大鼠肝脏细胞核维甲酸（RA）受体的精确测定及理化性质

Accurate determination and physicochemical properties of rat liver nuclear retinoic acid (RA) receptors.

作者信息

Brtko J

机构信息

Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava.

出版信息

Biochem Biophys Res Commun. 1994 Oct 28;204(2):439-45. doi: 10.1006/bbrc.1994.2479.

DOI:10.1006/bbrc.1994.2479

PMID:7980499

Abstract

The present study was undertaken to establish a novel in vitro method for quantitative determination of the nuclear RA receptors in rat liver. Binding characteristics of RA receptors (free of any contaminating cytoplasmic proteins), in relation to various physicochemical conditions, were evaluated. Three different binding sites for all-trans RA were found in nuclear proteins of rat liver. One of them represents a high affinity and low capacity RA specific binding site with Ka1 0.687 +/- 0.294 x 10(9) M-1 and the Bmax1 0.644 +/- 0.397 pmol/mg protein. Others represent low affinity and high capacity RA non-specific binding sites with Ka2 2.694 x 10(6) M-1; Bmax2 225 pmol/mg protein and Ka3 0.131 x 10(6) M-1; Bmax3 1125 pmol/mg protein, respectively.

摘要

本研究旨在建立一种用于定量测定大鼠肝脏细胞核视黄酸（RA）受体的新型体外方法。评估了RA受体（不含任何污染的细胞质蛋白）在各种物理化学条件下的结合特性。在大鼠肝脏的核蛋白中发现了全反式视黄酸的三个不同结合位点。其中一个代表高亲和力和低容量的RA特异性结合位点，其解离常数Ka1为0.687±0.294×10⁹ M⁻¹，最大结合容量Bmax1为0.644±0.397 pmol/mg蛋白。其他的分别代表低亲和力和高容量的RA非特异性结合位点，其解离常数Ka2为2.694×10⁶ M⁻¹，最大结合容量Bmax2为225 pmol/mg蛋白；解离常数Ka3为0.131×10⁶ M⁻¹，最大结合容量Bmax3为1125 pmol/mg蛋白。