Differentiation of female primordial germ cells in the male testes of chicken (Gallus gallus domesticus)

Abstract

In our previous studies, we demonstrated that female primordial germ cells (PGCs) have the ability to differentiate into W chromosome-bearing (W-bearing) spermatozoa in male gonads of germline chimeric chickens. In this study, to investigate the differentiation pattern of female PGCs in male gonads in chickens, three germline chimeric chickens were generated by injecting female PGCs into the male recipient embryos. After these male chimeras reached sexual maturity, the semen samples were analyzed for detecting W-bearing cells by PCR and in situ hybridization analyses. The results indicated that the female PGCs had settled and differentiated in their testes. A histological analysis of the seminiferous tubule in those chimeras demonstrated that the W-bearing spermatogonia, spermatocytes, and round spermatids accounted for 30.8%, 32.7%, and 28.4%, respectively. However, the W-bearing elongating spermatid was markedly lower (7.7%) as compared to the W-bearing round spermatid. The W-bearing spermatozoa were hardly ever observed (0.2%). We concluded that although female PGCs in male gonads are capable of passing through the first and second meiotic division in adapting themselves to a male environment, they are hardly complete spermiogenesis.

Reproduction of Wild Birds via Interspecies Germ Cell Transplantation1

“…Tagami et al [24] reported that female PGCs (ZW germ cells) could differentiate into both Z-bearing and W-bearing spermatozoa in the male testis. Concomitantly, however, they assumed that ZW germ cells were restricted at some point during spermatogenesis.…”

Production of Pure Hinai-dori with Normal Reproductive Capability from Transferred Primordial Germ Cells

“…The frequency of donor-derived offspring from germline chimeras is significantly higher for donor PGCs and recipient embryos of the same-sex compared with different-sex combinations (Naito et al, 1999). Tagami et al (2007) reported that female PGCs in male gonads passed through the first and second meiotic divisions by adapting themselves to the male environment; however, their ability to complete spermatogenesis was limited. Therefore, it is thought that there is some possibility of mixture sex.…”

Embryo Manipulation in Chickens

“…When female PGCs (ZW) were transferred to male recipient embryos, Z-bearing spermatozoa derived from female PGCs could be produced to give rise to functional offspring. W-bearing spermatozoa were also produced, but no functional offspring have been generated so far from the mixed-sex germline chimeric chickens (Kagami et al, 1995(Kagami et al, , 1997Tagami et al, 1997Tagami et al, , 2007Naito et al, 1999). Recently, gonadal germ cells isolated from the gonads of 7-day incubated embryos were transferred to the recipient embryos and succeeded to produce same-sex and mixed-sex germline chimeric chickens (Nakajima et al, 2014).…”