Assembly of carboxy-terminally deleted desmin in vimentin-free cells.
Using a vimentin-free expression system we were able to demonstrate that the carboxy terminus of desmin is necessary for filament assembly in the living cell. Desmin subunits missing only 4 carboxy-terminal residues of their rod domain are incapable of homopolymeric filament assembly. Moreover, even single amino acid substitutions in the conserved carboxy-terminal part of the rod domain prevent desmin subunits from homopolymeric filament assembly. Desmin subunits missing 18 or more carboxy-terminal residues of their rod domain (including the complete conserved carboxy-terminal region) are unstable in cells devoid of intact type III intermediate filaments (IFs). Interaction with an intact type III IF, however, stabilizes these mutated desmin subunits. Expression of a desmin subunit missing both its non-helical end domains in vimentin-containing cells disrupts the endogenous vimentin network completely.
Raats
J M
JM
Department of Biochemistry, University of Nijmegen, The Netherlands.
Henderik
J B
JB
Verdijk
M
M
van Oort
F L
FL
Gerards
W L
WL
Ramaekers
F C
FC
Bloemendal
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002872:Chromosome Deletion; D006224:Cricetinae; D004252:DNA Mutational Analysis; D003893:Desmin / Q000235:genetics* / Q000378:metabolism*; D000939:Epitopes; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D007382:Intermediate Filaments / Q000378:metabolism*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D014162:Transfection; D014746:Vimentin / Q000235:genetics* / Q000378:metabolism
D003893:Desmin; D000939:Epitopes; D046911:Macromolecular Substances; D014746:Vimentin