|Matsuzaki, F., Matsumoto, S.,
Yahara, I., Yonezawa, N., Nishida,
E. & Sakai, H. (1988) Cloning and Characterization of Porcine Brain
Cofilin cDNA. J. Biol. Chem. 263, 11564-11568.
Cofilin is a widely distributed, pH-sensitive, actin-modulating protein
with an apparent molecular mass of 21 kDa, which forms
intranuclear and/or cytoplasmic actin/cofilin rods in
cultured fibroblastic cells under specific conditions. In
this study, a cDNA library from porcine brain mRNA was
constructed, and full-length brain cofilin cDNA clones were isolated by
screening with oligonucleotide probes. The deduced amino acid
sequence of cofilin is 166 residues long and contains a
sequence of Lys-Lys-Arg-Lys-Lys which is very similar to the
nuclear transport signal sequence (Pro-Lys-Lys-Lys-Arg-Lys-Val)
of SV40 large T antigen. The sequence may act as a signal
capable of inducing nuclear accumulation of cofilin in cells exposed
to heat shock or dimethyl sulfoxide. The cofilin sequence contains a
hexapeptide (Asp-Ala-Ile-Lys- Lys-Lys) identical to the amino-terminal
sequence (residues 2-7) of muscle and nonmuscle tropomyosin.
Cofilin also has in the carboxyl- terminal portion a region
homologous to the sequence shared by gelsolin, fragmin, and Acanthamoeba
profilin. Furthermore, the overall amino acid sequence of
cofilin shows weak homology with the rod portion of myosin
and suggests a high alpha-helical content.