The identity of germ cells, the progenitors of life, is thought to be acquired by two modes; either by maternal signals (preformed) or induced de novo from pluripotent cells (epigenesis) in the developing embryos. However, paternal roles seem enshrouded or completely overlooked in this fundamental biological process. Hence, we investigated the presence of germplasm transcripts in the sperm of Gambusia holbrooki, a live-bearing fish, demonstrating their presence and suggesting paternal contributions. Interestingly, not all germplasm markers were present (nanos1 and tdrd6) in the sperm, but some were conspicuous (dazl, dnd-α, piwi II, and vasa), indicating that the latter is required for establishing germ cell identity in the progeny, with a possible parent-specific role. Furthermore, there were also spatial differences in the distribution of these determinants, suggesting additional roles in sperm physiology and/or fertility. Our results support the hypothesis that dads also play a vital role in establishing the germ cell identity, especially in G. holbrooki, which shares elements of both preformation and induction modes of germline determination. This, coupled with its life history traits, makes G. holbrooki an excellent system for dissecting evolutionary relationships between the two germline determination modes, their underpinning mechanisms and ultimately the perpetuity of life.
History
Sub-type
Article
Publication title
DEVELOPMENTAL BIOLOGY
Medium
Print-Electronic
Volume
502
Pagination
14-19:6
eISSN
1095-564X
ISSN
0012-1606
Department/School
Ecology and Biodiversity, Sustainable Marine Research Collaboration
Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
Publication status
Published
Place of publication
United States
Event Venue
Laboratory of Molecular Biology, Institute for Marine and Antarctic Studies, University of Tasmania, Taroona, TAS, 7053, Australia.