Potassium channel block by cytoplasmic polyamines as the mechanism of intrinsic rectification

Anatoli N. Lopatin, Elena N. Makhina, Colin G. Nichols

Research output: Contribution to journalArticle

701 Scopus citations

Abstract

INWARDLY rectifying potassium channels conduct ions more readily in the inward than the outward direction, an essential property for normal electrical activity1,2. Although voltage-dependent block by internal magnesium ions may underlie inward rectification in some channels3-5, an intrinsic voltage-dependent closure of the channel plays a contributory, or even exclusive, role in others4,6-9. Here we report that, rather than being intrinsic to the channel protein, so-called intrinsic rectification of strong inward rectifiers requires soluble factors that are not Mg2+ and can be released from Xenopus oocytes and other cells. Biochemical and biophysical characterization identifies these factors as polyamines (spermine, spermidine, putrescine and cadaverine). The results suggest that intrinsic rectification results from voltage-dependent block of the channel pore by polyamines, not from a voltage sensor intrinsic to the channel protein 10.

Original languageEnglish
Pages (from-to)366-369
Number of pages4
JournalNature
Volume372
Issue number6504
DOIs
StatePublished - Jan 1 1994

Fingerprint Dive into the research topics of 'Potassium channel block by cytoplasmic polyamines as the mechanism of intrinsic rectification'. Together they form a unique fingerprint.

  • Cite this