带4.2蛋白是一种重要的红细胞膜蛋白,与红细胞的形态、可变形性及携氧功能有至关重要的联系。它通过与带3蛋白(阴离子通道蛋白)、锚蛋白结合,稳定的连接在细胞膜的内表面,连接着膜骨架网架结构与细胞膜,是膜骨架与脂质双分子层连接的重要纽带。带4.2蛋白的缺失会引起球形或椭圆形红细胞增多症及不同程度的溶血性贫血,严重的情况需要摘除脾脏来进行治疗。近年来研究认为,带4.2蛋白在维持细胞膜骨架的完整性和稳定性方面扮演了重要角色。现对带4.2蛋白结构及功能的研究状况进行综述。
Protein 4.2 is a major erythrocyte membrane skeletal protein which has been immunologically detected in a variety of cell types and is apparently essential for normal erythrocyte membrane function. It is a transglutaminase-like molecule with no enzymatic cross-linking activity. Protein 4.2 associates with the cytoplasmic domain of band 3 and interacts with ankyrin in the erythrocyte membrane. Protein 4.2 is N-myristylated. It is playing an important role in maintaining the integrity and stability of the membrane. Individuals with protein 4.2 deficiency in their erythrocyte membranes exhibit spherocytosis and experience various degrees of hemolytic anemia, which may necessitate a splenectomy. In humans, several point mutations and a frame shift mutation of protein 4.2 are associated with protein 4.2 deficiency in hemolytic anemia. Band 4.2 may serve as an accessory linking protein between the membrane skeleton and the overlying lipid bilayer. This article has reviewed the progress of the research on the construction and the function of protein 4.2.