Oppert B, Takemoto D J
Department of Biochemistry, Kansas State University, Manhattan 66506.
Biochem Biophys Res Commun. 1991 Jul 31;178(2):474-9. doi: 10.1016/0006-291x(91)90131-p.
Using synthetic peptides, the identification of the retinal cyclic-GMP phosphodiesterase (cGMP PDE) interaction sites for the inhibitory gamma-subunit in the catalytic alpha-subunit were recently localized to residues #16-30 and 78-90 in the alpha-subunit (1). In this study, a binding radioimmunoassay (RIA) showed a weak interaction between PDE gamma and PDE beta subunits in PDE beta residues #15-34, and stronger interaction sites were found in residues #91-110 and 211-230. Sequence comparison between PDE alpha and PDE beta illustrate some differences in these regions, particularly in PDE alpha 16-30 and PDE beta 15-34 regions. Differences in interaction sites in PDE alpha and PDE beta for PDE gamma may account for the differences in affinities observed between PDE gamma and the catalytic subunits.
利用合成肽，近期已将催化性α亚基中抑制性γ亚基与视网膜环磷酸鸟苷磷酸二酯酶（cGMP PDE）的相互作用位点定位至α亚基中的16 - 30号残基和78 - 90号残基（1）。在本研究中，一项结合放射免疫分析（RIA）显示，PDEγ与PDEβ亚基在PDEβ的15 - 34号残基间存在弱相互作用，且在91 - 110号残基和211 - 230号残基中发现了更强的相互作用位点。PDEα与PDEβ之间的序列比较表明这些区域存在一些差异，尤其是在PDEα的16 - 30区域和PDEβ的15 - 34区域。PDEγ与PDEα和PDEβ相互作用位点的差异可能解释了PDEγ与催化亚基之间观察到的亲和力差异。
