PRKACA（protein kinase cAMP-activated catalytic subunit alpha），癌症关联基因，基因ID：5566，该基因编码蛋白激酶A的一个催化亚单位，作为一种具有两个调节亚单位和两个催化亚单位的四聚体全酶以非活性形式存在。cAMP使非活性全酶解离成一个调节亚单位二聚体，与四个cAMP和两个自由单体催化亚单位结合。人类已鉴定出四种不同的调节亚单位和三种催化亚单位。蛋白激酶A的cAMP依赖性磷酸化对许多细胞过程，包括分化、增殖和凋亡都很重要。由体细胞突变或包括该基因的区域的基因组重复引起的该基因的组成性激活与肾上腺皮质增生和腺瘤有关，并与促肾上腺皮质激素依赖性库欣综合征有关。选择性剪接导致编码不同亚型的多个转录变体。已经描述了在N端不同的组织特异性亚型，并且这些亚型可能在一些亚型的N端发生的翻译后修饰中有所不同。This gene encodes one of the catalytic subunits of protein kinase A， which exists as a tetrameric holoenzyme with two regulatory subunits and two catalytic subunits， in its inactive form. cAMP causes the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to four cAMP and two free monomeric catalytic subunits. Four different regulatory subunits and three catalytic subunits have been identified in humans. cAMP-dependent phosphorylation of proteins by protein kinase A is important to many cellular processes， including differentiation。