小鼠免疫抑制蛋白SOCS3脯氨酸富集区为其生物学功能所必需

Proline-rich Region in Immune Suppression Protein SOCS3 is Required for Its Biological Functions

SOCS3（suppressors of cytokine signaling 3）可以调节信号转导过程并影响造血干细胞的分化.利用生物信息学方法,发现SOCS3蛋白含有脯氨酸富集区,采用重组PCR技术缺失SOCS3蛋白中的129-161位的氨基酸（SOCS3Δ129-161）,并将其克隆到pcDNA31/V5质粒载体中.转染细胞,然后通过流式细胞技术,分析预测的功能区对SOCS3蛋白功能的影响.结果表明,此脯氨酸富集区对SOCS3蛋白的三级结构和功能有重要的意义.建模结果显示,SOCS3Δ129-161蛋白结构发生显著变化.脯氨酸富集区的缺失也影响小鼠骨髓细胞向CD8^＋T细胞分化.研究结果显示,SOCS3蛋白中129-161位的脯氨酸富集区在其结构和功能上有重要的作用.

Suppressor of cytokine signaling 3 （SOCS3） negatively regulates signal transduction and exerts an important role in regulating the differentiation of hematopoietic cells. SOCS3 contains an proline-rich region as determined by bioinformatics-based analysis. To determine the role of this proline-rich region, the deletion mutant of SOCS3 amino acids 129- 161 （SOCS3△129-161） was obtainde using PCR and then cloned into pcDNA31/V5 recombinant plasmid. The functions of SOCS3△129-161were analyzed by flow cytometry in transfected cells. The results showed that the three-dimensional structure of SOCS3△129-161 was clearly different from that of wildtype as predicted by comparative（homology） computation modeling. In addition, the SOCS3△129-161 abrogated the functions of native SOCS3, inducing CD8^＋ T cell differentiation. The results suggested that the proline-rich region within amino acids 129 - 161 of SOCS3 might play an important role in the formation and maintaining of SOCS3 tertiary structure and significantly contributed for its biological functions.