CD34分子的胞外结构域cDNA分离与表达

ISOLATION AND EXPRESSION OF CD34 EXTRACELLULAR DOMAIN

CD34分子是一种重要的造血干 /祖细胞表面标志 ,广泛用于造血干 /祖细胞的鉴定和分选。由于CD34分子具有受体样结构并能传递细胞同型聚集的信号 ,故它是一种信号分子 ,但其在造血系统的天然配体与确切的生理功能至今仍不明确。研究中我们分离了CD34分子的细胞外结构域cDNA ,并进行了原核融合表达及纯化。DNA序列分析和竞争结合抑制实验证明我们获得了纯化的CD34分子的细胞外结构域的重组蛋白 ,可作为CD34可溶性受体 。

CD34 molecule is an important hematopoietic stem/progenitor cell s u r face marker, which has been used for identifying and sorting hematopoietic stem / progenitor cells. It is also a signaling molecule because it has receptor like s tructure and can transduce signal for cell homotypic adhesion. However, the nat ural ligand and exact biological function of the CD34 molecule in hematopoietic system have not been clearly identified yet. In this study ,we isolated the ext racellular domain of the CD34 cDNA and expressed as a fusion protein. The result s from DNA sequencing and specific binding assay demonstrated that we have obtai ned a purified recombinant protein of the extracellular domain of CD34 molecule. It will be very helpful for our further studies on the physiological significan ce of the CD34 molecule.