2KN2
Solution structure of the C-terminal domain of soybean calmodulin isoform 4 fused with the calmodulin-binding domain of NtMKP1
Summary for 2KN2
| Entry DOI | 10.2210/pdb2kn2/pdb |
| Descriptor | Calmodulin, CALCIUM ION (2 entities in total) |
| Functional Keywords | calmodulin, calmodulin-target complex, soybean calmodulin, scam4, mapk phosphatase 1, ntmkp1, tobacco mkp1, metal binding protein |
| Biological source | Glycine max (soybeans) |
| Total number of polymer chains | 1 |
| Total formula weight | 10527.77 |
| Authors | Ishida, H.,Rainaldi, M.,Vogel, H.J. (deposition date: 2009-08-12, release date: 2009-08-25, Last modification date: 2024-05-22) |
| Primary citation | Ishida, H.,Rainaldi, M.,Vogel, H.J. Structural studies of soybean calmodulin isoform 4 bound to the calmodulin-binding domain of tobacco mitogen-activated protein kinase phosphatase-1 provide insights into a sequential target binding mode. J.Biol.Chem., 284:28292-28305, 2009 Cited by PubMed Abstract: The calcium regulatory protein calmodulin (CaM) binds in a calcium-dependent manner to numerous target proteins. The calmodulin-binding domain (CaMBD) region of Nicotiana tabacum MAPK phosphatase has an amino acid sequence that does not resemble the CaMBD of any other known Ca(2+)-CaM-binding proteins. Using a unique fusion protein strategy, we have been able to obtain a high resolution solution structure of the complex of soybean Ca(2+)-CaM4 (SCaM4) and this CaMBD. Complete isotope labeling of both parts of the complex in the fusion protein greatly facilitated the structure determination by NMR. The 12-residue CaMBD region was found to bind exclusively to the C-lobe of SCaM4. A specific Trp and Leu side chain are utilized to facilitate strong binding through a novel "double anchor" motif. Moreover, the orientation of the helical peptide on the surface of Ca(2+)-SCaM4 is distinct from other known complexes. The N-lobe of Ca(2+)-SCaM4 in the complex remains free for additional interactions and could possibly act as a calcium-dependent adapter protein. Signaling through the MAPK pathway and increases in intracellular Ca(2+) are both hallmarks of the plant stress response, and our data support the notion that coordination of these responses may occur through the formation of a unique CaM-MAPK phosphatase multiprotein complex. PubMed: 19667066DOI: 10.1074/jbc.M109.025080 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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