| Structural highlights
Disease
[CALM2_HUMAN] Catecholaminergic polymorphic ventricular tachycardia;Brugada syndrome;Romano-Ward syndrome. The disease is caused by mutations affecting the gene represented in this entry. Mutations in CALM2 are the cause of LQT15.
Function
[CALM2_HUMAN] Calmodulin mediates the control of a large number of enzymes, ion channels, aquaporins and other proteins through calcium-binding. Among the enzymes to be stimulated by the calmodulin-calcium complex are a number of protein kinases and phosphatases. Together with CCP110 and centrin, is involved in a genetic pathway that regulates the centrosome cycle and progression through cytokinesis (PubMed:16760425). Mediates calcium-dependent inactivation of CACNA1C (PubMed:26969752). Positively regulates calcium-activated potassium channel activity of KCNN2 (PubMed:27165696).[1] [2] [3]
Publication Abstract from PubMed
The family of bacterial SidE enzymes catalyses phosphoribosyl-linked (PR) serine ubiquitination and promotes infectivity of Legionella pneumophilia, a pathogenic bacterium causing Legionnaires' disease(1-3). SidEs share the genetic locus with the Legionella effector SidJ that spatiotemporally opposes their toxicity in yeast and mammalian cells, through an unknown mechanism(4-6). Deletion of SidJ leads to a significant defect in the growth of Legionella in both its natural host amoeba and in murine macrophages(4,5). Here, we demonstrate that SidJ is a glutamylase that modifies the catalytic glutamate in the mono-ADPribosyl transferase (mART) domain of SdeA thus blocking its ubiquitin (Ub) ligase activity. SidJ glutamylation activity requires interaction with calmodulin (CaM), a eukaryotic specific co-factor, and can be regulated by intracellular changes in Ca(2+) concentrations. The cryo-EM structure of SidJ/human apo-CaM complex revealed the architecture of this unique heterodimeric glutamylase. In infected cells, we show that SidJ mediates glutamylation of SidEs on the surface of Legionella-containing vacuoles (LCVs). Using quantitative proteomics, we also uncovered multiple host proteins as putative targets of SidJ-mediated glutamylation. Collectively, this study reveals the mechanism of SidE ligases inhibition by a SidJ/CaM glutamylase and opens new avenues for studying protein glutamylation, an understudied protein modification in higher eukaryotes.
Inhibition of bacterial ubiquitin ligases by SidJ-calmodulin-catalysed glutamylation.,Bhogaraju S, Bonn F, Mukherjee R, Adams M, Pfleiderer MM, Galej WP, Matkovic V, Lopez-Mosqueda J, Kalayil S, Shin D, Dikic I Nature. 2019 Jul 22. pii: 10.1038/s41586-019-1440-8. doi:, 10.1038/s41586-019-1440-8. PMID:31330532[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Tsang WY, Spektor A, Luciano DJ, Indjeian VB, Chen Z, Salisbury JL, Sanchez I, Dynlacht BD. CP110 cooperates with two calcium-binding proteins to regulate cytokinesis and genome stability. Mol Biol Cell. 2006 Aug;17(8):3423-34. Epub 2006 Jun 7. PMID:16760425 doi:10.1091/mbc.E06-04-0371
- ↑ Boczek NJ, Gomez-Hurtado N, Ye D, Calvert ML, Tester DJ, Kryshtal D, Hwang HS, Johnson CN, Chazin WJ, Loporcaro CG, Shah M, Papez AL, Lau YR, Kanter R, Knollmann BC, Ackerman MJ. Spectrum and Prevalence of CALM1-, CALM2-, and CALM3-Encoded Calmodulin Variants in Long QT Syndrome and Functional Characterization of a Novel Long QT Syndrome-Associated Calmodulin Missense Variant, E141G. Circ Cardiovasc Genet. 2016 Apr;9(2):136-146. doi:, 10.1161/CIRCGENETICS.115.001323. Epub 2016 Mar 11. PMID:26969752 doi:http://dx.doi.org/10.1161/CIRCGENETICS.115.001323
- ↑ Yu CC, Ko JS, Ai T, Tsai WC, Chen Z, Rubart M, Vatta M, Everett TH 4th, George AL Jr, Chen PS. Arrhythmogenic calmodulin mutations impede activation of small-conductance calcium-activated potassium current. Heart Rhythm. 2016 Aug;13(8):1716-23. doi: 10.1016/j.hrthm.2016.05.009. Epub 2016, May 7. PMID:27165696 doi:http://dx.doi.org/10.1016/j.hrthm.2016.05.009
- ↑ Bhogaraju S, Bonn F, Mukherjee R, Adams M, Pfleiderer MM, Galej WP, Matkovic V, Lopez-Mosqueda J, Kalayil S, Shin D, Dikic I. Inhibition of bacterial ubiquitin ligases by SidJ-calmodulin-catalysed glutamylation. Nature. 2019 Jul 22. pii: 10.1038/s41586-019-1440-8. doi:, 10.1038/s41586-019-1440-8. PMID:31330532 doi:http://dx.doi.org/10.1038/s41586-019-1440-8
|