Jans D A, Hemmings B A
FEBS Lett. 1986 Sep 1;205(1):127-31. doi: 10.1016/0014-5793(86)80879-1.
Mutants of the pig kidney cell line, LLC-PK1, affected in cAMP metabolism, were examined for cAMP-dependent protein kinase (cAMP-PK) activity and for cAMP-mediated induction of urokinase-type plasminogen activator (uPA). The FIB4 and FIB6 mutant cell lines possessed about 10% parental levels of cAMP-PK activity and concomitantly reduced uPA production (10-20% parental) in response to calcitonin, forskolin and 8-bromo cAMP. The FIB1, FIB2 and FIB5 mutant cell lines had about 70% parental levels of cAMP-PK and the synthesis of uPA was 40-60% parental. Thus, cAMP-mediated induction of uPA showed a dependence on the absolute levels of cAMP-PK. However, uPA synthesis in response to phorbol-12-myristate-13-acetate by all of the mutants was similar to parental, which indicates that enzyme induction mediated by phorbol esters does not involve cAMP or cAMP-PK.
对猪肾细胞系LLC-PK1中受cAMP代谢影响的突变体进行了cAMP依赖性蛋白激酶（cAMP-PK）活性检测以及cAMP介导的尿激酶型纤溶酶原激活剂（uPA）诱导检测。FIB4和FIB6突变细胞系的cAMP-PK活性约为亲本水平的10%，并且响应降钙素、福斯可林和8-溴cAMP时uPA产量相应降低（为亲本的10%-20%）。FIB1、FIB2和FIB5突变细胞系的cAMP-PK水平约为亲本水平的70%，uPA合成量为亲本的40%-60%。因此，cAMP介导的uPA诱导表现出对cAMP-PK绝对水平的依赖性。然而，所有突变体对佛波醇-12-肉豆蔻酸酯-13-乙酸酯的uPA合成与亲本相似，这表明佛波醇酯介导的酶诱导不涉及cAMP或cAMP-PK。
