Activation of protein kinase A alters subnuclear distribution pattern of human steroidogenic factor 1 in living cells

作     者：刘伟 范吴强 Toshihiko Yanase Masayuki Saitoh 吴茵 

作者机构：Department of Medicine and Endocrinology Department of Medicine and Bioregulatory Science Department of Geriatric Medicine 

出 版 物：《Chinese Medical Journal》 (中华医学杂志（英文版）)

年 卷 期：2004年第117卷第7期

页      面：1017-1022页

核心收录：

学科分类：1002[医学-临床医学] 1001[医学-基础医学(可授医学、理学学位)] 10[医学] 

主　　题：steroidogenic factor 1· protein kinase A· green fluorescent protein 

摘      要：Background The aim of this study was to identify the subnuclear distribution pattern of human orphan nuclear receptor steroidogenic factor 1 (SF-1) in living cells with and without the activation of protein kinase A (PKA) signal pathway, and thus try to explain the unknown mechanism by which PKA potentiates SF-1 transactivation. Methods Full-length cDNAs of wild type and a naturally occurring mutant (G35E) human SF-1 were cloned and fused with green fluorescent protein (GFP). Subcellular distribution pattern of human SF-1 in living cells, whose PKA signaling was either activated or not, was studied by laser confocal microscopy after the validity of the gene sequence was *** The transactivation ability of the GFP-SF-1 chimeric protein was highly conserved. Wild type human SF-1 diffused homogeneously within the nuclei of cells when PKA was not active, and converged to clear foci when PKA was activated. Mutant SF-1 diffused within the nuclei even in the presence of PKA activation, surprisingly aggregating as fluorescent dots inside the nucleoli, a phenomenon not altered by *** Activation of PKA causes wild type, but not mutant SF-1 to alter its subnuclear distribution pattern to a transactivationally active form (foci formation). This finding may throw new light on the mechanism by which PKA activates the orphan nuclear receptor.