AN ENDOGENOUS MDCK LYSOSOMAL MEMBRANE GLYCOPROTEIN IS TARGETED BASOLATERALLY BEFORE DELIVERY TO LYSOSOMES

被引:113
作者
NABI, IR
LEBIVIC, A
FAMBROUGH, D
RODRIGUEZBOULAN, E
机构
[1] FAC SCI LUMINY,DIFFERENCIAT CELLULAIRE LAB,F-13288 MARSEILLE 9,FRANCE
[2] JOHNS HOPKINS UNIV,DEPT BIOL,BALTIMORE,MD 21218
关键词
D O I
10.1083/jcb.115.6.1573
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Using surface immunoprecipitation at 37-degrees-C to "catch" the transient apical or basolateral appearance of an endogenous MDCK lysosomal membrane glycoprotein, the AC17 antigen, we demonstrate that the bulk of newly synthesized AC17 antigen is polarly targeted from the Golgi apparatus to the basolateral plasma membrane or early endosomes and is then transported to lysosomes via the endocytic pathway. The AC17 antigen exhibits very similar properties to members of the family of lysosomal-associated membrane glycoproteins (LAMPs). Parallel studies of an avian LAMP, LEP100, transfected into MDCK cells revealed colocalization of the two proteins to lysosomes, identical biosynthetic and degradation rates, and similar low levels of steady-state expression on both the apical (0.8%) and basolateral (2.1%) membranes. After treatment of the cells with chloroquine, newly synthesized AC17 antigen, while still initially targeted basolaterally, appears stably in both the apical and basolateral domains, consistent with the depletion of the AC17 antigen from lysosomes and its recycling in a nonpolar fashion to the cell surface.
引用
收藏
页码:1573 / 1584
页数:12
相关论文
共 66 条