DMRT1、PKCIW和FET1是鸟类性别决定过程中重要的候选基因。以芳香化酶抑制剂处理的鸡胚为实验材料, 对这3个基因的表达变化进行了研究。结果表明, 在整个性别决定关键时期(E4.5 ~ E10.5), DMRT1在雄性的表达量显著高于雌性, 并且在ZW性反转鸡胚中表达大幅上升, 表明DMRT1的上调表达是与睾丸形成相关的。PKCIW基因在雌性特异表达并在性反转鸡胚表达上升, 这可能与其特殊作用模式有关, 即使性反转鸡胚PKCIW代偿性的表达升高, 却也未能阻止睾丸的形成。此外, FET1为雌性特异表达, 但在性反转鸡胚中表达无变化。综上, 实验结果支持了DMRT1是鸟类睾丸发育决定因子的假说。

Dsx and mab-3-related transcription factor (DMRT1), Protein kinase C inhibitor (PKCIW) and Female-specific expression transcription factor (FET1) have been regarded as critical candidates of avian sex determination. Their mRNA expression was analyzed in chicken embryos during experimentally induced female-to-male sex-reversal by an aromatase inhibitor (AI) fadrozole. DMRT1 expression was higher in male (ZZ) gonads than in female (ZW) gonad prior to and throughout the pe-riod of sex differentiation. However, female-to-male sex-reversed ZW embryos showed elevated levels of DMRT1 expres-sion similar to those of normal males, indicating that DMRT1 was associated with testis development. PKCIW gene expres-sion was dimorphic between male and female gonads, and was up-regulated in AI-treated female embryos. This finding might account for the specific effect of PKCIW, functioning via heterodimerization with PKCI during avian sex determina-tion. However, its elevated expression appeared to be insufficient to induce ovary development. On the other hand, FET1 expression was female-specific and unchanged in AI-treated female embryos. Results of present experiment suggested that DMRT1 is a determinant for testis development in birds.