Interaction of caldesmon and myosin subfragment 1 with the C-terminus of actin.
The interactions of caldesmon and S1 with the C-terminus of actin were examined in co-sedimentation experiments using proteolytically truncated actin. It is shown that removal of 6 residues from the C-terminus of actin reduces the binding of caldesmon by about 50% while improving the binding of S1 to actin. We also show that S1 protects actin's C-terminus from enzymatic cleavage. Both S1 and caldesmon binding to actin are decreased in the presence of an actin C-terminal peptide. These results emphasize the importance of the C-terminus of actin in binding to S1 and caldesmon.
Crosbie
R H
RH
Department of Chemistry and Biochemistry, University of California, Los Angeles 90024.
Chalovich
J M
JM
Reisler
E
E
D000199:Actins / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005456:Fluorescent Dyes; D007106:Immune Sera; D007700:Kinetics; D008969:Molecular Sequence Data; D009132:Muscles / Q000378:metabolism; D015879:Myosin Subfragments / Q000302:isolation & purification / Q000378:metabolism*; D009282:Naphthalenesulfonates; D010446:Peptide Fragments / Q000302:isolation & purification / Q000378:metabolism*; D011485:Protein Binding; D011817:Rabbits
D000199:Actins; D002148:Calmodulin-Binding Proteins; D005456:Fluorescent Dyes; D007106:Immune Sera; D015879:Myosin Subfragments; D009282:Naphthalenesulfonates; D010446:Peptide Fragments; C006421:1,5-I-AEDANS