The poly(C)-binding protein (PCBP) family members belong to a subtype of RNA-binding proteins that are ubiquitously expressed with diverse functions. In mammals, PCBP family, also known as hnRNP E family, is composed of four proteins, namely PCBP1, PCBP2, PCBP3 and PCBP4. So far, no study has been documented on the physiological roles of each member in vertebrate development. Here we analysed the spatiotemporal expression patterns of zebrafish (Danio rerio) pcbp2 (identical to pcbp1 and pcbp2 in mammals), pcbp3 and pcbp4 at various stages of zebrafish embryonic development by whole-mount in situ hybridization. Our results revealed that all pcbp genes are maternally expressed, especially pcbp2, which is strongly expressed from the embryogenetic stage to larva. The expression patterns of PCBP members are similar to each other at the very early developmental stage sharing with common strong expression in the intestine, otic vesicle, retina and brain of zebrafish. Subsequently, the messenger RNAs of PCBP members are gradually constrained and highly expressed in intestines of the larvae. Collectively, our study figured out the expression pattern of each PCBP member in diverse organogenesis during embryo development, indicating that PCBP members may play predominant roles in the development of neural and digestive systems to maintain their normal physiological functions. Moreover, the similar expression patterns at the developmental stages and organ types among this family suggest that the aberrant expression of these genes would lead to the neural or intestinal diseases.

聚（C）结合蛋白（PCBP）家族成员属于RNA结合蛋白的一种亚型，它以各种功能无处不在地表达。在哺乳动物中，PCBP家族（也称为hnRNP E家族）由四种蛋白质组成，即PCBP1，PCBP2，PCBP3和PCBP4。到目前为止，还没有关于脊椎动物发育中每个成员的生理作用的研究文献。在这里，我们通过整体安装原位杂交分析了斑马鱼胚胎发育不同阶段的斑马鱼（Danio rerio）pcbp2（与哺乳动物中的pcbp1和pcbp2相同），pcbp3和pcbp4的时空表达模式。我们的结果表明，所有pcbp基因在母亲中表达，尤其是pcbp2从胚发生阶段到幼虫强烈表达。PCBP成员的表达模式在早期发育阶段彼此相似，在斑马鱼的肠，耳囊，视网膜和脑中共同表达。随后，PCBP成员的信使RNA逐渐受到限制，并在幼虫的肠道中高度表达。总体而言，我们的研究指出了胚胎发育过程中每个PCBP成员在不同器官发生过程中的表达模式，这表明PCBP成员在神经和消化系统的发育中可能起主要作用，以维持其正常的生理功能。此外，