Unknown

Dataset Information

0

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.


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.

SUBMITTER: Ishida H 

PROVIDER: S-EPMC2788880 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

altmetric image

Publications

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.

Ishida Hiroaki H   Rainaldi Mario M   Vogel Hans J HJ  

The Journal of biological chemistry 20090810 41


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  ...[more]

Similar Datasets

| S-EPMC3522297 | biostudies-literature
| S-EPMC2661409 | biostudies-literature
| S-EPMC1920248 | biostudies-literature
| S-EPMC6151454 | biostudies-literature
| S-EPMC3961691 | biostudies-literature
| S-EPMC2866273 | biostudies-literature
| S-EPMC2680277 | biostudies-literature
| S-EPMC6402808 | biostudies-literature
| S-EPMC1914108 | biostudies-literature
| S-EPMC1599897 | biostudies-literature