2N77

NMR solution structure of a complex of PEP-19 bound to the C-domain of apo calmodulin

Summary for 2N77

• Entry DOI: 10.2210/pdb2n77/pdb
• NMR Information: BMRB: 25796
• Descriptor: Calmodulin, Purkinje cell protein 4 (2 entities in total)
• Functional Keywords: intrinsically disordered, structural transition, signaling protein
• Biological source: Homo sapiens (human); More
• Cellular location: Cytoplasm, cytoskeleton, spindle : P62158
• Total number of polymer chains: 2
• Total formula weight: 15202.63

Authors

Wang, X.,Putkey, J.A. (deposition date: 2015-09-04, release date: 2016-11-30, Last modification date: 2024-05-15)

Primary citation

Wang, X.,Putkey, J.A.
PEP-19 modulates calcium binding to calmodulin by electrostatic steering.
Nat Commun, 7:13583-13583, 2016

PubMed Abstract: PEP-19 is a small protein that increases the rates of Ca binding to the C-domain of calmodulin (CaM) by an unknown mechanism. Although an IQ motif promotes binding to CaM, an acidic sequence in PEP-19 is required to modulate Ca binding and to sensitize HeLa cells to ATP-induced Ca release. Here, we report the NMR solution structure of a complex between PEP-19 and the C-domain of apo CaM. The acidic sequence of PEP-19 associates between helices E and F of CaM via hydrophobic interactions. This allows the acidic side chains in PEP-19 to extend toward the solvent and form a negatively charged surface that resembles a catcher's mitt near Ca binding loop III of CaM. The topology and gradients of negative electrostatic surface potential support a mechanism by which PEP-19 increases the rate of Ca binding to the C-domain of CaM by 'catching' and electrostatically steering Ca to site III.

PubMed: 27876793
DOI: 10.1038/ncomms13583

Experimental method

SOLUTION NMR