Molecular cloning, expression, and characterization of a Ca2+-dependent nuclease of Arabidopsis thaliana

► The His-AtCaN2 fusion protein was expressed and purified in Escherichia coli. ► The optimal temperature of His-AtCaN2 nuclease activity was 37 °C. ► His-AtCaN2 nuclease activity required a neutral or weakly-alkaline environment. ► His-AtCaN2 nuclease activity was stimulated by Ca2+ and Mg2+. ► His-AtCaN2 nuclease activity was inhibited by Zn2+ and high concentration of Mn2+.