might be mediated by Tbx (family of transcription factors having a common DNA-binding sequence known as T-box) binding elements. In summary, 5'-flanking sequences of myhz1 and myhz2 regulate their unique expression patterns in a well-defined and restricted somite region of the skeletal Muscle in zebrafish.

  • Regulation of gene expression mediating indeterminate Muscle growth in teleosts.
    Mechanisms of development, 2015
    Co-Authors: A.k. Shakur Ahammad, Shugo Watabe, Asaduzzaman, Shuichi Asakawa, Shigeharu Kinoshita
    Abstract:

    Abstract Teleosts are unique among vertebrates due to their indeterminate Muscle growth, i.e., continued production of neonatal Muscle fibers until death. However, the molecular mechanism(s) underlying this property is unknown. Here, we focused on the torafugu ( Takifugu rubripes ) myosin heavy chain gene, MYH M2528-1 , which is specifically expressed in neonatal Muscle fibers produced by indeterminate Muscle growth. We examined the flanking region of MYH M2528-1 through an in vivo reporter assay using zebrafish ( Danio rerio ) and identified a 2100 bp 5′-flanking sequence that contained sufficient promoter activity to allow specific gene expression. The effects of enhanced promoter activity were observed at the outer region of the Fast Muscle and the dorsal edge of slow Muscle in zebrafish larvae. At the juvenile stage, the promoter was specifically activated in small diameter Muscle fibers scattered throughout Fast Muscle and in slow Muscle near the septum separating slow and Fast Muscles. This spatio-temporal promoter activity overlapped with known myogenic zones involved in teleost indeterminate Muscle growth. A deletion mutant analysis revealed that the −2100 to −600 bp 5′flanking sequence of MYH M2528-1 is essential for promoter activity. This region contains putative binding sites for several representative myogenesis-related transcription factors and nuclear factor of activated T-cell (NFAT), a transcription activator involved in regeneration of mammalian adult skeletal Muscle. A significant reduction in the promoter activity of the MYH M2528-1 deletion constructs was observed in accordance with a reduction in the number of these binding sites, suggesting the involvement of specific transcription factors in indeterminate Muscle growth.

  • the occurrence of two types of Fast skeletal myosin heavy chains from abdominal Muscle of kuruma shrimp marsupenaeus japonicus and their different tissue distribution
    The Journal of Experimental Biology, 2012
    Co-Authors: Hiroki Koyama, Dadasaheb Akolkar, Takafumi Shiokai, Misako Nakaya, Sanit Piyapattanakorn, Shugo Watabe
    Abstract:

    SUMMARY Shrimps belong to the class Crustacea, which forms a large, diverse group in the invertebrates. However, the physiology and biochemistry of their skeletal Muscles have been poorly understood compared with those from vertebrates including mammals and fish. The present study focused on myosin, the major protein in skeletal Muscle, from adult specimens of kuruma shrimp Marsupenaeus japonicus. Two types of the gene encoding myosin heavy chain (MHC), a large subunit of the myosin molecule, were cloned from abdominal Fast skeletal Muscle and defined as MHCa and MHCb. Protein analysis revealed that the MHCa isoform was expressed at a higher level than the MHCb isoform. The full-length cDNA clones of MHCa and MHCb consisted of 5929 bp and 5955 bp, respectively, which encoded 1912 and 1910 amino acids, respectively. Both were classified into Fast Muscle type by comparison with the partially deduced amino acid sequences of Fast-type and slow-type (S1, slow twitch) MHCs reported previously for the American lobster Homarus americanus. The amino acid identities between MHCa and MHCb of kuruma shrimp were 78%, 60% and 72% in the regions of subfragment-1, subfragment-2 and light meromyosin, respectively, and 71% in total. In situ hybridisation using anti-sense RNA-specific probes, along with northern blot analysis using different tissues from abdominal Muscle, revealed the different localisation of MHCa and MHCb transcripts in abdominal Fast skeletal Muscle, suggesting their distinct physiological functions.

Orjan Hagen - One of the best experts on this subject based on the ideXlab platform.

  • growth performance Fast Muscle development and chemical composition of juvenile lumpfish cyclopterus lumpus fed diets incorporating soy and pea protein concentrates
    Aquaculture Reports, 2020
    Co-Authors: Florence Perera Willora, Nimalan Nadanasabesan, Helene Ronquist Knutsen, Cui Liu, Mette Sorensen, Orjan Hagen
    Abstract:

    Abstract Lumpfish (Cyclopterus lumpus) are widely applied as biological delousers in open net-pen farming of Atlantic salmon. As a species new to farming it is necessary to obtain a comprehensive understanding of the capacity of lumpfish to utilize plant derived feed ingredients. A feeding trial lasting for 54 days was conducted to investigate the effects of replacing fishmeal (FM) with a mix of soy protein concentrate (SPC) and pea protein concentrate (PPC) on growth, body chemical composition, and Fast Muscle fiber cellularity in juvenile lumpfish. Four isonitrogenous and isoenergetic diets (52 % crude protein and 14 % crude lipid) were formulated; a FM based diet was used as control (CTRL), and three experimental diets containing SPC and PPC (equal proportions of 1:1), replacing FM on weight basis at 25 % (PP25) 50 % (PP50) and 75 % (PP75). The fish grew from approximately 6.9 g to an average weight of 40.2 g in 54 days. Fish fed PP50 had significantly higher body weight, length and height compared to the other dietary groups. The whole body crude protein content of fish fed PP50 was significantly higher compared to the CTRL diet, while crude lipids were lower than those on CTRL and PP25 diets. Ash and dry matter did not differ among groups. Probability density functions showed no differences in Fast Muscle fiber size distributions amongst feeding groups. A higher percentage of smaller fibers in all feeding groups indicated hyperplasia was the dominant mechanism of Muscle growth during the experimental period. These results suggest that a mixture of SPC and PPC can replace up to 50 % of FM in diets for juvenile lumpfish without any adverse effects on growth, chemical composition and Fast Muscle fiber cellularity.

  • Muscle growth and changes in chemical composition of spotted wolffish juveniles (Anarhichas minor) fed diets with and without microalgae (Scenedesmus obliquus)
    Elsevier, 2019
    Co-Authors: Helene Ronquist Knutsen, Mette Sorensen, O.h. Ottesen, A.m. Palihawadana, W. Sandaa, Orjan Hagen
    Abstract:

    Spotted wolffish (Anarhichas minor) is a promising new candidate for cold-water fish farming, but knowledge is needed about its physiology and its capacity to utilize alternative feed ingredients. The aim of the study was to investigate Fast Muscle growth dynamics, changes in chemical composition as well as growth performance of spotted wolffish when fed diets with or without the microalgae Scenedesmus obliquus incorporated. Juvenile spotted wolffish were fed four diets containing fishmeal as the primary source of protein (CTR diet) or microalgae (Scenedesmus obliquus) replacing 4% (AL4 diet), 8% (AL8 diet) or 12% (AL12 diet) of the fishmeal. During the 12 week experiment, fish grew from an average weight of 140 g to 250 g. The results showed indications of Fast Muscle cellularity of spotted wolffish being affected by dietary algae inclusion as the control and AL4 groups appeared to be more strongly favored by hypertrophic growth compared to the AL8 and AL12 groups. The CTR and AL4 groups tended towards increased Muscle fiber diameters and higher proportions of larger Muscle fibers, while the AL8 and AL12 group tended towards similar or increased proportions of smaller Muscle fibers at the end of the trial. Probability density functions showed no difference in Fast Muscle fiber size distributions between dietary groups. Muscle crude protein and fat content tended to increase with growth in all treatment groups and Muscle mineral content was reduced in all groups fed diets containing Scenedesmus. At the end of the trial, hepatosomatic index was reduced in all treatment groups. Dietary replacement of fishmeal with Scenedesmus also affected skin coloration, with increasing yellowness observed with increasing microalgae replacement. This study indicates that spotted wolffish has the potential to use microalgae as an alternative to fishmeal in the diet. Keywords: nutrition, sustainable aquafeed, Muscle fiber cellularity, Muscle growth, proximate composition, histology, alternative feed ingredient

  • growth and Muscle cellularity of diploid and triploid atlantic cod gadus morhua linnaeus 1758 larvae
    Journal of Applied Ichthyology, 2015
    Co-Authors: Cecilia Campos Vargas, Stefano Peruzzi, Orjan Hagen
    Abstract:

    Summary The aim of this study was to compare somatic growth and Muscle fibre development in diploid and triploid siblings of Atlantic cod (Gadus morhua Linnaeus, 1758) during the larval stage. Newly hatched larvae were transferred into 200-L tanks, three tanks per ploidy group (70 larvae L−1, continuous light, gradually increasing seawater temperature 7–11°C and flow rates 50–117 L h−1). Larvae were fed rotifers from 2 to 22 days post hatch (dph), Artemia 19–31 dph and weaned onto a microparticulate diet from 26 dph until the end of the experiment. Measurements of growth (dry weight, standard length) and Muscle cellullarity were taken at intervals between 1 and 44 dph. Ploidy groups showed a similar performance throughout the trial, although a marked stagnation in growth was observed for triploids during the weaning from Artemia onto dry feed. Overall, diploid and triploid cod larvae showed a similar development in Muscle fibre growth pattern during the experimental period. For both groups, the total number of Fast Muscle fibres showed a 10-fold increase (from 384 to 3462), whereas the diameter of Fast fibre increased from 8.9 to 13.3 μm (mean number from all treatments). Thus, a temporary but significant effect of triploidy on Fast Muscle fibre growth pattern was observed in 19 dph larvae in terms of fibre size and number, with triploids showing larger mean Fast fibre diameter (11.62 ± 0.63 vs. 10.05 ± 0.34) and a lower number of fibres with a diameter <5 μm than their diploid siblings. Thus, this was found to be related to larvae size and to the differences in total Fast fibre cross sectional areas rather than to ploidy status. Overall, our results suggest possible deficiencies in nutrients’ digestion and absorption of triploid cod larvae particularly during the transitional period from live food to inert diets.

  • activity of aspargate cathepsin d cysteine proteases cathepsins b b l and h and matrix metallopeptidase collagenase and their influence on protein and water holding capacity of Muscle in commercially farmed atlantic halibut hippoglossus hippoglossus
    Journal of Agricultural and Food Chemistry, 2008
    Co-Authors: Orjan Hagen, Christel Solberg, Ian A. Johnston
    Abstract:

    Atlantic halibut (Hippoglossus hippoglossus L.) were commercially farmed in Helgeland, Norway (May 2004−May 2005). The average weight (Mb) of fish increased over the 12 month production cycle by ∼73% for females and ∼50% for males, although during the winter months (November−early May) Mb was unchanged in females and declined by 18% in males because of sexual maturation and sperm release. Periods of zero or negative growth were associated with up to 5.7% (females) and 17.9% (males) decline in Fast Muscle protein content. The activities of cathepsins B, B + L, H, and D showed a reciprocal relationship and were highly correlated with the changes in protein content. Water-holding capacity was measured as the liquid loss increased from 3−5% in November to 11−13% in May. Two general additive models (GAMs) showed that cathepsin B + L, cathepsin D, and collagenase explained 73.1% of the total variance in protein content, while cathepsin H was the largest contributor to liquid loss, explaining ∼48.8% of the total...

  • activity of aspargate cathepsin d cysteine proteases cathepsins b b l and h and matrix metallopeptidase collagenase and their influence on protein and water holding capacity of Muscle in commercially farmed atlantic halibut hippoglossus hippoglossus
    Journal of Agricultural and Food Chemistry, 2008
    Co-Authors: Orjan Hagen, Christel Solberg, Ian A. Johnston
    Abstract:

    Atlantic halibut (Hippoglossus hippoglossus L.) were commercially farmed in Helgeland, Norway (May 2004-May 2005). The average weight (Mb) of fish increased over the 12 month production cycle by approximately 73% for females and approximately 50% for males, although during the winter months (November-early May) Mb was unchanged in females and declined by 18% in males because of sexual maturation and sperm release. Periods of zero or negative growth were associated with up to 5.7% (females) and 17.9% (males) decline in Fast Muscle protein content. The activities of cathepsins B, B + L, H, and D showed a reciprocal relationship and were highly correlated with the changes in protein content. Water-holding capacity was measured as the liquid loss increased from 3-5% in November to 11-13% in May. Two general additive models (GAMs) showed that cathepsin B + L, cathepsin D, and collagenase explained 73.1% of the total variance in protein content, while cathepsin H was the largest contributor to liquid loss, explaining approximately 48.8% of the total variance. The results indicate that to obtain the best flesh quality Atlantic halibut should be harvested in the fall or early winter when the liquid loss and cathepsin activities are low and less likely to cause problems during secondary processing and storage.

Shigeharu Kinoshita - One of the best experts on this subject based on the ideXlab platform.

  • Multiple transcription factors mediating the expressional regulation of myosin heavy chain gene involved in the indeterminate Muscle growth of fish.
    Gene, 2018
    Co-Authors: A.k. Shakur Ahammad, Asaduzzaman, Shugo Watabe, Shuichi Asakawa, Saltuk Buğrahan Ceyhun, Hamid Ceylan, Shigeharu Kinoshita
    Abstract:

    Abstract Torafugu myosin heavy chain gene, MYHM2528–1, is specifically expressed in neonatal slow and Fast Muscle fibers, suggesting its functional role in indeterminate Muscle growth in fish. However, the transcriptional regulatory mechanisms of MYHM2528–1 involved in indeterminate Muscle growth in fish remained unknown. We previously isolated a 2100 bp 5′- flanking sequence of torafugu MYHM2528–1 that showed sufficient promoter activity to allow specific gene expression in neonatal Muscle fibers of zebrafish. Here, we examined the cis-regulatory mechanism of 2100 bp 5′-flanking region of torafugu MYHM2528–1 using deletion-mutation analysis in zebrafish embryo. We discovered that myoblast determining factor (MyoD) binding elements play a key role and participate in the transcriptional regulation of MYHM2528–1 expression in zebrafish embryos. We further discovered that paired box protein (Pax3) are required for promoting MYHM2528–1 expression and myocyte enhancer factor-2 (MEF2) binding sites participate in the transcriptional regulation of MYHM2528–1 expression in slow/Fast skeletal Muscles. Our study also confirmed that the nuclear factor of activated T-cell (NFAT) binding sites take part in the transcriptional regulation of MYHM2528–1 expression in slow and Fast Muscles fiber in relation to indeterminate Muscle growth. These results obviously confirmed that multiple cis-elements in the 5′-flanking region of MYHM2528–1 function in the transcriptional regulation of its expression.

  • promoter analysis of the fish gene of slow cardiac type myosin heavy chain implicated in specification of Muscle fiber types
    Fish Physiology and Biochemistry, 2018
    Co-Authors: Shigeharu Kinoshita, Dadasaheb B. Akolkar, Shuichi Asakawa, Saltuk Buğrahan Ceyhun, Bhuiyan Sharmin Siddique, Shugo Watabe
    Abstract:

    Vertebrate skeletal Muscles consist of heterogeneous tissues containing various types of Muscle fibers, where specification of the fiber type is crucial for Muscle development. Fish are an attractive experimental model to study the mechanisms of such fiber type specification because of the separated localization of slow and Fast Muscles in the trunk myotome. We examined regulation of expression of the torafugu gene of slow/cardiac-type myosin heavy chain, MYH M5 , and isolated an operational promoter in order to force its tissue-specific expression across different fish species via the transgenic approach in zebrafish and medaka. This promoter activity was observed in adaxial cell-derived superficial slow Muscle fibers under the control of a hedgehog signal. We also uncovered coordinated expression of MYH M5 and Sox6b, which is an important transcriptional repressor for specification of Muscle fiber types and participates in hedgehog signaling. Sequence comparison in the 5′-flanking region identified three conserved regions, CSR1–CSR3, between torafugu MYH M5 and its zebrafish ortholog. Analysis of deletion mutants showed that CSR1 significantly stimulates gene expression in slow Muscle fibers. In contrast, deletion of CSR3 resulted in ectopic expression of a reporter gene in Fast Muscle fibers. CSR3 was found to contain a putative Sox family protein-binding site. These results indicate that the dual mechanism causing inhibition in Fast Muscle fibers and activation in slow Muscle fibers is essential for slow Muscle fiber-specific gene expression in fish.

  • 5 flanking sequences of zebrafish Fast myosin heavy chain genes regulate unique expression in the anterior medial subsection and posterior tail somites of the skeletal Muscle
    Comparative Biochemistry and Physiology B, 2016
    Co-Authors: M Asaduzzaman, Shigeharu Kinoshita, Shugo Watabe, Shuichi Asakawa, A.k. Shakur Ahammad
    Abstract:

    In zebrafish, Fast Muscle-specific myosin heavy chain genes have their unique expression patterns in a well-defined and restricted region of the skeletal Muscle. However, the transcriptional regulatory mechanisms involved have remained unclear. Here, we examined the regulation of spatio-temporal expression patterns of myhz1 (myhz1.1, myhz1.2 and myhz1.3) and myhz2 during their development by using transient gene and stable transgenic techniques. Embryos microinjected with different length 5'-flanking sequences of myhz1 conjugated with the enhanced green fluorescent protein (EGFP) gene showed EGFP expression in the anterior and medial subsections of somites, but not in the tail somite region. In contrast, embryos microinjected with different length 5'-flanking sequences of myhz2 showed EGFP expression exclusively at the posterior tail somite domain. Promoter deletion analyses demonstrated that reduced EGFP fluorescence typically is correlated with smaller 5'-flanking sequences. The immunohistochemical observation revealed that zebrafish larvae provided with the transient gene and those from stable transgenic lines consistently expressed EGFP in the Fast Muscle fibers. r-VISTA plot identified one common conserved region of about 140°bp among myhz1.1, myhz1.2 and myhz1.3. Deletion of this conserved region from the 5'-flanking sequence of each myhz1 markedly reduced EGFP expression in its unique spatial somite region. Deletion mutation analysis demonstrated that myhz2 expression in the tail somite region might be mediated by Tbx (family of transcription factors having a common DNA-binding sequence known as T-box) binding elements. In summary, 5'-flanking sequences of myhz1 and myhz2 regulate their unique expression patterns in a well-defined and restricted somite region of the skeletal Muscle in zebrafish.

  • Regulation of gene expression mediating indeterminate Muscle growth in teleosts.
    Mechanisms of development, 2015
    Co-Authors: A.k. Shakur Ahammad, Shugo Watabe, Asaduzzaman, Shuichi Asakawa, Shigeharu Kinoshita
    Abstract:

    Abstract Teleosts are unique among vertebrates due to their indeterminate Muscle growth, i.e., continued production of neonatal Muscle fibers until death. However, the molecular mechanism(s) underlying this property is unknown. Here, we focused on the torafugu ( Takifugu rubripes ) myosin heavy chain gene, MYH M2528-1 , which is specifically expressed in neonatal Muscle fibers produced by indeterminate Muscle growth. We examined the flanking region of MYH M2528-1 through an in vivo reporter assay using zebrafish ( Danio rerio ) and identified a 2100 bp 5′-flanking sequence that contained sufficient promoter activity to allow specific gene expression. The effects of enhanced promoter activity were observed at the outer region of the Fast Muscle and the dorsal edge of slow Muscle in zebrafish larvae. At the juvenile stage, the promoter was specifically activated in small diameter Muscle fibers scattered throughout Fast Muscle and in slow Muscle near the septum separating slow and Fast Muscles. This spatio-temporal promoter activity overlapped with known myogenic zones involved in teleost indeterminate Muscle growth. A deletion mutant analysis revealed that the −2100 to −600 bp 5′flanking sequence of MYH M2528-1 is essential for promoter activity. This region contains putative binding sites for several representative myogenesis-related transcription factors and nuclear factor of activated T-cell (NFAT), a transcription activator involved in regeneration of mammalian adult skeletal Muscle. A significant reduction in the promoter activity of the MYH M2528-1 deletion constructs was observed in accordance with a reduction in the number of these binding sites, suggesting the involvement of specific transcription factors in indeterminate Muscle growth.

  • multiple cis elements in the 5 flanking region of embryonic larval Fast type of the myosin heavy chain gene of torafugu myhm743 2 function in the transcriptional regulation of its expression
    Gene, 2011
    Co-Authors: M Asaduzzaman, Shigeharu Kinoshita, Shuichi Asakawa, Bhuiyan Sharmin Siddique, Shugo Watabe
    Abstract:

    Abstract The myosin heavy chain gene, MYHM743-2, is highly expressed in Fast Muscle fibers of torafugu embryos and larvae, suggesting its functional roles for embryonic and larval Muscle development. However, the transcriptional regulatory mechanism involved in its expression remained unknown. Here, we analyzed the 2075 bp 5′-flanking region of torafugu MYHM743-2 to examine the spatial and temporal regulation by using transgenic and transient expression techniques in zebrafish embryos. Combining both transient and transgenic analyses, we demonstrated that the 2075 bp 5′-flanking sequences was sufficient for its expression in skeletal, craniofacial and pectoral fin Muscles. The immunohistochemical observation revealed that the zebrafish larvae from the stable transgenic line consistently expressed enhanced green fluorescent protein (EGFP) in Fast Muscle fibers. Promoter deletion analyses demonstrated that the minimum 468 bp promoter region could direct MYHM743-2 expression in zebrafish larvae. We discovered that the serum response factor (SRF)-like binding sites are required for promoting MYHM743-2 expression and myoblast determining factor (MyoD) and myocyte enhancer factor-2 (MEF2) binding sites participate in the transcriptional control of MYHM743-2 expression in Fast skeletal Muscles. We further discovered that MyoD binding sites, but not MEF2, participate in the transcriptional regulation of MYHM743-2 expression in pectoral fin and craniofacial Muscles. These results clearly demonstrated that multiple cis-elements in the 5′-flanking region of MYHM743-2 function in the transcriptional control of its expression.