Regulation of cAMP-dependent protein kinases: the human protein kinase X (PrKX) reveals the role of the catalytic subunit alphaH-alphaI loop. by Diskar, M, Zenn, H, Kaupisch, A, Kaufholz, M, Brockmeyer, S, Sohmen, D, Berrera, M, Zaccolo, M, Boshart, M, Herberg, F, Prinz, A