Regulation of the type-II gonadotrophin α and β subunit mRNAs by œstradiol and testosterone in the European eel

Quérat, Bruno; Hardy, A.; Fontaine, Y.A.

doi:10.1677/jme.0.0070081

Cited by 77 publications

(33 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Both steroids increased pituitary LH content and steady state levels of LH subunit mRNA. These results are consistent with results of studies in other salmonids which have shown that E2 or aromatizable androgens increase pituitary LH (maturational GTH) in intact juvenile trout (Crim & Peter 1978, Crim & Evans 1979, Gielen & Goos 1983, Magri et al 1985 and LH transcripts in trout and eel (Trinh et al 1986, Querat et al 1991a. The effects of E2 are likely through increases in transcription as has been found in rats (Shupnik et al 1989, Shupnik & Rosenzweig 1991 since the upstream regulatory region of the salmon LH gene contains functional estrogen response elements (Xiong et al 1994b).…”

Section: Discussionsupporting

confidence: 90%

“…However, due to the relatively recent discovery of FSH in salmon, very little is known about the mechanisms for regulation of FSH synthesis and secretion. Numerous studies in teleosts have demonstrated that aromatizable androgens and estradiol-17 (E2) increase pituitary levels of immunoreactive LH (Crim & Evans 1979, Crim et al 1981, Gielen et al 1982, Dufour et al 1983, Borg et al 1985, Magri et al 1985, Schreibman et al 1986) and increase levels of LH subunit mRNA (Trinh et al 1986, Querat et al 1991a. Recent studies (Xiong et al 1994a,b,c) have shown that the promoter for the LH subunit contains estrogen response elements.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of sex steroids on gonadotropin (FSH and LH) regulation in coho salmon (Oncorhynchus kisutch)

Dickey

Swanson²

1998

Journal of Molecular Endocrinology

135

View full text Add to dashboard Cite

The effect of steroid hormone treatment on coho salmon (Oncorhynchus kisutch) was examined. The cDNAs for coho salmon FSH and LH subunits were cloned and sequenced using reverse transcriptase PCR. Northern blot analysis revealed that a single transcript of 1 kb for each of these subunits was present in the pituitaries of vitellogenic and spermiating coho salmon. RNase protection assays (RPAs) were developed to quantify FSH and LH subunit transcript levels. For the RPAs, antisense RNA probes and sense RNA standards were prepared from a region of the cDNAs which spanned the signal peptide and a portion of the mature protein. These RPAs were used to examine the effects of exogenous steroids including testosterone, estradiol-17 (E2) and 17 ,20 -dihydroxy-4-pregnen-3-one (17 ,20 -P) in vivo, in coho salmon at three time points during the spring period of gonadal growth when plasma levels of FSH are increasing. Both testosterone and E2 increased steady state mRNA levels of LH , whereas E2 decreased steady state mRNA levels of FSH in one experiment. Thus, the RPAs were able to detect changes in steady state mRNA levels in response to exogenous steroid treatment. Plasma and pituitary levels of FSH and LH were also measured using RIA. Throughout the experimental series, FSH plasma levels decreased in response to exogenous testosterone and E2 administration, while 17 , 20 -P had no effect on FSH plasma levels. Plasma LH levels were not detected throughout the course of the experiment. Pituitary LH increased in response to testosterone and E2, while pituitary FSH levels did not change. 17 ,20 -P had no effect on pituitary FSH or LH content during the experiment. Thus, regulation of the gonadotropins in coho salmon occurs at both the transcriptional as well as the translational level. Testosterone and E2 appear to have negative feedback effects on FSH, but positive feedback on LH.

show abstract

Section: Discussionsupporting

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Effects of sex steroids on gonadotropin (FSH and LH) regulation in coho salmon (Oncorhynchus kisutch)

Dickey

Swanson²

1998

Journal of Molecular Endocrinology

135

View full text Add to dashboard Cite

show abstract

“…It has been suggested that estrogens and androgens stimulate GtH-II synthesis in the pituitary (Querat et al 1991, Huggard et al 1996, Nagae et al 1996. Dickey & Swanson (1995) found that in immature coho salmon injected with estradiol there was an increase in the steadystate mRNA levels of GtH-II but not GtH-I.…”

Section: Discussionmentioning

confidence: 99%

“…The use of a molecular biological approach has made it possible to examine changes in the levels of the mRNA of the gonadotropins during the gonadal cycle. Changes in the expression of GtHs during the gonadal cycle, or under the influence of different hormones, have been studied in recent years in teleosts (Querat et al 1991, Weil et al 1995, Elizur et al 1996, Nagae et al 1996, Liu et al 1997.…”

Section: Introductionmentioning

confidence: 99%

Blue gourami (Trichogaster trichopterus) gonadotropic beta subunits (I and II) cDNA sequences and expression during oogenesis

Jackson

Goldberg²,

Ofir³

et al. 1999

Journal of Molecular Endocrinology

View full text Add to dashboard Cite

We have cloned two cDNAs from the pituitary gland of blue gourami (Trichogaster trichopterus), coding for the subunits of the gonadotropin hormones GtH-I and GtH-II. The two cDNAs were sequenced and subjected to sequence analysis. We have found that the deduced amino acid sequences of both cDNAs were most similar to their striped bass counterparts. The GtH-I subunits of blue gourami and striped bass shared 73% of their residues, and the GtH-II subunits 84%. The cloning of the cDNAs ofGtH-I and GtH-II has enabled us to measure the expression of their respective mRNAs in the pituitaries of female blue gourami at different stages of the reproductive cycle. The highest levels of GtH-I and GtH-II mRNA were found in specimens classified as high vitellogenic and in females that were at the final stages of oocyte maturation.

show abstract

“…RNA from pooled CNS, individual ganglia, and peripheral tissues were isolated using the lithium chloride method previously described (Querat et al, 1991). RNA samples were quantified based on absorbance at 260 nm.…”

Section: Rna Isolationmentioning

confidence: 99%

Molecular cloning, expression pattern, and immunocytochemical localization of a gonadotropin-releasing hormone-like molecule in the gastropod mollusk, Aplysia californica

Zhang

Tello

Zhang

et al. 2008

General and Comparative Endocrinology

105

View full text Add to dashboard Cite

Successful reproduction in vertebrates depends upon the actions of gonadotropin-releasing hormone (GnRH). Despite the wide presence of GnRH in Phylum Chordata, GnRH has not been isolated in protostomes other than the common octopus. To provide information on the evolution of this critical hormone, we isolated the full-length cDNA of a GnRH-like molecule from the central nervous system of a gastropod mollusk, the sea hare Aplysia californica. The open reading frame of this cDNA encodes a protein of 147 amino acids. The molecular architecture of the deduced protein is highly homologous to that reported for the prepro-octopus GnRH (oct-GnRH) and consists of a putative signal peptide, a GnRH dodecapeptide, a downstream processing site, and a GnRH-associated peptide (GAP). The deduced amino acid sequence of the Aplysia GnRH (ap-GnRH) is QNYHFSNGWYAG and differs from oct-GnRH by only two amino acids. The transcript for ap-GnRH is widely expressed in the central nervous system (CNS), the ovotestis, and the atrial gland, an exocrine gland. Immunocytochemistry (ICC) using an antiserum against oct-GnRH detected immunoreactive neurons in all CNS ganglia examined, and the staining was abolished by the preadsorption of the antiserum with synthetic ap-GnRH. In sum, ap-GnRH sequence is the first gastropod GnRH-like molecule to be elucidated. Further, it represents one of the only two GnRH-like molecules found outside Phylum Chordata. These data refute the possibility that oct-GnRH arose singly in cephalopods by convergent evolution and provide valuable support for an ancient origin of GnRH during metazoan evolution.

show abstract

Regulation of the type-II gonadotrophin α and β subunit mRNAs by œstradiol and testosterone in the European eel

Cited by 77 publications

References 0 publications

Effects of sex steroids on gonadotropin (FSH and LH) regulation in coho salmon (Oncorhynchus kisutch)

Effects of sex steroids on gonadotropin (FSH and LH) regulation in coho salmon (Oncorhynchus kisutch)

Blue gourami (Trichogaster trichopterus) gonadotropic beta subunits (I and II) cDNA sequences and expression during oogenesis

Molecular cloning, expression pattern, and immunocytochemical localization of a gonadotropin-releasing hormone-like molecule in the gastropod mollusk, Aplysia californica

Contact Info

Product

Resources

About