The rôle of the proline-rich region in A1-type myosin essential light chains: implications for information transmission in the actomyosin complex.
The proline-rich region of A1-type myosin essential light chains functions as a spacer arm separating an actin binding site at the extreme N-terminus from the remainder of the protein. Alteration of the length of this region leaving the actin binding site intact results in altered actin-activated MgATPase kinetics when these light chains are hybridised into myosin subfragment-1. In the case of a mutant in which the length of the proline-rich region was doubled, actin binding by the light chain was uncoupled from kinetic modulation. The implications of this result for information transmission in the actomyosin complex are discussed.
Timson
D J
DJ
School of Biochemistry, The University of Birmingham, Edgbaston, UK.
Trayer
I P
IP
D000199:Actins / Q000502:physiology; D000205:Actomyosin / Q000502:physiology*; D000595:Amino Acid Sequence; D003432:Cross-Linking Reagents; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D018994:Myosin Light Chains / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D011392:Proline / Q000502:physiology*; D055232:Proline-Rich Protein Domains; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics; D013329:Structure-Activity Relationship
D000199:Actins; D003432:Cross-Linking Reagents; D018994:Myosin Light Chains; D010455:Peptides; D011993:Recombinant Fusion Proteins; D000205:Actomyosin; D011392:Proline