Sensing the air around us The voltage gated like ion channel family英文电子书.pdf

Sensing the Air Around Us: The Voltage-Gated-Like Ion Channel Family Dennis Kim, MD, and James N. Baraniuk, MD Corresponding author single pore structure. Several of these families of proteins James N. Baraniuk, MD form tetramers with a central pore and peripherally radi- Division of Rheumatology, Immunology and Allergy, Room B105, Lower Level Kober-Cogen Building, Georgetown University, 3800 ating transmembrane helices. Reservoir Road, NW, Washington, DC 20007-2197, USA. Characteristic charged amino acids within this loop E-mail: baraniuj@ and the transmembrane helices determine the cation selec- + + 2+ 2+ Current Allergy and Asthma Reports 2007, 7:85–92 tivity for Na , K , Ca , and Mg . These regions control Current Medicine Group LLC ISSN 1529-7322 the lux of ions through these pores and direction of ion Copyright © 2007 by Current Medicine Group LLC transfer (inward or outward). This gating of ion conduc- tance determines the role of each protein in membrane depolarization and repolarization. Ion channels are a complex set of proteins having many These processes can be modiied by adjacent proteins, important physiologic and potentially pathologic roles. secondary me