NMR Assignment and Secondary Structure of Coiled Coil Domain of C-terminal Myosin Binding Subunit of Myosin Phosphatase

作者：Sharma Alok K^*; Rigby Alan C

来源：Protein and Peptide Letters, 2014, 21(7): 639-645.

DOI：10.2174/0929866521666140328112426

• 2D H-1-N-15 HSQC
• Coiled coil MBS
• Leucine zipper PKG-I alpha(1-59)
• MLCP
• NMR assignment
• Secondary structure
• VSMC

Protein-protein interactions between the C-terminal domain of Myosin Binding Subunit (MBS) of MLC Phosphatase (MBSCT180; C-terminal 180 aa) and the N-terminal coiled coil (CC) leucine zipper (LZ) domain of PKGI, PKG 1 59 play an important role in the process of Smooth Muscle Cell relaxation. The paucity of three-dimensional structural information for MBSCT180 prevents an atomic level understanding of the MBS-PKG contractile complex. MBSCT180 is comprised of three structurally different sub-domains including a non- canonical CC, a CC, and a LZ. Recently we reported polypeptide purification and biophysical characterization of the CC domain and the LZ domain of MBSCT180 (Sharma et al, Prot Expr Purif 2012). Here we report H-1, C-13, N-15 chemical shift assignments of homodimeric CC MBS domain encompassing amino acid residues Asp931-Leu980 using 2D and 3D heteronuclear NMR spectroscopy. Secondary structure analyses deduced from these NMR chemical shift data have identified a contiguous stretch of 36 residues from Phe932 to Ala967 that is involved in the formation of coiled coil alpha-helical region within CC MBS domain. The N-terminal residue Asp931 and the C-terminally positioned residues Thr968-Ala975, Arg977, and Ser978 adopt nonhelical loop conformations.

• 出版日期2014