Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
Sci China Life Sci. 2011 Nov;54(11):1005-10. doi: 10.1007/s11427-011-4240-4. Epub 2011 Dec 16.
Pod1 is a member of the basic helix-loop-helix (bHLH) family of transcription factors that have been implicated in the regulation of sexual differentiation and gonadal development in mammals. However, to date, little is known about the role of Pod1 in nonmammalian vertebrate gonadogenesis. We cloned and characterized the Pod1 gene from tilapia. The tilapia Pod1 gene contains an open reading frame (ORF) of 525 nucleotides which potentially codes for a protein with 174 amino acids. Sequence alignment revealed that the deduced tilapia protein sequence shared high homology (79.5% to 90.5%) with the Pod1 sequences of other vertebrates. The tissue distribution of Pod1 revealed by RT-PCR showed that it had varied expression patterns in adult tilapia. In situ hybridization was performed to examine the temporal and spatial expression patterns of Pod1 during tilapia sexual differentiation and gonadal development. In the undifferentiated gonad, Pod1 was expressed in the somatic cells of both sexes. Subsequently, Pod1 expression in tilapia persisted in differentiated juvenile and adult ovary and testis. Our data indicate for the first time that Pod1 is not only necessary for the onset of sexual differentiation, but also plays an important role in gonadal development in the teleost.
Pod1 是基本螺旋-环-螺旋（bHLH）转录因子家族的成员，该家族参与哺乳动物的性分化和性腺发育的调控。然而，迄今为止，人们对 Pod1 在非哺乳动物脊椎动物性腺发生中的作用知之甚少。我们从罗非鱼中克隆并鉴定了 Pod1 基因。罗非鱼 Pod1 基因包含一个 525 个核苷酸的开放阅读框（ORF），可能编码一个由 174 个氨基酸组成的蛋白质。序列比对表明，推导的罗非鱼蛋白序列与其他脊椎动物的 Pod1 序列具有高度同源性（79.5%至 90.5%）。通过 RT-PCR 显示的 Pod1 的组织分布表明，它在成年罗非鱼中有不同的表达模式。原位杂交用于研究 Pod1 在罗非鱼性分化和性腺发育过程中的时空表达模式。在未分化的性腺中，Pod1 在两性的体细胞中表达。随后，Pod1 在分化的幼鱼和成年卵巢和睾丸中的表达持续存在。我们的数据首次表明，Pod1 不仅是性分化开始所必需的，而且在硬骨鱼的性腺发育中也起着重要作用。
