烟草天蛾脂肪体中脂肪动激素受体的特性

Characterization of the adipokinetic hormone receptor form the fat body of Manduca sexta.

作者信息

Ziegler R, Jasensky R D, Morimoto H

机构信息

Department of Biochemistry, University of Arizona, Tucson 85721, USA.

出版信息

Regul Pept. 1995 Jun 27;57(3):329-38. doi: 10.1016/0167-0115(95)00046-e.

DOI:10.1016/0167-0115(95)00046-e

PMID:7480882

Abstract

A tritium labeled Manduca sexta adipokinetic hormone (M-AKH) was synthesized (pE-L-T-[p3H]F-T-S-S-W-G-NH2) (specific activity 27 Ci/mmol) which was fully active in a bioassay. It was used in a filtration based binding assay to characterize the M-AKH receptor from the fat body of M. sexta. Membrane fractions were prepared from fat body and optimal binding conditions were determined. A Kd of 7.10(-10) M was determined and the receptor concentration estimated to be 0.5 pmol/mg membrane protein. No receptor binding was found when membranes were prepared from brain, heart or flight muscle of M. sexta or from fat body of the cockroach Blaberus discoidalis. However, specific binding was found with membrane preparations from the pterothoracic ganglion of M. sexta. The membranes from the ganglion had a much smaller number of binding sites than the fat body membranes, however, the binding was specific and observed in each experiment.

摘要

合成了一种氚标记的烟草天蛾脂肪动激素（M-AKH）（pE-L-T-[p3H]F-T-S-S-W-G-NH2）（比活度为27 Ci/mmol），其在生物测定中具有完全活性。它被用于基于过滤的结合测定，以表征来自烟草天蛾脂肪体的M-AKH受体。从脂肪体制备膜组分并确定最佳结合条件。测定出解离常数为7.1×10⁻¹⁰ M，受体浓度估计为0.5 pmol/mg膜蛋白。当从烟草天蛾的脑、心脏或飞行肌肉或从蜚蠊的脂肪体制备膜时，未发现受体结合。然而，在来自烟草天蛾翅胸神经节的膜制剂中发现了特异性结合。神经节的膜比脂肪体膜的结合位点数量少得多，然而，这种结合是特异性的，并且在每个实验中都能观察到。