Protein kinase A (PKA), one of the most widely studied protein kinases, has many functions in cells, including regulating the metabolism of sugar and lipid. Here we identified nine isoforms of the PKA family in grass carp Ctenopharyngodon idella and obtained their complete coding sequences (CDS), including PRKACAa, PRKACAb, PRKACBa, PRKACBb, PRKAR1A, PRKAR1B, PRKAR2Aa, PRKAR2Ab and PRKAR2B, and PRKACA, PRKACB and PRKAR2A, which may experience fish-specific genome duplication. Sequence analysis showed that the predicted protein structures of PKA gene family members in grass carp were different. Grass carp PRKACAa, PRKACAb, PRKACBa, and PRKACBb contained serine/threonine protein kinases, while PRKAR1A, PRKAR1B, PRKAR2Aa, PRKAR2Ab and PRKAR2B contained two cyclic nucleotide-monophosphate binding domains. PRKACAa, PRKACBa, PRKACBb, PRKAR1A, PRKAR1B and PRKAR2Aa contained 10 coding exons, while PRKACAb and PRKAR2Ab consisted of 12 coding exons and 5 coding exons, respectively. The messenger RNA (mRNA) of the nine PKA isoforms was detected in a wide range of tissues, but their abundance showed tissue-dependent expression patterns. In tunicamycin-induced adipocyte lipolysis, only the mRNA levels of PRKACAb and PRKACBa showed a significant increase in adipocyte (p < .05), indicating that nine PKA isoforms may serve somewhat different roles in endoplasmic reticulum (ER) stress-mediated lipolysis in fish. These results suggested that nine grass carp PKA isoforms may play different roles in tissues, and their expression levels were differently modulated by ER stress in adipocyte.

蛋白激酶A（PKA）是研究最广泛的蛋白激酶之一，在细胞中具有许多功能，包括调节糖和脂质的代谢。在这里，我们确定的九个亚型PKA家庭草鱼草鱼，取得他们的完整的编码序列（CDS），包括PRKACAa，PRKACAb，PRKACBa，PRKACBb，PRKAR1A，PRKAR1B，PRKAR2Aa，PRKAR2Ab和PRKAR2B，和PRKACA，PRKACB和PRKAR2A，可能会遇到鱼类特有的基因组重复。序列分析表明，预测的PKA蛋白结构草鱼的基因家族成员不同。草鱼PRKACAa，PRKACAb，PRKACBa和PRKACBb包含丝氨酸/苏氨酸蛋白激酶，而PRKAR1A，PRKAR1B，PRKAR2Aa，PRKAR2Ab和PRKAR2B包含两个环状核苷酸-单磷酸结合域。PRKACAa，PRKACBa，PRKACBb，PRKAR1A，PRKAR1B和PRKAR2Aa包含10个编码外显子，而PRKACAb和PRKAR2Ab分别由12个编码外显子和5个编码外显子组成。在广泛的组织中检测到了九种PKA亚型的信使RNA（mRNA），但它们的丰度显示出组织依赖性的表达模式。在衣霉素诱导的脂肪细胞脂解中，仅PRKACAb和PRKACB的mRNA水平a显示脂肪细胞显着增加（p  <.05），表明9种PKA亚型可能在鱼类内质网（ER）应激介导的脂解中发挥了不同的作用。这些结果表明9种草鱼PKA同工型在组织中可能发挥不同的作用，并且它们的表达水平受到脂肪细胞中ER胁迫的不同调节。