Characterization of a novel alpha 4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus

	Characterization of a novel alpha 4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus
	Peng, C; Chen, WH; Han, YH; Sanders, T; Chew, G; Liu, J; Hawrot, E; Chi, CW; Wang, CG
刊名	ACTA BIOCHIMICA ET BIOPHYSICA SINICA
	2009
卷号	41 期号:10 页码:858-864
关键词	nicotinic acetylcholine receptor subtype alpha 4 4-conotoxin post-translational modification Xenopus oocyte
通讯作者	Chi, CW (reprint author), Tongji Univ, Inst Prot Res, Shanghai 200092, Peoples R China.,zwqi@sibs.ac.cn ; chunguangwang@tongji.edu.cn
英文摘要	As part of continuing studies of the identification of gene organization and cloning of novel alpha-conotoxins, the first alpha 4/4-conotoxin identified in a vermivorous Conus species, designated Qc1.2, was originally obtained by cDNA and genomic DNA cloning from Conus quercinus collected in the South China Sea. The predicted mature toxin of Qc1.2 contains 14 amino acid residues with two disulfide bonds (I-III, II-IV connectivity) in a native globular configuration. The mature peptide of Qc1.2 is supposed to contain an N-terminal post-translationally processed pyroglutamate residue and a free carboxyl C-terminus. This peptide was chemically synthesized and refolded for further characterization of its functional properties. The synthetic Qc1.2 has two interconvertible conformations in aqueous solution, which may be due to the cis-trans isomerization of the two successive Pro residues in its first Cys loop. Using the Xenopus oocyte heterologous expression system, Qc1.2 was shown to selectively inhibit both rat neuronal alpha 3 beta 2 and alpha 3 beta 4 subtypes of nicotinic acetylcholine receptors with low potency. A block of similar to 63% and 37% of the ACh-evoked currents was observed, respectively, and the toxin dissociated rapidly from the receptors. Compared with other characterized alpha-conotoxin members, the unusual structural features in Qc1.2 that confer to its receptor recognition profile are addressed.
学科主题	Biochemistry & Molecular Biology; Biophysics
类目[WOS]	Biochemistry & Molecular Biology ; Biophysics
关键词[WOS]	NICOTINIC ACETYLCHOLINE-RECEPTORS ; ALPHA-CONOTOXIN BUIA ; ANTAGONIST ; PEPTIDE ; BUNGAROTOXIN ; SUBTYPES ; CHANNEL ; CLONING ; EI
收录类别	SCI
语种	英语
WOS记录号	WOS:000270217400008
内容类型	期刊论文
版本	出版稿
源URL	[http://202.127.25.143/handle/331003/1243]
专题	上海生化细胞研究所_上海生科院生化细胞研究所
推荐引用方式 GB/T 7714	Peng, C,Chen, WH,Han, YH,et al. Characterization of a novel alpha 4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus[J]. ACTA BIOCHIMICA ET BIOPHYSICA SINICA,2009,41(10):858-864.
APA	Peng, C.,Chen, WH.,Han, YH.,Sanders, T.,Chew, G.,...&Wang, CG.(2009).Characterization of a novel alpha 4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus.ACTA BIOCHIMICA ET BIOPHYSICA SINICA,41(10),858-864.
MLA	Peng, C,et al."Characterization of a novel alpha 4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus".ACTA BIOCHIMICA ET BIOPHYSICA SINICA 41.10(2009):858-864.