3 Expression of the Vasotocin and Isotocin Gene Family in Fish

Urano, Akihisa; Kubokawa, Kaoru; Hiraoka, Shûichi

doi:10.1016/s1546-5098(08)60064-3

Cited by 26 publications

(15 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This may include neurohormones (e.g. dopamine, thyrotropin-releasing hormone, gonadotropin-releasing hormone, isotocin and vasotocin) released from cells in the vicinity of the transplanted RPD (Nagahama et al 1975, Wigham & Ball 1977, Wigham et al 1977, Urano et al 1994, Weber et al 1997 or osmosensitive changes in circulating levels (e.g. steroids) or brain levels of other hormones as well (e.g.…”

Section: Discussionmentioning

confidence: 99%

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Shepherd¹,

Sakamoto

Hyodo³

et al. 1999

Journal of Endocrinology

View full text Add to dashboard Cite

We examined the effects of environmental salinity on circulating levels of the two prolactins (tPRL 177 and tPRL 188 ) and levels of pituitary tPRL 177 and tPRL 188 mRNA in the euryhaline tilapia, Oreochromis mossambicus. Fish were sham-operated or hypophysectomized and the rostral pars distalis (RPD) autotransplanted onto the optic nerve. Following post-operative recovery in ¼ seawater, tilapia were transferred to fresh water (FW), ¼ seawater (SW) or SW. Serum tPRL 177 and tPRL 188 levels in sham-operated and RPD-autotransplanted fish were highest in FW and decreased as salinity was increased. tPRL 177 and tPRL 188 mRNA levels in RPD implants as well as in pituitaries from the sham-operated fish were also highest in FW and decreased with increasing salinity. Serum osmolality increased with salinity, with the highest levels occurring in the seawater groups. We conclude that some plasma factor (probably plasma osmolality), in the absence of hypothalamic innervation, exerts a direct regulatory action on prolactin release and gene expression in the pituitary of O. mossambicus. This regulation is in accord with the actions of the two prolactins in the freshwater osmoregulation of the tilapia.

show abstract

Section: Discussionmentioning

confidence: 99%

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Shepherd¹,

Sakamoto

Hyodo³

et al. 1999

Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…Analysis of the precursor molecules, which are much larger than the nonapeptides, gives more precise and reliable information for estimating the molecular evolutionary relationships than does analysis based on substitutions only in the nine amino acid residues. Using statistical comparison of gene structures and the predicted amino acid sequences of precursors, Urano and colleagues (3)(4)(5) have proposed that teleost neurohypophysial hormone genes have their own evolutionary history separate from that of the tetrapod genes. Their hypothesis is further supported by the structural characteristics of neurohypophysial hormone precursors, including composition and the presence or absence of posttranslational modification sites (2)(3)(4)(5).…”

mentioning

confidence: 99%

Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe ² ]mesotocin precursors homologous to tetrapod-type precursors

Hyodo

Ishii

Joss³

1997

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

In view of the well-established role of neurohypophysial hormones in osmoregulation of terrestrial vertebrates, lungfishes are a key group for study of the molecular and functional evolution of the hypothalamo-neurohypophysial system. Here we report on the primary structure of the precursors encoding vasotocin (VT) and [ Moreover, molecular phylogenetic analysis shows that neurohypophysial hormone genes of the lungfish are closely related to those of the toad. The present results along with previous morphological findings indicate that the hypothalamoneurohypophysial system of the lungfish has evolved along the tetrapod lineage, whereas the teleosts form a separate lineage, both within the class Osteichthyes.Neurohypophysial hormones are nonapeptides regulating various physiological events related especially to water and salt metabolism and reproduction. Twelve distinct nonapeptide principles have been chemically characterized in a wide variety of vertebrates, and are classified into two groups: the vasopressin (VP) and the oxytocin (OT) families. They are believed to have developed from a common ancestral molecule by gene duplication (1). All vertebrate species, except for the cyclostomes, contain at least one VP family peptide and one OT family peptide. Several schemes have been proposed as pathways of hormonal molecular evolution based on amino acid sequences of nonapeptides and their phyletic distribution (1).Complementary DNA and genomic analyses have shown that neurohypophysial nonapeptides are synthesized as large precursor molecules (2). Analysis of the precursor molecules, which are much larger than the nonapeptides, gives more precise and reliable information for estimating the molecular evolutionary relationships than does analysis based on substitutions only in the nine amino acid residues. Using statistical comparison of gene structures and the predicted amino acid sequences of precursors, Urano and colleagues (3-5) have proposed that teleost neurohypophysial hormone genes have their own evolutionary history separate from that of the tetrapod genes. Their hypothesis is further supported by the structural characteristics of neurohypophysial hormone precursors, including composition and the presence or absence of posttranslational modification sites (2-5).Lungfishes are the closest surviving freshwater relatives of the Devonian fish group from which early amphibians are assumed to have evolved. Acher and his colleagues (6, 7) reported that lungfishes have mesotocin (MT), the nonmammalian tetrapod type hormone, as their OT family hormone, whereas all teleosts examined have isotocin (IT). They have proposed an evolutionary lineage of IT (teleosts)-MT (non-mammalian tetrapods)-OT (mammals) and suggest a close relationship between lungfishes and amphibians. However, the data on amino acid substitutions in nonapeptides are insufficient to estimate the molecular phylogeny of the whole neurohypophysial hormone genes. For their VP family peptide, lungfishes have vasotocin (VT), which is common to all ...

show abstract

“…Also the preprosomatostatin sequence was used to confirm the close relationship of the lungfish and tetrapods (Trabucchi et al, 1999). Several studies have reported the usefulness of some polypeptide hormone precursors (Rubin and Dores, 1994;Urano et al, 1994;Grober et al, 1995;Rubin and Dores, 1995) in phylogenetic analysis, where the spacer region was often the informative character. Comparison of the deduced amino acid sequences of the preproinsulins of the present study to those from other fish and vertebrate species using maximum parsimony, revealed a grouping of the osteoglossomorphs, suggesting a monophyletic origin (same clade).…”

Section: Phylogenetic Analysismentioning

confidence: 99%

Molecular cloning of preproinsulin cDNAs from several osteoglossomorphs and a cyprinid

Al‐Mahrouki

Irwin

Graham

et al. 2001

Molecular and Cellular Endocrinology

View full text Add to dashboard Cite

Several preproinsulin cDNAs were isolated and characterized from four members of the Osteoglossomorpha (an ancient teleost group); Osteoglossum bicirrhosum (arawana), Pantodon buchholzi (butterfly fish), Notopterus chitala (feather fin knife fish), Hiodon alosoides (goldeye) and Gnathonemus petersii (elephantnose). In addition, we isolated and characterized the preproinsulin cDNA from Catostomus commersoni (white sucker, as a representative of a generalized teleost). The comparative analysis of the sequences revealed conservation of the cystine residues known to be involved in the formation of the disulfide bridges, as well as residues involved in the hexamer formation, except for B-17 in the butterfly fish, the arawana and the goldeye. However, the N-terminus of the B-chain was very weakly conserved among the species studied. Residues known to be significant for maintaining receptor-binding conformation and those known to comprise the receptor-binding domain were all conserved, except for a conservative substitution at B13, aspartate substituted glutamate in the arawana, goldeye, butterfly fish and white sucker, and at B16, phenylalanine substituted tyrosine in the elephantnose. Phylogenetic analysis of the sequences revealed a monophyletic grouping of the osteoglossomorphs, and showed that they were not the most basal living teleost. Comparative sequence analysis of preproinsulins among the osteoglossomorphs was useful in assessment of intergroup relationship, relating elephantnose with the feather fin knife fish and the arawana, butterfly fish, and goldeye. This arrangement of species is consistent with relationships based on other more classical parameters, except for the goldeye which was assessed as being sister to all the osteoglossomorphs. The white sucker was grouped with the common carp and both are cyprinids.

show abstract

3 Expression of the Vasotocin and Isotocin Gene Family in Fish

Cited by 26 publications

References 46 publications

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe ² ]mesotocin precursors homologous to tetrapod-type precursors

Molecular cloning of preproinsulin cDNAs from several osteoglossomorphs and a cyprinid

Contact Info

Product

Resources

About

3 Expression of the Vasotocin and Isotocin Gene Family in Fish

Cited by 26 publications

References 46 publications

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Is the primitive regulation of pituitary prolactin (tPRL177 and tPRL188) secretion and gene expression in the euryhaline tilapia (Oreochromis mossambicus) hypothalamic or environmental?

Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe 2 ]mesotocin precursors homologous to tetrapod-type precursors

Molecular cloning of preproinsulin cDNAs from several osteoglossomorphs and a cyprinid

Contact Info

Product

Resources

About

Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe ² ]mesotocin precursors homologous to tetrapod-type precursors