Department of Biological Chemistry and CNR Institute of Neurosciences, University of Padova, viale G. Colombo 3, 35131 Padova, Italy.
Biochem J. 2010 Jan 27;426(1):19-29. doi: 10.1042/BJ20090813.
Cystic fibrosis mostly follows a single Phe508 deletion in CFTR (cystic fibrosis transmembrane regulator) (CFTRDeltaF508), thereby causing premature fragmentation of the nascent protein with concomitant alterations of diverse cellular functions. We show that CK2, the most pleiotropic protein kinase, undergoes allosteric control of its different cellular forms in the presence of short CFTR peptides encompassing the Phe508 deletion: these CFTRDeltaF508 peptides drastically inhibit the isolated catalytic subunit (alpha) of the kinase and yet up-regulate the holoenzyme, composed of two catalytic and two non-catalytic (beta) subunits. Remarkable agreement between in silico docking and our biochemical data point to different sites for the CFTRDeltaF508 peptide binding on isolated CK2alpha and on CK2beta assembled into the holoenzyme, suggesting that CK2 targeting may be perturbed in cells expressing CFTRDeltaF508; this could shed light on some pleiotropic aspects of cystic fibrosis disease.
囊性纤维化主要是由 CFTR(囊性纤维化跨膜转导调节因子)中的单个 Phe508 缺失引起的,从而导致新生蛋白的过早片段化,并伴有多种细胞功能的改变。我们表明,CK2 是最具多功能性的蛋白激酶,在存在包含 Phe508 缺失的短 CFTR 肽的情况下,其不同细胞形式会经历别构控制:这些 CFTRDeltaF508 肽会严重抑制激酶的分离催化亚基(α),但却上调了由两个催化亚基和两个非催化亚基(β)组成的全酶。计算机对接和我们的生化数据之间的惊人一致性表明,CFTRDeltaF508 肽在分离的 CK2alpha 和组装成全酶的 CK2beta 上的结合具有不同的结合位点,这表明在表达 CFTRDeltaF508 的细胞中 CK2 的靶向可能会受到干扰;这可能会揭示囊性纤维化疾病的一些多效性方面。