Acetylation stabilises calmodulin-regulated calcium signalling

Calmodulin is a conserved calcium signalling protein that regulates a wide range of cellular functions. Amino-terminal acetylation is a ubiquitous posttranslational modification that affects ~ 90% of all human proteins, to stabilise structure, as well as regulate function and proteolytic degradation. Here we present data on the impact of amino-terminal acetylation upon structure and calcium signalling function of fission yeast calmodulin. We show NatA dependent acetylation stabilises the helical structure of the S. pombe calmodulin, impacting its ability to associate with myosin at endocytic foci. We go on to show this conserved modification impacts both the calcium binding capacity of yeast and human calmodulins. These findings have significant implications for research undertaken into this highly conserved essential protein.