Structure of the mouse glucocorticoid receptor: rapid analysis by size-exclusion high-performance liquid chromatography.
Structure of the mouse glucocorticoid receptor: rapid analysis by size-exclusion high-performance liquid chromatography.
复制标题
小鼠糖皮质激素受体的结构:通过尺寸排阻高效液相色谱进行快速分析。
DOI:
10.1021/bi00356a038
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发表时间:
1986
期刊:
影响因子:
2.9
通讯作者:
Vedeckis,WV
中科院分区:
文献类型:
--
作者:
LaPointe,MC;Chang,CH;Vedeckis,WV
Department of Biochemistry and Molecular Biology, Louisiana State University Medical Center, New Orleans, Louisiana 70112 Received October 7, Ą985; Revised Manuscript Received December 2, 1985 abstract: Gel-exclusion high-performanceliquid chromatography (HPLC) has been used to separate the untransformed from the transformed glucocorticoid receptor (GC-R) extracted from mouse AtT-20 cells. With 200 mM potassium phosphate as the eluent, an efficient separation of the forms of the GC-R is attained in 15-20 min. The untransformed cytosolicGC-R elutes from the columnwith a Stokes radius {Rs) of 8.2-8.6 nm, as do the molybdate-stabilized GC-R, the purified untransformed GC-R, and the cross-linked cytosolic GC-R. GC-R transformed in vitro by either ammonium sulfate precipitation, KC1 treatment, or G-25 chromatography elutes with an Rs of 5.7-6 nm. Also, GC-R extracted from the nucleus with either 0.3 Mkc1 or 2 mM sodium tungstate, or purified by two cycles of DNA-cellulose chromatography, has an Rs of 5.5-6.3 nm. The data are identical either in the presence or in the absence of 20 mM Na2Mo04, suggesting that molybdate is not causing aggregation to produce a larger Rs value than that of the native receptor. Vertical tube rotor sucrose gradient ultracentrifugation of cytosol produces three forms of the GC-R: 9.1 S, 5.2 S, and 3.8 S. Sequential analysis of the GC-R formsby HPLC and vertical tube rotor ultracentrifugation and vice versa allows for the hydrodynamic determination of molecular weight within a very short time period (2-3 h total). The untransformed 9. IS species of GC-R pooled from Mo042™-containing sucrose gradients has an Rs of 8.6 nm (Mr 310K-340K) while both the 5.2 S and 3.8 S forms have an Rs of 6 nm (Mr 115K-140K and 96K-100K, respectively). Conversely, if the 6-nm form of the receptor, generated either by KC1 treatment or by G-25 chromatography, is pooled from HPLC, then it subsequently sediments on Mo042"-containing gradients as a 3.5-4.6 S species. This probably indicates that the 5.2 S transformed GC-R is unstable and dissociates into its constituents during HPLC, despite the rapidity of the process. From the calculated molecular weight for each of the three GC-R forms, it is suggested that the untransformed oligomeric GC-R dissociates into monomeric subunits during transformation and that the intermediate form is not a dimer of identical monomeric subunits.(jTlucocorticoids are physiological regulators which interact with specific receptor proteins in responsive cells (Yamamoto & Alberts, 1976). After the hormone binds to the receptor, the glucocorticoid receptor (GC-R) 1 complex is transformed to a DNA-binding moiety. The transformed receptor interacts with acceptor sites on the DNA to affect specific gene tran-scription.