Abstract:
The sex chromosomes of birds are designated Z and W. The male is homogamous (ZZ), and the female is heterogamous (ZW). The chicken W chromosome is a degenerate version of the Z chromosome and harbors only 28 protein-coding genes. We studied the expression pattern of the W chromosome gene MIER3 (showing differential expression during gonadogenesis) in chicken embryonic gonads and its potential role in gonadal development. The W copy of MIER3 (MIER3-W) shows a gonad-biased expression in chicken embryonic tissues which was different from its Z copy. The overall expression of MIER3-W and MIER3-Z mRNA and protein is correlated with the gonadal phenotype being higher in female gonads than in male gonads or female-to-male sex-reversed gonads. Chicken MIER3 protein is highly expressed in the nucleus, with relatively lower expression in the cytoplasm. Overexpression of MIER3-W in male gonad cells suggested its effect on the GnRH signaling pathway, cell proliferation, and cell apoptosis. MIER3 expression is associated with the gonadal phenotype. MIER3 may promote female gonadal development by regulating EGR1 and αGSU genes. These findings enrich our knowledge of chicken W chromosome genes and support a more systematic and in-depth understanding of gonadal development in chickens.
摘要:
鸟类的性染色体被命名为Z和W。雄性是同妻制(ZZ),女性是异性恋(ZW)。鸡W染色体是Z染色体的简并版本,仅包含28个蛋白质编码基因。我们研究了W染色体基因MIER3(在性腺发生过程中显示差异表达)在鸡胚胎性腺中的表达模式及其在性腺发育中的潜在作用。MIER3的W拷贝(MIER3-W)在鸡胚胎组织中显示性腺偏向性表达,其不同于其Z拷贝。MIER3-W和MIER3-ZmRNA和蛋白的总体表达与女性性腺的性腺表型高于男性性腺或女性对男性性逆转性腺有关。鸡MIER3蛋白在细胞核中高表达,在细胞质中的表达相对较低。MIER3-W在男性性腺细胞中的过表达提示其对GnRH信号通路的影响,细胞增殖,和细胞凋亡。MIER3表达与性腺表型相关。MIER3可能通过调节EGR1和αGSU基因促进雌性性腺发育。这些发现丰富了我们对鸡W染色体基因的认识,支持了对鸡性腺发育的更系统和深入的认识。