Abstract:
Sex chromosomes underlie the development of male or female sex organs across species. While systemic signals derived from sex organs prominently contribute to sex-linked differences, it is unclear whether the intrinsic presence of sex chromosomes in somatic tissues has a specific function. Here, we use genetic tools to show that cellular sex is crucial for sexual differentiation throughout the body in Drosophila melanogaster. We reveal that every somatic cell converts the intrinsic presence of sex chromosomes into the active production of a sex determinant, a female specific serine- and arginine-rich (SR) splicing factor. This discovery dismisses the mosaic model which posits that only a subset of cells has the potential to sexually differentiate. Using cell-specific sex reversals, we show that this prevalence of cellular sex drives sex differences in organ size and body weight and is essential for fecundity. These findings demonstrate that cellular sex drives differentiation programs at an organismal scale and highlight the importance of cellular sex pathways in sex trait evolution.
摘要:
性染色体是跨物种的男性或女性性器官发育的基础。虽然来自性器官的系统信号显著地导致了与性别相关的差异,尚不清楚性染色体在体细胞组织中的内在存在是否具有特定功能。这里,我们使用遗传工具表明细胞性别对于黑腹果蝇整个身体的性分化至关重要。我们发现,每个体细胞都将性染色体的内在存在转化为性别决定子的主动产生,女性特异性富含丝氨酸和精氨酸(SR)的剪接因子。这一发现驳回了镶嵌模型,该模型认为只有一部分细胞具有性分化的潜力。利用细胞特异性逆转,我们表明,细胞性的这种流行导致器官大小和体重的性别差异,并且对繁殖力至关重要。这些发现表明,细胞性别在生物体尺度上驱动分化程序,并强调了细胞性途径在性特征进化中的重要性。