Analysis of the roles of the head domains of type IV rat neuronal intermediate filament proteins in filament assembly using domain-swapped chimeric proteins

摘要: Type IV neuronal intermediate filament proteins consist of alpha-internexin, which can self-assemble into filaments and the neurofilament triplet proteins, are obligate heteropolymers, at least in rodents. These IF therefore provide good systems for elucidating mechanism assembly. To analyze roles head domains these contributing to their differential assembly properties, we generated chimeric by swapping between rat alpha-internexin either NF-L or NF-M examined properties transfected cells that lack own cytoplasmic network. Lalphaalpha Malphaalpha, replacing domain with those NF-M, respectively, were unable filaments. In contrast, alphaLL, a protein was able filaments, whereas MLL, containing domain, do so. results demonstrate is essential alpha-internexin's ability self-assemble. While coassembly Malphaalpha resulted formation yielded punctate patterns. show heteropolymeric requires one partner has other domain. Thus, play important determining nature formation. The data obtained from self-assembly studies some new insights