| Origin of germ cells, sex determination, and sex inversion in medusae of the genus Clytia (Hydrozoa, leptomedusae): the influence of temperature. | |
| | |
MedLine Citation:
|
PMID: 10900443 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
In Cnidaria, a separation between soma and germline remains unclear. In this work, we studied the origin of germinal cells and determination of the sexual phenotype in Clytia hemisphaerica and Clytia sp. Colonies of C. Hemisphaerica were cultivated and the medusae liberated by each colony raised until maturity. Two hermaphrodite colonies were obtained, liberating male and female medusae. These two colonies and their medusae were raised at 15 degrees C, 21 degrees C, or 24 degrees C. The medusae budded and cultured at 24 degrees C were mainly female (80%). In contrast, if the medusae were released at 15 degrees C, at whatever temperature they were raised later, they were mainly male (85%). The same occurred if, after release at 24 degrees C but before the formation of the gametes, they were kept at 15 degrees C for at least 24 hr. We suggest that there are two subpopulations of germ cells. The female line will be dominant at 24 degrees C but temperature sensitive, with inhibition of this line by a temperature drop to 15 degrees C, this inverting the population sex-ratio. The irreversible action of a temperature drop to 15 degrees C supports the view that the germ cells are isolated very early. In C. hemisphaerica, hermaphrodite medusae were never observed. On the contrary, in Clytia sp., probably a new species, we have found male, female, but also hermaphrodite specimens. This is the second definite example of hermaphroditism described in any hydromedusan. The transformation of female into hermaphrodite then into male specimens occurs at 13 degrees C. These results demonstrate the unstable character of genetic sex determination in cnidarians, at least in certain species. |
| | |
Authors:
|
D Carré; C Carré |
Related Documents
:
|
7631433 - Refractoriness of the immature rat epididymis to the early cadmium lesion. 2664543 - Bombesin produces hypothermia in insulin treated rats. 16942763 - Protective roles of hydroxyethyl starch 130/0.4 in intestinal inflammatory response and... |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: The Journal of experimental zoology Volume: 287 ISSN: 0022-104X ISO Abbreviation: J. Exp. Zool. Publication Date: 2000 Aug |
Date Detail:
|
Created Date: 2000-08-10 Completed Date: 2000-08-10 Revised Date: 2003-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 0375365 Medline TA: J Exp Zool Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 233-42 Citation Subset: IM |
Affiliation:
|
UMR 7009, CNRS, Observatoire Océanologique, F-06234, Villefranche-sur-Mer, France. carre@olos-vlfr.fr |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Female Germ Cells / cytology, physiology* Gonads / cytology Hermaphroditism Hydra / physiology* Male Sex Determination (Genetics)* Sex Ratio Sex Reversal, Gonadal* Temperature |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Evidence of temperature-dependent sex determination in the European sea bass (Dicentrarchus labrax L...
Next Document: Multiple triggers of oocyte maturation in nemertean worms: the roles of calcium and serotonin.