Study of identification and characterization of crustacean hyperglycemic hormone receptor: ligand activation, binding, and specificityof receptor guanylyl cyclases / 甲殼類升血糖荷爾蒙受體之確認與特性研究:受體型鳥苷酸環化酶之配體活化、結合與特異度

碩士 / 國立彰化師範大學 / 生物學系 / 100 / In the purpose, analysis of 2 mGC genes, PcGC-M2 and PcGC-M2B, were cloned from the muscle of the crayfish in our previous studies and evaluated for their binding affinities of polymorphic CHH peptides to PcGC-M2 and PcGC-M2B are compared. The 2 mGC proteins are identical in containing the same extracellular binding and transmembrane domains, while PcGC-M2 also contains a kinase homology domain
and a cyclase catalytic domain and PcGC-M2B only a truncated kinase homology domain. Immunohistochemical localization of PcGC-M2 in membrane of abdominal
muscle in Procambarus clarkii. The results of semi-quantitative PCR showed the transcript levels that expressed as a ratio of PcGC-M2 to PcGC-M2B, significantly
increased after eyestalk ablation in CHH target tissues, muscle and hepatopancreas. When expressed in human embryonic kidney-293T cells, PcGC-M2 and PcGC-M2B
are cell-surface glycoproteins and capable of forming a PcGC-M2/PcGC-M2B heterodimer. In the GC activity, CHH is able to stimulate the GC activity of PcGC-M2 in a dose-dependent manner. The activity of PcGC-M2 was decreased
when co-expressed with PcGC-M2B, which by itself lacks GC activity. In CHH binding assay, CHH is able to bind to PcGC-M2, PcGC-M2B, or PcGC-M2/PcGC-M2B. Through the results of the displacement assay indicated D-Phe3 CHH has higher affinity than L-Phe3 CHH or CHH-L to PcGC-M2.
According to the results, the PcGC-M2 and PcGC-M2B, in either homodimeric or heterodimeric form, are CHH receptors. The effects of regulating mechanism of CHH
on physiological events, that depended on different affinities of CHH family to receptor and that sensitivity of CHH target tissues to CHH regulation varies as a
function of the ratio of levels of PcGC-M2 to PcGC-M2B.

Identiferoai:union.ndltd.org:TW/100NCUE5112033
Date January 2012
CreatorsShao-Yen Huang, 黃劭彥
ContributorsChi-Ying Lee, Ruey-Bing Yang, 李奇英, 楊瑞彬
Source SetsNational Digital Library of Theses and Dissertations in Taiwan
Languagezh-TW
Detected LanguageEnglish
Type學位論文 ; thesis
Format103

Page generated in 0.014 seconds