Evidence for a conserved role of retinoic acid in urodele amphibian meiosis onset.
Pleurodeles waltl is a urodele amphibian displaying a ZZ/ZW genetic mode of sex determination. Gonad differentiation can later be modulated by hormone treatment. To investigate germ cell differentiation, we analyzed the expression of the meiosis marker PwDmc1 and show that germ cells enter meiosis in late larval life in females, and 2 months after metamorphosis in males. Organotypic cultures of gonad-mesonephros complexes demonstrated that retinoic acid triggers meiosis entry in P. waltl. In vivo analyses of both PwRaldh2 and PwCyp26b1 expressions, the enzymes required for RA synthesis and degradation respectively, indicate that meiosis onset depends on PwCyp26b1 repression in the gonad during normal or steroid-induced sex-reversed development. Taken together, our results show that RA-dependent meiosis entry could be a conserved mechanism of germ cell differentiation in vertebrates and provide evidence for crosstalk between steroid and RA signaling in the course of sex differentiation. Developmental Dynamics 238:1389-1398, 2009. (c) 2009 Wiley-Liss, Inc.
Wallacides
Angelina
A
EA 3442 Aspects Cellulaires et Moléculaires de la Reproduction et du Développement, Nancy-Université, Nancy, France.
Chesnel
Amand
A
Chardard
Dominique
D
Flament
Stéphane
S
Dumond
Hélène
H
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D005260:Female; D005854:Germ Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D008297:Male; D008540:Meiosis / Q000187:drug effects*; D008675:Metamorphosis, Biological; D010053:Ovary / Q000166:cytology / Q000187:drug effects; D010999:Pleurodeles / Q000196:embryology* / Q000502:physiology; D000072516:Retinoic Acid 4-Hydroxylase; D019849:Sex Determination Processes; D015398:Signal Transduction / Q000502:physiology; D013737:Testis / Q000166:cytology / Q000187:drug effects; D046509:Tissue Culture Techniques; D014212:Tretinoin / Q000378:metabolism / Q000494:pharmacology*
D015415:Biomarkers; D014212:Tretinoin; D003577:Cytochrome P-450 Enzyme System; D000072516:Retinoic Acid 4-Hydroxylase