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  • A case of hermaphroditism in the gonochoristic sea urchin, Strongylocentrotus purpuratus , reveals key mechanisms of sex determination
Title: A case of hermaphroditism in the gonochoristic sea urchin, Strongylocentrotus purpuratus , reveals key mechanisms of sex determination
Abstract Sea urchins are usually gonochoristic, with all of their five gonads either testes or ovaries. Here, we report an unusual case of hermaphroditism in the purple sea urchin, Strongylocentrotus purpuratus. The hermaphrodite is self-fertile, and one of the gonads is an ovotestis; it is largely an ovary with a small segment containing fully mature sperm. Molecular analysis demonstrated that each gonad producedviable gametes, and we identified for the first time a somatic sex-specific marker in this phylum: Doublesex and mab-3 related transcription factor 1 (DMRT1). This finding also enabled us to analyze the somatic tissues of the hermaphrodite, and we found that the oral tissues (including gut) were out of register with the aboral tissues (including tube feet) enabling a genetic lineage analysis. Results from this study support a genetic basis of sex determination in sea urchins, the viability of hermaphroditism, and distinguish gonad determination from somatic tissue organization in the adult.  more » « less
Award ID(s):
1923445
PAR ID:
10542328
Author(s) / Creator(s):
; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Biology of Reproduction
Volume:
108
Issue:
6
ISSN:
0006-3363
Page Range / eLocation ID:
960 to 973
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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