Vdovina Yulia A, Kurshakova Maria M, Georgieva Sofia G, Kopytova Daria V
Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia.
Curr Issues Mol Biol. 2023 Jul 4;45(7):5662-5676. doi: 10.3390/cimb45070357.
PCID2 is a subunit of the TREX-2 mRNA nuclear export complex. Although the complex has long been studied in eukaryotes, it is still unclear how TREX-2 interacts with mRNA in multicellular organisms. Here, the interaction between PCID2 and the RNA was studied by EMSA. We show that the C-terminal region of the WH domain of PCID2 specifically binds the 3'-noncoding region of the RNA. While the same region of PCID2 interacts with the Xmas-2 subunit of the TREX-2 complex, PCID2 interacts with RNA independently of Xmas-2. An additional RNA-binding region (M region) was identified in the N-terminal part of the PCI domain and found to bind RNA nonspecifically. Point mutations of evolutionarily conserved amino acid residues in this region completely abolish the PCID2-RNA interaction, while a deletion of the C-terminal domain only partly decreases it. Thus, the specific interaction of PCID2 with RNA requires nonspecific PCID2-RNA binding.
PCID2是TREX-2 mRNA核输出复合体的一个亚基。尽管该复合体在真核生物中已被研究多年，但在多细胞生物中TREX-2如何与mRNA相互作用仍不清楚。在此，通过电泳迁移率变动分析（EMSA）研究了PCID2与RNA之间的相互作用。我们发现PCID2的WH结构域的C末端区域特异性结合RNA的3'-非编码区。虽然PCID2的同一区域与TREX-2复合体的Xmas-2亚基相互作用，但PCID2与RNA的相互作用独立于Xmas-2。在PCI结构域的N末端部分鉴定出一个额外的RNA结合区域（M区域），发现它能非特异性结合RNA。该区域中进化保守氨基酸残基的点突变完全消除了PCID2与RNA的相互作用，而C末端结构域的缺失仅部分降低了这种相互作用。因此，PCID2与RNA的特异性相互作用需要PCID2与RNA的非特异性结合。
