Open AccessTwo functionally redundant sources of retinoic acid secure spermatogonia differentiation in the seminiferous epithelium
Author(s) -
Marius Teletin,
Nadège Vernet,
Jianshi Yu,
Muriel Klopfenstein,
Jace W. Jones,
Betty Féret,
Maureen A. Kane,
Norbert B. Ghyselinck,
Manuel Mark
Publication year - 2018
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.15
H-Index - 36
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.170225
Subject(s) - retinoic acid , biology , spermatogenesis , microbiology and biotechnology , sertoli cell , meiosis , epithelium , tretinoin , spermatocyte , gene , medicine , endocrinology , genetics
In mammals, all- trans retinoic acid (ATRA) is instrumental to spermatogenesis. It is synthesized by two retinaldehyde dehydrogenases (RALDH) present in both Sertoli cells (SCs) and germ cells (GCs). In order to determine the relative contributions of each source of ATRA, we have generated mice lacking all RALDH activities in the seminiferous epithelium (SE). We show that both the SC- and GC-derived sources of ATRA cooperate to initiate and propagate spermatogenetic waves at puberty. In adults, they exert redundant functions and, against all expectations, the GC-derived source does not perform any specific roles despite contributing to two-thirds of the total amount of ATRA present in the testis. The production from SCs is sufficient to maintain the periodic expression of genes in SCs, as well and the cycle and wave of the SE, which account for the steady production of spermatozoa. The production from SCs is also specifically required for spermiation. Importantly, our study shows that spermatogonia differentiation depends upon the ATRA synthesized by RALDH inside the SE, whereas initiation of meiosis and expression of STRA8 by spermatocytes can occur without ATRA.