Hempel Leonie U, Oliver Brian
Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, 50 South Drive, Bethesda MD 20892 USA.
BMC Dev Biol. 2007 Oct 12;7:113. doi: 10.1186/1471-213X-7-113.
In Drosophila melanogaster, a pre-mRNA splicing hierarchy controls sexual identity and ultimately leads to sex-specific Doublesex (DSX) transcription factor isoforms. The male-specific DSXM represses genes involved in female development and activates genes involved in male development. Spatial and temporal control of dsx during embryogenesis is not well documented.
Here we show that DSX(M) is specifically expressed in subsets of male somatic gonad cells during embryogenesis. Following testis formation, germ cells remain in contact with DSX(M)-expressing cells, including hub cells and premeiotic somatic cyst cells that surround germ cells during spermatogenesis in larval and adult testes.
We show that dsx is transcriptionally regulated in addition to being regulated at the pre-mRNA splicing level by the sex determination hierarchy. The dsx locus is spatially controlled by somatic gonad identity. The continuous expression of DSX(M) in cells contacting the germline suggests an ongoing short-range influence of the somatic sex determination pathway on germ cell development.
在黑腹果蝇中,前体mRNA剪接层级控制性别特征,并最终导致性别特异性的双性(DSX)转录因子异构体。雄性特异性的DSXM抑制参与雌性发育的基因,并激活参与雄性发育的基因。胚胎发育过程中dsx的时空控制尚未得到充分记录。
我们在此表明,DSX(M)在胚胎发育过程中特异性表达于雄性体细胞性腺细胞亚群中。睾丸形成后,生殖细胞与表达DSX(M)的细胞保持接触,包括在幼虫和成年睾丸精子发生过程中包围生殖细胞的中心细胞和减数分裂前的体细胞囊肿细胞。
我们表明,dsx除了在性别决定层级的前体mRNA剪接水平受到调控外,还受到转录调控。dsx基因座受体细胞性腺特征的空间控制。DSX(M)在与生殖系接触的细胞中的持续表达表明体细胞性别决定途径对生殖细胞发育存在持续的短程影响。