Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: dentification of the prokaryotic ligand-gated ion channels and their implications for the mechanisms and origins of animal Cys-loop ion channels. | Research Open Access Identification of the prokaryotic ligand-gated ion channels and their implications for the mechanisms and origins of animal Cys-loop ion channels Asba Tasneem Lakshminarayan M Iyer Eric Jakobsson and L Aravind Addresses Beckman Institute University of Illinois at Urbana-Champaign 405 N Mathews Avenue Urbana IL 61801 USA. National Center for Biotechnology Information National Library of Medicine National Institutes of Health Bethesda MD 20894 USA. Correspondence LAravind. E-mail aravind@ Published 20 December 2004 Genome Biology 2004 6 R4 The electronic version of this article is the complete one and can be found online at http 2004 6 1 R4 Received 12 August 2004 Revised 26 October 2004 Accepted 24 November 2004 2004 Tasneem et al. licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Acetylcholine receptor type ligand-gated ion channels ART-LGIC also known as Cys-loop receptors are a superfamily of proteins that include the receptors for major neurotransmitters such as acetylcholine serotonin glycine GABA glutamate and histamine and for Zn2 ions. They play a central role in fast synaptic signaling in animal nervous systems and so far have not been found outside of the Metazoa. Results Using sensitive sequence-profile searches we have identified homologs of ART-LGICs in several bacteria and a single archaeal genus Methanosarcina. The homology between the animal receptors and the prokaryotic homologs spans the entire length of the former including both the ligand-binding and channel-forming transmembrane domains. A sequence-structure analysis using the structure of Lymnaea stagnalis acetylcholine-binding protein and the newly detected prokaryotic versions .
