Department of Biology, University of Milano, Milano, Italy.
FEBS Lett. 2010 Dec 1;584(23):4783-8. doi: 10.1016/j.febslet.2010.11.008. Epub 2010 Nov 10.
Plant auto-inhibited Ca(2+)-ATPase 8 (ACA8) and animal plasma membrane Ca(2+)-ATPase 4b (PMCA4b) are representatives of plant and animal 2B P-type ATPases with a regulatory auto-inhibitory domain localized at the N- and C-terminus, respectively. To check whether the regulatory domain works independently of its terminal localization and if auto-inhibitory domains of different organisms are interchangeable, a mutant in which the N-terminus of ACA8 is repositioned at the C-terminus and chimeras in which PMCA4b C-terminus is fused to the N- or C-terminus of ACA8 were analysed in the yeast mutant K616 devoid of endogenous Ca(2+)-ATPases. Results show that the regulatory function of the terminal domain is independent from its position in ACA8 and that the regulatory domain belonging to PMCA4b is able to at least partially auto-inhibit ACA8.
植物自动抑制型 Ca(2+)-ATP 酶 8（ACA8）和动物质膜 Ca(2+)-ATP 酶 4b（PMCA4b）分别是植物和动物 2B P 型 ATP 酶的代表，它们都具有位于 N 端和 C 端的调节性自动抑制结构域。为了检查调节结构域是否可以独立于其末端定位起作用，以及不同生物体的自动抑制结构域是否可以互换，我们分析了酵母突变体 K616 中 ACA8 的 N 端重新定位到 C 端的突变体，以及 PMCA4b 的 C 端融合到 ACA8 的 N 端或 C 端的嵌合体。结果表明，末端结构域的调节功能与其在 ACA8 中的位置无关，并且属于 PMCA4b 的调节结构域至少可以部分地自动抑制 ACA8。
