期刊
JOURNAL OF BIOLOGICAL CHEMISTRY
卷 286, 期 40, 页码 34635-34642出版社
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M111.269647
关键词
-
资金
- National Institutes of Health [NS059841]
- South Plains Foundation (SPF)
- Texas Tech University Health Sciences Center (TTUHSC) School of Medicine
Prokaryotic members of the Cys-loop receptor ligand-gated ion channel superfamily were recently identified. Previously, Cys-loop receptors were only known from multicellular organisms (metazoans). Contrary to the metazoan Cys-loop receptors, the prokaryotic ones consist of an extracellular (ECD) and a transmembrane domain (TMD), lacking the large intracellular domain (ICD) present in metazoa (between transmembrane segments M3 and M4). Using a chimera approach, we added the 115-amino acid ICD from mammalian serotonin type 3A receptors (5-HT3A) to the prokaryotic proton-activated Gloeobacter violaceus ligand-gated ion channel (GLIC). We created 12 GLIC-5-HT3A-ICD chimeras by replacing a variable number of amino acids in the short GLIC M3M4 linker with the entire 5-HT3A-ICD. Two-electrode voltage clamp recordings after expression in Xenopus laevis oocytes showed that only two chimeras were functional and produced currents upon acidification. The pH(50) was comparable with wild-type GLIC. 5-HT3A receptor expression can be inhibited by the chaperone protein RIC-3. We have shown previously that the 5-HT3A-ICD is required for the attenuation of 5-HT-induced currents when RIC-3 is co-expressed with 5-HT3A receptors in X. laevis oocytes. Expression of both functional 5-HT3A chimeras was inhibited by RIC-3 co-expression, indicating appropriate folding of the 5-HT3A-ICD in the chimeras. Our results indicate that the ICD can be considered a separate domain that can be removed from or added to the ECD and TMD while maintaining the overall structure and function of the ECD and TMD.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据