Abstract
Inward-rectifier, G-protein-regulated and ATP-dependent K+ channels form a novel gene family of related proteins which share two transmembrane segments as a common structural feature. These K+ channels are only distantly related to the voltage-gated Shaker-type K+ channels comprising six extensively studied in the past, little is known about subunit assembly of inward-rectifier K+ channels. Differential sensitivity of inward-rectifier K+ channels to voltage-dependent pore block by spermine was used to analyse subunit assembly. It is shown that inward-rectifier K+ channel proteins are composed of four subunits whose assembly obeys the rules of a binomial distribution. 'Strong' and 'mild' inward-rectifier K+ channel subunits (BIR10 and ROMK1) which are co-expressed in individual auditory hair cells form hetero-tetramers. Distribution of these hetero-tetramers, however, is not binomial. Hetero- and homo-oligomeric channels form with similar probabilities resulting in independent channel populations with distinct functional properties.
Original language | English (US) |
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Pages (from-to) | 251-261 |
Number of pages | 11 |
Journal | Proceedings of the Royal Society B: Biological Sciences |
Volume | 261 |
Issue number | 1361 |
DOIs | |
State | Published - 1995 |
Externally published | Yes |
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- General Immunology and Microbiology
- General Environmental Science
- General Agricultural and Biological Sciences