Expression profile of male germ cell‐associated genes in mouse embryonic stem cell cultures treated with all‐trans retinoic acid and testosterone

Abstract

Cells that morphologically and functionally resemble male germ cells can be spontaneously derived from ES cells. However, this process is inefficient and unpredictable suggesting that the expression pattern of male germ cell associated genes during spontaneous ES cell differentiation does not mimic the in vivo profiles of the genes. Thus, in the present study, the temporal expression profile of genes expressed at different stages of male germ cell development was examined in differentiating ES cells. The effect of all-trans retinoic acid (RA) which is a known inducer of primordial germ cell (PGC) proliferation/survival in vitro and testosterone which is required for spermatogenesis in vivo on the expression of these genes was also determined. Each of the 12 genes analyzed exhibited one of four temporal expression patterns in untreated differentiating ES cells: progressively decreased (Dpp3a, Sycp3, Msy2), initially low and then increased (Stra8, Sycp1, Dazl, Act, Prm1), initially decreased and then increased (Piwil2, Tex14), or relatively unchanged (Akap3, Odf2). RA-treated cells exhibited increased expression of Stra8, Dazl, Act, and Prm1 and suppressed expression of Dpp3a compared to untreated controls. Furthermore, testosterone increased expression of Stra8 while the combination of RA and testosterone synergistically increased expression of Act. Our findings establish a comprehensive profile of male germ cell gene expression during spontaneous differentiation of murine ES cells and describe the capacity of RA and testosterone to modulate the expression of these genes. Furthermore, these data represent an important first step in designing a plausible directed differentiation protocol for male germ cells.

In vitro germ cell differentiation from embryonic stem cells of mice: induction control by BMP4 signalling

“…Our results also showed the expression of Stra8 in CCE mouse ESCs and increased expression of this gene was observed very early in EB development. A similar result was obtained by Silva et al [33] in a study showing that Stra8 gene was expressed in undifferentiated TL-1 Sv129 mouse XY ES cells and increased with EB formation and differentiation. Mouse Stra8 express in male germ cells from E14.5 to spermatogonia.…”

Isolation, genetic manipulation, and transplantation of canine spermatogonial stem cells: progress toward transgenesis through the male germ-line

“…Mouse SSC can also be converted into pluripotent cells, without genetic manipulation (Guan et al 2006, Conrad et al 2008, Izadyar et al 2008, Golestaneh et al 2009b, Mizrak et al 2010). These germ line-derived pluripotent cells (gPS) acquire an expression profile similar to embryonic stem cells (ESC; (Silva et al 2009)), and are functionally indistinguishable from ESC: They form complex teratomas, differentiate into three germ layers in culture, and contribute to all the tissues of mice generated from chimeric blastocysts (Takehashi et al 2007, Conrad et al 2008, Izadyar et al 2008). Thus, at least in the mouse, SSCs provide an unusually versatile source of material for stem cell and developmental research, including transgenic animal technology, and stem cell-based cell therapy.…”

Screening for self-renewal factors by a combination of mRNA and CGH microarray in human embryonic stem cells

“…Tex14 encodes a predicted protein with 2 protein kinase domains which is expressed mainly in male germ cells. Tex14 exhibits an expression profile in untreated differentiating ESCs: initially decreased and then increased, and high expression of Tex14 is detected in undifferentiated ESC (Silva et al, 2009). Therefore, Tex14 is important for male germ cell maturity, and might be involved in pluripotency maintenance.…”