期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2002
卷号:99
期号:1
页码:483-488
DOI:10.1073/pnas.012593399
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Mutations in the gene encoding the peripheral myelin protein 22 (PMP22), a tetraspan protein in compact peripheral myelin, are one of the causes of inherited demyelinating peripheral neuropathy. Most PMP22 mutations alter the trafficking of the PMP22 protein in Schwann cells, and this different trafficking has been proposed as the underlying mechanism of the disease. To explore this problem further, we compared the aggregation of wild-type Pmp22 with those of the two Pmp22 mutations found in Trembler (Tr) and Trembler J (TrJ) mice. All three Pmp22s can be crosslinked readily as homodimers in transfected cells. Wild-type Pmp22 also forms heterodimers with Tr and TrJ Pmp22, and these heterodimers traffic with their respective mutant Pmp22 homodimers. All three Pmp22s form complexes larger than dimers with Tr Pmp22 especially prone to aggregate into high molecular weight complexes. Despite the differences in aggregation of Tr and TrJ Pmp22, these two mutant Pmp22s sequester the same amount of wild-type Pmp22 in heterodimers and heterooligomers. Thus, the differences in the phenotypes of Tr and TrJ mice may depend more on the ability of the mutant protein to aggregate than on the dominant-negative effect of the mutant Pmp22 on wild-type Pmp22 trafficking.