Abstract:
Amino-terminal acetylation is catalyzed by a set of N-terminal acetyltransferases (NATs). The NatA complex (including X-linked Naa10 and Naa15) is the major acetyltransferase, with 40-50% of all mammalian proteins being potential substrates. However, the overall role of amino-terminal acetylation on a whole-organism level is poorly understood, particularly in mammals. Male mice lacking Naa10 show no globally apparent in vivo amino-terminal acetylation impairment and do not exhibit complete embryonic lethality. Rather Naa10 nulls display increased neonatal lethality, and the majority of surviving undersized mutants exhibit a combination of hydrocephaly, cardiac defects, homeotic anterior transformation, piebaldism, and urogenital anomalies. Naa12 is a previously unannotated Naa10-like paralog with NAT activity that genetically compensates for Naa10. Mice deficient for Naa12 have no apparent phenotype, whereas mice deficient for Naa10 and Naa12 display embryonic lethality. The discovery of Naa12 adds to the currently known machinery involved in amino-terminal acetylation in mice.
摘要:
氨基末端乙酰化由一组N-末端乙酰转移酶(NAT)催化。NatA复合物(包括X连接的Naa10和Naa15)是主要的乙酰转移酶,所有哺乳动物蛋白质中有40-50%是潜在的底物。然而,氨基末端乙酰化在整个生物体水平上的总体作用知之甚少,特别是在哺乳动物中。缺乏Naa10的雄性小鼠在体内没有显示出明显的氨基末端乙酰化损害,也没有显示出完全的胚胎致死性。相反,Naa10空位显示新生儿致死率增加,大多数幸存的矮小突变体表现出脑积水,心脏缺陷,同源前变性,piebaldism,和泌尿生殖器异常.Naa12是以前未注释的Naa10类同系物,具有NAT活性,可在遗传上补偿Naa10。缺乏Naa12的小鼠没有明显的表型,而缺乏Naa10和Naa12的小鼠表现出胚胎致死性。Naa12的发现增加了目前已知的参与小鼠氨基末端乙酰化的机制。