The sequence of a cytoplasmic intermediate filament (IF) protein from the annelid Lumbricus terrestris emphasizes a distinctive feature of protostomic IF proteins.
The complete cDNA clone for a cytoplasmic intermediate filament (IF) protein from the annelid Lumbricus terrestris reported here, shows an extra 42 residues in the coil 1b subdomain of the central rod, as do the IF proteins from nematodes and molluscs. These extra six heptads are also present in all nuclear lamins but not in any known vertebrate cytoplasmic IF protein. Thus, it seems that protostomic metazoa conserve a lamin-like structural element in their cytoplasmic IF proteins, which was lost in the deuterostomic metazoan branch leading to the vertebrates.
Bovenschulte
M
M
Max Planck Institute for Biophysical Chemistry, Department of Biochemistry, Goettigen, Germany.
Riemer
D
D
Weber
K
K
D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D002107:Caenorhabditis / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D049832:Decapodiformes / Q000235:genetics; D007381:Intermediate Filament Proteins / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000737:chemistry* / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D007381:Intermediate Filament Proteins