The structural determinations of the leucine zipper coiled-coil domains of the cGMP-dependent protein kinase Iα and its interaction with the myosin binding subunit of the myosin light chains phosphase

Physiologic relaxation of vascular smooth muscle is induced by the cyclic guanosine monophosphate (cgmp)- dependent protein kinase iα enzyme (cgkiα),which activates myosin phosphatase (mlcp). this activation process is thought to occur through the interaction involving both n- and c-terminal leucine zipper coiled-coil (lzcc) domains of the kinase enzyme (cgkiα) with the myosin binding subunit (mbs) of mlcp. in this review,i summarize how to define the lzcc domains in both n-terminal cgkiα 1-59and c-terminal mbs proteins using predictive and experimental methods,how to make a rapid and accurate structure determination of a cgkiα 1-59 molecule using nmr's residual dipolar coupling (rdc) measurements,and how to indentify the existence of a weak protein interaction between n-terminal lzcc domain (cgkiα 1-59) and a lzcc domain (mbsct42) within the c-terminal mbs. in addition,the location and orientation of the residues in lzcc proteins can be readily visualized using a novel diagram,the so-called wenxiang diagram