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Barbara Stay - One of the best experts on this subject based on the ideXlab platform.
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evidence for a phe gly leu amide like allatostatin in the beetle tenebrio molitor
Peptides, 2010Co-Authors: Karen L Elliott, Kuen Kuen Chan, Barbara StayAbstract:The allatostatins (ASTs) with Phe-Gly-Leu-amide C-terminal sequence are multifunctional neuropeptides discovered as inhibitors of juvenile hormone (JH) synthesis by corpora allata (CA) of cockroaches. Although these ASTs inhibit JH synthesis only in cockroaches, crickets, termites and locusts, isolation of peptides or of cDNA/genomic DNA or analysis of genomes indicates their occurrence in many orders of insects with the exception of coleopterans. The gene for these ASTs has not been found in the genome of the red flour beetle Tribolium castaneum (Family Tenebrionidae). Yet, in view of widespread occurrence of these peptides in insects, crustaceans and nematodes, they would be expected to occur in beetles. This study provides evidence for the presence of FGLa-like ASTs in the tenebrionid beetle, Tenebrio molitor, and scarabid beetle, Popillia japonica. Extract of Brain from both beetles inhibited JH synthesis by cockroach CA dose dependently and reversibly. 20 Brain equivalents of T. molitor and P. japonica Extracts inhibited JH synthesis 64 ± 5 and 65 ± 0.6% respectively. Antibody against cockroach allatostatin (Diploptera punctata AST-7) used in an enzyme-linked immunosorbent assay reacted with Brain Extract of these beetles. Antibody against D. punctata AST-5 localized FGLa-like ASTs in the Brain and subesophageal ganglion of T. molitor and P. japonica. In addition, pretreatment of T. molitor Brain Extract with anti-D. punctata AST-5 reduced the inhibition of JH synthesis and pretreatment of anti-D. punctata AST-5 with D. punctata AST-5 diminished the immunoreactivity of the antibody. Thus we predict that FGLa-like allatostatins will be found in beetles.
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identification of phe gly leu amide type allatostatin 7 in reticulitermes flavipes its localization in tissues and relation to juvenile hormone synthesis
Peptides, 2009Co-Authors: Karen L Elliott, Lynn M Teesch, Kuen Kuen Chan, Omar Clor, Barbara StayAbstract:Abstract The allatostatins (ASTs), with a Tyr/Phe-Xaa-Phe-Gly-Leu/Ile-amide C-terminus, are neuropeptides that occur in many orders of insects, but are known to inhibit juvenile hormone (JH) synthesis by corpora allata (CA) only in cockroaches, crickets, and termites. 5 AST peptides with similar sequences to those of 6 species of cockroaches have been isolated and sequenced from Extract of Brain tissue of the termite Reticulitermes flavipes. The amino acid sequence of a 6th peptide, R. flavipes AST-7, determined by LC–MS/MS following HPLC fractionation of Brain Extract, is S-P-S-S-G-N-Q-R-L-Y-G-F-G-L-NH2. The 8 terminal amino acids are identical to AST-7 of the cockroach Diploptera punctata. R. flavipes and D. punctata AST-7s inhibited JH synthesis by CA of both species equally and their affinity for antibody against D. punctata AST-7 is similar. Immunoreactivity of termite tissue with this antibody indicates neuro- and myomodulatory activity of the peptide in addition to its demonstrated allatostatic function. The density of AST immunostaining in axons within the CA of R. flavipes and the rate of JH synthesis by similar glands were negatively correlated. This is evidence that when AST is abundant in the glands it is being released in vivo to limit JH production.
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isolation of cockroach phe gly leu amide allatostatins from the termite reticulitermes flavipes and their effect on juvenile hormone synthesis
Journal of Insect Physiology, 2008Co-Authors: Koichiro J Yagi, Stephen S Tobe, Karen L Elliott, Lynn M Teesch, Barbara StayAbstract:Immunoreactivity to cockroach Diploptera punctata allatostatin-7 (Dippu AST-7) has been demonstrated previously in axons innervating the corpora allata of the termite Reticulitermes flavipes. This peptide and Dippu AST-11 inhibited juvenile hormone (JH) synthesis by corpora allata (CA) of brachypterous neotenic reproductives (secondary reproductives) of termites. The present study shows that R. flavipes CA are also inhibited by Dippu AST-2, AST-5, AST-8, and AST-9 at approximately the same rank order of potency as demonstrated in D. punctata. Another allatostatin from Periplaneta americana (Peram AST-12) also inhibits JH synthesis by R. flavipes CA. Sensitivity to the allatostatins is higher in glands with low rates of JH synthesis than in those with relatively high JH synthetic rates as has been demonstrated in CA from male and female secondary reproductives as well as in those from non-egg-laying and egg-laying females. The identical inhibitory effects of R. flavipes Brain Extract on CA from both D. punctata and R. flavipes and the isolation and identification of five cockroach allatostatins (Dippu AST-1, AST-2, AST-5, AST-8, and Peram AST-12) from termite Brain Extract reflect the close relationship between cockroaches and termites.
Shin-ichi Hisanaga - One of the best experts on this subject based on the ideXlab platform.
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in vivo and in vitro phosphorylation at ser 493 in the glutamate e segment of neurofilament h subunit by glycogen synthase kinase 3β
Journal of Biological Chemistry, 2002Co-Authors: Takahiro Sasaki, Koichi Ishiguro, Taro Saito, Masato Taoka, Atsuko Uchida, Toshiaki Isobe, Shin-ichi HisanagaAbstract:Abstract Neurofilament (NF), a major neuronal intermediate filament, is composed of three subunits, NF-L, NF-M, and NF-H. All three subunits contain a well conserved glutamate (E)-rich region called “E-segment” in the N terminus of the tail region. Although the E-segments of NF-L and NF-M are phosphorylated by casein kinases, it has not been observed in NF-H. Using mass spectrometric analysis, we identified phosphorylation of the E-segment of NF-H, prepared from rat spinal cords, at Ser-493 and Ser-501 in the Ser-Pro sequences. The E-segment kinase was isolated from rat Brain Extract using column chromatography and identified as glycogen synthase kinase (GSK) 3β. GSK3β was shown to phosphorylate at Ser-493 in vitro by phosphopeptide mapping and site-directed mutagenesis, and in vivo in HEK293 cells using the phospho-Ser-493 antibody, but did not phosphorylate Ser-501. GSK3β preferred Ser-493 to the KSP-repeated sequences for phosphorylation sites in the NF-H tail domain. Moreover, Ser-493 was a better phosphorylation site for GSK3β than other proline-directed protein kinases, Cdk5/p35 and ERK. GSK3β in the spinal cord Extract was associated with NF cytoskeletons. Taken together, we concluded that Ser-493 in the E-segment of NF-H is phosphorylated by GSK3β in rat spinal cords.
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calpain dependent proteolytic cleavage of the p35 cyclin dependent kinase 5 activator to p25
Journal of Biological Chemistry, 2000Co-Authors: Genichi Kusakawa, Koichi Ishiguro, Reiko Onuki, Takeo Kishimoto, Taro Saito, Shin-ichi HisanagaAbstract:Abstract Cyclin-dependent kinase 5 (CDK5) is a unique CDK, the activity of which can be detected in postmitotic neurons. To date, CDK5 purified from mammalian Brains has always been associated with a truncated form of the 35-kDa major Brain specific activator (p35, also known as nck5a) of CDK5, known as p25. In this study, we report that p35 can be cleaved to p25 both in vitro and in vivo by calpain. In a rat Brain Extract, p35 was cleaved to p25 by incubation with Ca2+. This cleavage was inhibited by a calpain inhibitor peptide derived from calpastatin and was ablated by separating the p35·CDK5 from calpain by centrifugation. The p35 recovered in the pellet after centrifugation could then be cleaved to p25 by purified calpain. Cleavage of p35 was also induced in primary cultured neurons by treatment with a Ca2+ ionophore and Ca2+ and inhibited by calpain inhibitor I. The cleavage changed the solubility of the CDK5 active complex from the particulate fraction to the soluble fraction but did not affect the histone H1 kinase activity. Increased cleavage was detected in cultured neurons undergoing cell death, suggesting a role of the cleavage in neuronal cell death.
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porcine Brain neurofilament h tail domain kinase its identification as cdk5 p26 complex and comparison with cdc2 cyclin b kinase
Cytoskeleton, 1995Co-Authors: Shin-ichi Hisanaga, Koichi Ishiguro, Tsuneko Uchida, Massashi Uchiyama, Tomoko Hosoi, Keisuke Yamada, Naoyuki Honma, D Dahl, Keita Ohsumi, Takeo KishimotoAbstract:Using dephosphorylated neurofilament (NF) proteins as substrates, the kinase with a higher activity for in the dephosphorylated NF-H than the phosphorylated form of NF-H was searched for in the porcine Brain Extract. Most NF-H kinase activity in the Brain Extract pelleted with microtubules. The NF-H kinase purified from a high salt Extract of the microtubule pellets was composed of cdk5 and a 26 kDa protein, a fragment of the 35 kDa regulatory subunit of cdk5. In contrast to the association of the active kinase with microtubules, each of uncomplexed cdk5 and the 35 kDa regulatory subunit was differently distributed in the supernatant fraction and the pellet, respectively, by ultracentrifugation of the Brain Extract. Dephosphorylated forms of NF-H and NF-M became reactive to antibodies recoginizing in vivo phosphorylation sites (SM131, 34, and 36, JJ31 and 51) by phosphorylation with cdk5/p26. cdk5/p26 showed similar enzymatic properties to p34cdc2/cyclin B kinase; the substrate specificity and inhibition by a p34cdc2 kinase specific inhibitor, butyrolactone I. However, p34cdc2/cyclin B kinase was distinguished from cdk5/p26 by its binding to p13suc1 protein and by its reactivity to anti-p34cdc2 antibodies. In spite of similar enzymatic properties of cdk5/p26 and p34cdc2/cyclin B kinase, cdk5/26 did not display M-phase promoting activity when assayed with a cell-free system of Xenopus egg Extract. © 1995 Wiley-Liss, Inc.
Hiroshi Kataoka - One of the best experts on this subject based on the ideXlab platform.
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Dynamic regulation of prothoracic gland ecdysteroidogenesis: Manduca sexta recombinant prothoracicotropic hormone and Brain Extracts have identical effects.
Insect biochemistry and molecular biology, 2000Co-Authors: Lawrence I. Gilbert, Akira Mizoguchi, Qisheng Song, Wendy A. Smith, Shinji Nagata, R Morreale, H Matubayashi, M Shionoya, Hiroshi KataokaAbstract:Multiple assays were conducted in order to determine if the recently available recombinant prothoracicotropic hormone (rPTTH) from Manduca sexta is identical, or similar, to the natural hormone and if results from its use in a variety of assays confirm, or are inconsistent with, previous studies over the past 20years on PTTH action using Brain Extract. Brain Extracts and rPTTH showed similar, if not identical, effects on the cell biology of Manduca prothoracic gland cells with the following results: increased levels of cAMP (adenosine 3':5' cyclic monophosphate) synthesis; requirement for extracellular Ca(2+) in in vitro studies; ecdysteroidogenesis stimulation in vitro; stimulation of general and specific protein synthesis; immunocytochemical identification of the two lateral cells in each Brain hemisphere as the source of PTTH (the prothoracicotropes); the ability of antibodies to rPTTH to inhibit ecdysteroidogenesis stimulation in vitro; and the multiple phosphorylation of the ribosomal protein S6. The data revealed that Brain Extract and rPTTH show equivalent effects in all of the assays, indicating that this rPTTH is the natural PTTH of Manduca and that the data generated with Brain Extracts over the past two decades are indeed relevant.
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the Brain neurosecretory cells of the moth samia cynthia ricini immunohistochemical localization and developmental changes of the samia homologues of the bombyx prothoracicotropic hormone and bombyxin
Development Growth & Differentiation, 1995Co-Authors: Yoshimasa Yagi, Koji Nagata, Hiroshi Kataoka, Jun Ishibashi, Akira MizoguchiAbstract:We produced mouse antisera against synthetic peptides corresponding to the sequences of the Samia cynthia ricini homologues of the Bombyx mori PTTH and bombyxin. Immunohistochemical analyses of the Samia cephalic neuroendocrine system using these antisera were performed to identify the neurosecretory cells (NSC) containing the PTTH and bombyxin homologues and to examine the developmental changes in their amounts in the NSC. The results show that the PTTH and bombyxin homologues are produced by two pairs of dorsolateral and 16 pairs of dorsomedial NSC of Samia Brain, respectively, and both are transported to, and released from, the corpora allata. No clear-cut correlation was found between the fluctuation in the amount of immunoreactive substances in the Brain NSC and the endocrinologically anticipated timings of PTTH secretion. From Samia Brain Extract, two forms of PTTH activity (∼30 kDa and ∼5 kDa) were resolved through Sephadex gel filtration. The ∼30 kDa and ∼5 kDa PTTH seem to represent the PTTH and bombyxin homologues, respectively. We discuss that the ∼30 kDa PTTH homologue is the true PTTH of Samia.
Karen L Elliott - One of the best experts on this subject based on the ideXlab platform.
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evidence for a phe gly leu amide like allatostatin in the beetle tenebrio molitor
Peptides, 2010Co-Authors: Karen L Elliott, Kuen Kuen Chan, Barbara StayAbstract:The allatostatins (ASTs) with Phe-Gly-Leu-amide C-terminal sequence are multifunctional neuropeptides discovered as inhibitors of juvenile hormone (JH) synthesis by corpora allata (CA) of cockroaches. Although these ASTs inhibit JH synthesis only in cockroaches, crickets, termites and locusts, isolation of peptides or of cDNA/genomic DNA or analysis of genomes indicates their occurrence in many orders of insects with the exception of coleopterans. The gene for these ASTs has not been found in the genome of the red flour beetle Tribolium castaneum (Family Tenebrionidae). Yet, in view of widespread occurrence of these peptides in insects, crustaceans and nematodes, they would be expected to occur in beetles. This study provides evidence for the presence of FGLa-like ASTs in the tenebrionid beetle, Tenebrio molitor, and scarabid beetle, Popillia japonica. Extract of Brain from both beetles inhibited JH synthesis by cockroach CA dose dependently and reversibly. 20 Brain equivalents of T. molitor and P. japonica Extracts inhibited JH synthesis 64 ± 5 and 65 ± 0.6% respectively. Antibody against cockroach allatostatin (Diploptera punctata AST-7) used in an enzyme-linked immunosorbent assay reacted with Brain Extract of these beetles. Antibody against D. punctata AST-5 localized FGLa-like ASTs in the Brain and subesophageal ganglion of T. molitor and P. japonica. In addition, pretreatment of T. molitor Brain Extract with anti-D. punctata AST-5 reduced the inhibition of JH synthesis and pretreatment of anti-D. punctata AST-5 with D. punctata AST-5 diminished the immunoreactivity of the antibody. Thus we predict that FGLa-like allatostatins will be found in beetles.
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identification of phe gly leu amide type allatostatin 7 in reticulitermes flavipes its localization in tissues and relation to juvenile hormone synthesis
Peptides, 2009Co-Authors: Karen L Elliott, Lynn M Teesch, Kuen Kuen Chan, Omar Clor, Barbara StayAbstract:Abstract The allatostatins (ASTs), with a Tyr/Phe-Xaa-Phe-Gly-Leu/Ile-amide C-terminus, are neuropeptides that occur in many orders of insects, but are known to inhibit juvenile hormone (JH) synthesis by corpora allata (CA) only in cockroaches, crickets, and termites. 5 AST peptides with similar sequences to those of 6 species of cockroaches have been isolated and sequenced from Extract of Brain tissue of the termite Reticulitermes flavipes. The amino acid sequence of a 6th peptide, R. flavipes AST-7, determined by LC–MS/MS following HPLC fractionation of Brain Extract, is S-P-S-S-G-N-Q-R-L-Y-G-F-G-L-NH2. The 8 terminal amino acids are identical to AST-7 of the cockroach Diploptera punctata. R. flavipes and D. punctata AST-7s inhibited JH synthesis by CA of both species equally and their affinity for antibody against D. punctata AST-7 is similar. Immunoreactivity of termite tissue with this antibody indicates neuro- and myomodulatory activity of the peptide in addition to its demonstrated allatostatic function. The density of AST immunostaining in axons within the CA of R. flavipes and the rate of JH synthesis by similar glands were negatively correlated. This is evidence that when AST is abundant in the glands it is being released in vivo to limit JH production.
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isolation of cockroach phe gly leu amide allatostatins from the termite reticulitermes flavipes and their effect on juvenile hormone synthesis
Journal of Insect Physiology, 2008Co-Authors: Koichiro J Yagi, Stephen S Tobe, Karen L Elliott, Lynn M Teesch, Barbara StayAbstract:Immunoreactivity to cockroach Diploptera punctata allatostatin-7 (Dippu AST-7) has been demonstrated previously in axons innervating the corpora allata of the termite Reticulitermes flavipes. This peptide and Dippu AST-11 inhibited juvenile hormone (JH) synthesis by corpora allata (CA) of brachypterous neotenic reproductives (secondary reproductives) of termites. The present study shows that R. flavipes CA are also inhibited by Dippu AST-2, AST-5, AST-8, and AST-9 at approximately the same rank order of potency as demonstrated in D. punctata. Another allatostatin from Periplaneta americana (Peram AST-12) also inhibits JH synthesis by R. flavipes CA. Sensitivity to the allatostatins is higher in glands with low rates of JH synthesis than in those with relatively high JH synthetic rates as has been demonstrated in CA from male and female secondary reproductives as well as in those from non-egg-laying and egg-laying females. The identical inhibitory effects of R. flavipes Brain Extract on CA from both D. punctata and R. flavipes and the isolation and identification of five cockroach allatostatins (Dippu AST-1, AST-2, AST-5, AST-8, and Peram AST-12) from termite Brain Extract reflect the close relationship between cockroaches and termites.
Akira Mizoguchi - One of the best experts on this subject based on the ideXlab platform.
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Dynamic regulation of prothoracic gland ecdysteroidogenesis: Manduca sexta recombinant prothoracicotropic hormone and Brain Extracts have identical effects.
Insect biochemistry and molecular biology, 2000Co-Authors: Lawrence I. Gilbert, Akira Mizoguchi, Qisheng Song, Wendy A. Smith, Shinji Nagata, R Morreale, H Matubayashi, M Shionoya, Hiroshi KataokaAbstract:Multiple assays were conducted in order to determine if the recently available recombinant prothoracicotropic hormone (rPTTH) from Manduca sexta is identical, or similar, to the natural hormone and if results from its use in a variety of assays confirm, or are inconsistent with, previous studies over the past 20years on PTTH action using Brain Extract. Brain Extracts and rPTTH showed similar, if not identical, effects on the cell biology of Manduca prothoracic gland cells with the following results: increased levels of cAMP (adenosine 3':5' cyclic monophosphate) synthesis; requirement for extracellular Ca(2+) in in vitro studies; ecdysteroidogenesis stimulation in vitro; stimulation of general and specific protein synthesis; immunocytochemical identification of the two lateral cells in each Brain hemisphere as the source of PTTH (the prothoracicotropes); the ability of antibodies to rPTTH to inhibit ecdysteroidogenesis stimulation in vitro; and the multiple phosphorylation of the ribosomal protein S6. The data revealed that Brain Extract and rPTTH show equivalent effects in all of the assays, indicating that this rPTTH is the natural PTTH of Manduca and that the data generated with Brain Extracts over the past two decades are indeed relevant.
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the Brain neurosecretory cells of the moth samia cynthia ricini immunohistochemical localization and developmental changes of the samia homologues of the bombyx prothoracicotropic hormone and bombyxin
Development Growth & Differentiation, 1995Co-Authors: Yoshimasa Yagi, Koji Nagata, Hiroshi Kataoka, Jun Ishibashi, Akira MizoguchiAbstract:We produced mouse antisera against synthetic peptides corresponding to the sequences of the Samia cynthia ricini homologues of the Bombyx mori PTTH and bombyxin. Immunohistochemical analyses of the Samia cephalic neuroendocrine system using these antisera were performed to identify the neurosecretory cells (NSC) containing the PTTH and bombyxin homologues and to examine the developmental changes in their amounts in the NSC. The results show that the PTTH and bombyxin homologues are produced by two pairs of dorsolateral and 16 pairs of dorsomedial NSC of Samia Brain, respectively, and both are transported to, and released from, the corpora allata. No clear-cut correlation was found between the fluctuation in the amount of immunoreactive substances in the Brain NSC and the endocrinologically anticipated timings of PTTH secretion. From Samia Brain Extract, two forms of PTTH activity (∼30 kDa and ∼5 kDa) were resolved through Sephadex gel filtration. The ∼30 kDa and ∼5 kDa PTTH seem to represent the PTTH and bombyxin homologues, respectively. We discuss that the ∼30 kDa PTTH homologue is the true PTTH of Samia.