Characterization of F-actin bundling activity of Tetrahymena elongation factor 1 alpha investigated with rabbit skeletal muscle actin.
Elongation factor 1 alpha (EF-1 alpha) is an essential factor for protein synthesis in eukaryotes. Here, we demonstrated that Tetrahymena EF-1 alpha induced bundles of rabbit skeletal muscle F-actin as well as Tetrahymena F-actin in vitro, although Tetrahymena and skeletal muscle actins are different in some parts of their primary structures and in the binding abilities to some actin-binding proteins. Co-sedimentation experiments showed that the binding ratio of Tetrahymena EF-1 alpha to skeletal muscle F-actin in the bundles was 1 : 1. Electron microscopic observation showed that alkaline pH or high ionic strength reduced the bundling activity of Tetrahymena EF-1 alpha to some extent, although the EF-1 alpha seemed to be able to induce bundling of the F-actin within the range of physiological condition.
Kurasawa
Y
Y
Institute of Biological Sciences, University of Tsukuba, Ibaraki, Japan.
Watanabe
Y
Y
Numata
O
O
D000199:Actins / Q000378:metabolism*; D000818:Animals; D006863:Hydrogen-Ion Concentration; D018482:Muscle, Skeletal / Q000378:metabolism*; D009994:Osmolar Concentration; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors / Q000378:metabolism*; D011485:Protein Binding; D011817:Rabbits; D013768:Tetrahymena / Q000378:metabolism*
D000199:Actins; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors