This proposal investigates the molecular mechanisms of K selectivity and inward rectification in IRK channels expressed in Xenopus oocytes. In particular, the investigator will investigate the selectivity of the K binding site using selective IRK channel mutants, and rectification that results from intracellular blocking ions. The ROMK1 and IRK1 channels are appropriate channels on which to carry out these investigations. The mutant channels that conduct fall into two categories: those that have ion selectivity like WT channel and those that are nonselective. The proposal investigates the mechanisms rectification and the interactions of specific polyamines with rectifying channels.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM055560-05
Application #
6386665
Study Section
Physiology Study Section (PHY)
Program Officer
Shapiro, Bert I
Project Start
1997-05-01
Project End
2002-04-30
Budget Start
2001-05-01
Budget End
2002-04-30
Support Year
5
Fiscal Year
2001
Total Cost
$236,642
Indirect Cost
Name
University of Pennsylvania
Department
Physiology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
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Ramu, Yajamana; Xu, Yanping; Shin, Hyeon-Gyu et al. (2014) Counteracting suppression of CFTR and voltage-gated K+ channels by a bacterial pathogenic factor with the natural product tannic acid. Elife 3:e03683
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Xu, Yanping; Shin, Hyeon-Gyu; Szép, Szilvia et al. (2009) Physical determinants of strong voltage sensitivity of K(+) channel block. Nat Struct Mol Biol 16:1252-8