hnRNP K的结构及功能

Structure and Function of hnRNP K

核内不均一性核糖核蛋白K（heterogeneous nuclear ribonucleoprotein K，hnRNP K）最早在hnRNA加工过程中被发现，属于hnRNP家族的一员。研究表明hnRNPK的主要功能结构为3个引导DNA—RNA连接的KH域和一个独特的KI域。hnRNP K不仅能够通过依赖CT元件的途径或不依赖CT元件的途径在转录水平上对基因表达进行调控，还能够通过自身的磷酸化，改变mRNA的翻译效率，以及调控基因翻译及转导胞内信号。此外，hnRNP K与肿瘤发生和转移的关系也是近年来的研究热点。hnRNP K被发现在许多肿瘤组织中高表达，主要通过调控与细胞增殖有关的基因表达而影响肿瘤的发生发展，同时它与肿瘤细胞的扩散转移也有关。

Heterogeneous nuclear ribonucleoprotein K （ hnRNP K） , a member of hnRNP pro- tein family, was first discovered during the processing of hnRNA. Its functional structures are mainly composed of three KH domains that induce DNA-RNA binding and a unique KI domain, hnRNP K can not only regulate gene expression through CT-dependent or CT-independent pathways in the pro- gress of transcription, but also modulate the efficiency of mRNA translation by its phosphorylation, indicating its functional effect on gene translation regulation and intracellular signal transduction. It has been reported that hnRNP K plays a role in tumor occurrence and development by regulating the expression level of cell proliferation related genes. And hnRNP K is also related to tumor spread.