The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Morten Møller - One of the best experts on this subject based on the ideXlab platform.
-
Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland
BioMed Research International, 2014Co-Authors: Kristian Rohde, Morten Møller, Martin F. RathAbstract:Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod Homeobox (CRX) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that Homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.
-
Homeobox Genes in the Rodent Pineal Gland: Roles in Development and Phenotype Maintenance
Neurochemical Research, 2013Co-Authors: Martin F. Rath, Kristian Rohde, David C. Klein, Morten MøllerAbstract:The pineal gland is a neuroendocrine gland responsible for nocturnal synthesis of melatonin. During early development of the rodent pineal gland from the roof of the diencephalon, Homeobox genes of the orthodenticle Homeobox (Otx)- and paired box (Pax)-families are expressed and are essential for normal pineal development consistent with the well-established role that Homeobox genes play in developmental processes. However, the pineal gland appears to be unusual because strong Homeobox gene expression persists in the pineal gland of the adult brain. Accordingly, in addition to developmental functions, Homeobox genes appear to be key regulators in postnatal phenotype maintenance in this tissue. In this paper, we review ontogenetic and phylogenetic aspects of pineal development and recent progress in understanding the involvement of homebox genes in rodent pineal development and adult function. A working model is proposed for understanding the sequential action of Homeobox genes in controlling development and mature circadian function of the mammalian pinealocyte based on knowledge from detailed developmental and daily gene expression analyses in rats, the pineal phenotypes of homebox gene-deficient mice and studies on development of the retinal photoreceptor; the pinealocyte and retinal photoreceptor share features not seen in other tissues and are likely to have evolved from the same ancestral photodetector cell.
Martin F. Rath - One of the best experts on this subject based on the ideXlab platform.
-
Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland
BioMed Research International, 2014Co-Authors: Kristian Rohde, Morten Møller, Martin F. RathAbstract:Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod Homeobox (CRX) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that Homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.
-
Homeobox Genes in the Rodent Pineal Gland: Roles in Development and Phenotype Maintenance
Neurochemical Research, 2013Co-Authors: Martin F. Rath, Kristian Rohde, David C. Klein, Morten MøllerAbstract:The pineal gland is a neuroendocrine gland responsible for nocturnal synthesis of melatonin. During early development of the rodent pineal gland from the roof of the diencephalon, Homeobox genes of the orthodenticle Homeobox (Otx)- and paired box (Pax)-families are expressed and are essential for normal pineal development consistent with the well-established role that Homeobox genes play in developmental processes. However, the pineal gland appears to be unusual because strong Homeobox gene expression persists in the pineal gland of the adult brain. Accordingly, in addition to developmental functions, Homeobox genes appear to be key regulators in postnatal phenotype maintenance in this tissue. In this paper, we review ontogenetic and phylogenetic aspects of pineal development and recent progress in understanding the involvement of homebox genes in rodent pineal development and adult function. A working model is proposed for understanding the sequential action of Homeobox genes in controlling development and mature circadian function of the mammalian pinealocyte based on knowledge from detailed developmental and daily gene expression analyses in rats, the pineal phenotypes of homebox gene-deficient mice and studies on development of the retinal photoreceptor; the pinealocyte and retinal photoreceptor share features not seen in other tissues and are likely to have evolved from the same ancestral photodetector cell.
Krishanu Mukherjee - One of the best experts on this subject based on the ideXlab platform.
-
eLS - Evolution of Plant Homeobox Genes
Encyclopedia of Life Sciences, 2010Co-Authors: Krishanu Mukherjee, Luciano BrocchieriAbstract:Plant Homeobox genes can be classified into 14 evolutionary classes, each characterised by fusion of the homeodomain with class-specific codomains. Among these classes only BEL and KNOX are found in red algae, whereas unicellular green algae also include members of the classes WOX, DDT and PINTOX. All 14 classes are found only in land plants, including moss and vascular plants, suggesting that Homeobox genes have proliferated within each class particularly in flowering plants, indicating that all classes had already differentiated in the common ancestor of moss and vascular plants. In different land plants, including moss and flowering plant, multiple gene copies are observed for most classes, suggesting that proliferation and functional differentiation of gene paralogues within the original classes reflects the increasing complexity of plant development and architecture. Key Concepts: Homeobox genes in plant can be classified into 14 distinct classes all of which had appeared in the common ancestor of Bryophyta and Tracheophyta. Functional differentiation of plant homeodomain protein classes relates to acquisition of a class-specific codomain architecture. Proliferation of paralogous genes within each class in land plants concomitantly with increasing organismal complexity. Keywords: Homeobox; homeodomain; transcription factor; plant
-
a comprehensive classification and evolutionary analysis of plant Homeobox genes
Molecular Biology and Evolution, 2009Co-Authors: Thomas R. Bürglin, Krishanu Mukherjee, Luciano BrocchieriAbstract:The full complement of Homeobox transcription factor sequences, including genes and pseudogenes, was determined from the analysis of 10 complete genomes from flowering plants, moss, Selaginella, unicellular green algae, and red algae. Our exhaustive genome-wide searches resulted in the discovery in each class of a greater number of Homeobox genes than previously reported. All Homeobox genes can be unambiguously classified by sequence evolutionary analysis into 14 distinct classes also characterized by conserved intron–exon structure and by unique codomain architectures. We identified many new genes belonging to previously defined classes (HD-ZIP I to IV, BEL, KNOX, PLINC, WOX). Other newly identified genes allowed us to characterize PHD, DDT, NDX, and LD genes as members of four new evolutionary classes and to define two additional classes, which we named SAWADEE and PINTOX. Our comprehensive analysis allowed us to identify several newly characterized conserved motifs, including novel zinc finger motifs in SAWADEE and DDT. Members of the BEL and KNOX classes were found in Chlorobionta (green plants) and in Rhodophyta. We found representatives of the DDT, WOX, and PINTOX classes only in green plants, including unicellular green algae, moss, and vascular plants. All 14 Homeobox gene classes were represented in flowering plants, Selaginella, and moss, suggesting that they had already differentiated in the last common ancestor of moss and vascular plants.
Kristian Rohde - One of the best experts on this subject based on the ideXlab platform.
-
Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland
BioMed Research International, 2014Co-Authors: Kristian Rohde, Morten Møller, Martin F. RathAbstract:Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod Homeobox (CRX) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that Homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.
-
Homeobox Genes in the Rodent Pineal Gland: Roles in Development and Phenotype Maintenance
Neurochemical Research, 2013Co-Authors: Martin F. Rath, Kristian Rohde, David C. Klein, Morten MøllerAbstract:The pineal gland is a neuroendocrine gland responsible for nocturnal synthesis of melatonin. During early development of the rodent pineal gland from the roof of the diencephalon, Homeobox genes of the orthodenticle Homeobox (Otx)- and paired box (Pax)-families are expressed and are essential for normal pineal development consistent with the well-established role that Homeobox genes play in developmental processes. However, the pineal gland appears to be unusual because strong Homeobox gene expression persists in the pineal gland of the adult brain. Accordingly, in addition to developmental functions, Homeobox genes appear to be key regulators in postnatal phenotype maintenance in this tissue. In this paper, we review ontogenetic and phylogenetic aspects of pineal development and recent progress in understanding the involvement of homebox genes in rodent pineal development and adult function. A working model is proposed for understanding the sequential action of Homeobox genes in controlling development and mature circadian function of the mammalian pinealocyte based on knowledge from detailed developmental and daily gene expression analyses in rats, the pineal phenotypes of homebox gene-deficient mice and studies on development of the retinal photoreceptor; the pinealocyte and retinal photoreceptor share features not seen in other tissues and are likely to have evolved from the same ancestral photodetector cell.
Yoshinobu Eishi - One of the best experts on this subject based on the ideXlab platform.
-
Homeobox transcriptional factor engrailed Homeobox 1 is expressed specifically in normal and neoplastic sweat gland cells
Histopathology, 2018Co-Authors: Keiko Miura, Shinya Ayabe, Kou Kayamori, Takeshi Namiki, Noboru Ando, Takumi Akashi, Yoshinobu EishiAbstract:A number of Homeobox transcriptional factors are utilised as organ-specific markers in the histopathological diagnosis of neoplasms. We have screened a Homeobox gene that is expressed specifically in normal sweat gland cells and is useful for the histopathological diagnosis of sweat gland neoplasms. By screening an open database resource of The Human Protein Atlas, 37 genes among the 235 Homeobox transcriptional factors were found to be expressed specifically in the skin. Among those 37 genes, the engrailed Homeobox 1 (En1) was expressed in normal eccrine glands but not in the epidermal keratinocytes. Expression of En1 was found throughout the eccrine glands, but not in the apocrine secretory coils, sebaceous glands or hair follicles. Expression of En1 was examined immunohistochemically in 111 cases of cutaneous epithelial neoplasms. All nine cases of poroma, seven cases of spiradenoma and six cases of syringoma, which are considered to differentiate towards eccrine glands, showed positive nuclear staining in most of the tumour cells. Sebaceous gland and hair follicle tumours were immunonegative. En1 was expressed focally in the epidermal neoplasms of seborrheic keratosis and squamous cell carcinoma. Engrailed Homeobox 1 was expressed specifically in normal eccrine glands and was expressed in most of the tumour cells of sweat gland neoplasms with eccrine gland differentiation. En1 was expressed focally in epidermal neoplasms; however, it was absent in sebaceous or hair follicle neoplasms. These findings will help in the histopathological diagnosis as well as understanding of the histogenesis of sweat gland neoplasms. © 2018 John Wiley & Sons Ltd.
-
Homeobox transcriptional factor engrailed Homeobox 1 is expressed specifically in normal and neoplastic sweat gland cells.
Histopathology, 2018Co-Authors: Keiko Miura, Shinya Ayabe, Kou Kayamori, Takeshi Namiki, Noboru Ando, Takumi Akashi, Yoshinobu EishiAbstract:AIMS: A number of Homeobox transcriptional factors are utilised as organ-specific markers in the histopathological diagnosis of neoplasms. We have screened a Homeobox gene that is expressed specifically in normal sweat gland cells and is useful for the histopathological diagnosis of sweat gland neoplasms. METHODS AND RESULTS: By screening an open database resource of The Human Protein Atlas, 37 genes among the 235 Homeobox transcriptional factors were found to be expressed specifically in the skin. Among those 37 genes, the engrailed Homeobox 1 (En1) was expressed in normal eccrine glands but not in the epidermal keratinocytes. Expression of En1 was found throughout the eccrine glands, but not in the apocrine secretory coils, sebaceous glands or hair follicles. Expression of En1 was examined immunohistochemically in 111 cases of cutaneous epithelial neoplasms. All nine cases of poroma, seven cases of spiradenoma and six cases of syringoma, which are considered to differentiate towards eccrine glands, showed positive nuclear staining in most of the tumour cells. Sebaceous gland and hair follicle tumours were immunonegative. En1 was expressed focally in the epidermal neoplasms of seborrheic keratosis and squamous cell carcinoma. CONCLUSION: Engrailed Homeobox 1 was expressed specifically in normal eccrine glands and was expressed in most of the tumour cells of sweat gland neoplasms with eccrine gland differentiation. En1 was expressed focally in epidermal neoplasms; however, it was absent in sebaceous or hair follicle neoplasms. These findings will help in the histopathological diagnosis as well as understanding of the histogenesis of sweat gland neoplasms.
