Mulugu Sashidhar, Bai Wenli, Fridy Peter C, Bastidas Robert J, Otto James C, Dollins D Eric, Haystead Timothy A, Ribeiro Anthony A, York John D
Howard Hughes Medical Institute, Department of Pharmacology and Cancer Biology, Duke University Medical Center, DUMC 3813, Durham, NC 27710, USA.
Science. 2007 Apr 6;316(5821):106-9. doi: 10.1126/science.1139099.
Inositol pyrophosphates are a diverse group of high-energy signaling molecules whose cellular roles remain an active area of study. We report a previously uncharacterized class of inositol pyrophosphate synthase and find it is identical to yeast Vip1 and Asp1 proteins, regulators of actin-related protein-2/3 (ARP 2/3) complexes. Vip1 and Asp1 acted as enzymes that encode inositol hexakisphosphate (IP6) and inositol heptakisphosphate (IP7) kinase activities. Alterations in kinase activity led to defects in cell growth, morphology, and interactions with ARP complex members. The functionality of Asp1 and Vip1 may provide cells with increased signaling capacity through metabolism of IP6.
肌醇焦磷酸是一类多样的高能信号分子，其细胞功能仍是一个活跃的研究领域。我们报道了一类以前未被表征的肌醇焦磷酸合酶，并发现它与酵母Vip1和Asp1蛋白相同，后者是肌动蛋白相关蛋白2/3（ARP 2/3）复合物的调节因子。Vip1和Asp1作为编码肌醇六磷酸（IP6）和肌醇七磷酸（IP7）激酶活性的酶发挥作用。激酶活性的改变导致细胞生长、形态以及与ARP复合物成员相互作用方面的缺陷。Asp1和Vip1的功能可能通过IP6的代谢为细胞提供增强的信号传导能力。
