Multiple regulatory sites in large-conductance calcium-activated potassium channels

Xiao-Ming Xia, Xuhui Zeng and Christopher J. Lingle ()
Additional contact information
Xiao-Ming Xia: Washington University School of Medicine
Xuhui Zeng: Washington University School of Medicine
Christopher J. Lingle: Washington University School of Medicine

Nature, 2002, vol. 418, issue 6900, 880-884

Abstract: Abstract Large conductance, Ca2+- and voltage-activated K+ channels (BK) respond to two distinct physiological signals—membrane voltage and cytosolic Ca2+ (refs 1, 2). Channel opening is regulated by changes in Ca2+ concentration spanning 0.5 µM to 50 mM (refs 2–5), a range of Ca2+ sensitivity unusual among Ca2+-regulated proteins. Although voltage regulation arises from mechanisms shared with other voltage-gated channels6,7,8, the mechanisms of Ca2+ regulation remain largely unknown. One potential Ca2+-regulatory site, termed the ‘Ca2+ bowl’, has been located to the large cytosolic carboxy terminus9,10,11. Here we show that a second region of the C terminus, the RCK domain (regulator of conductance for K+ (ref. 12)), contains residues that define two additional regulatory effects of divalent cations. One site, together with the Ca2+ bowl, accounts for all physiological regulation of BK channels by Ca2+; the other site contributes to effects of millimolar divalent cations that may mediate physiological regulation by cytosolic Mg2+ (refs 5, 13). Independent regulation by multiple sites explains the large concentration range over which BK channels are regulated by Ca2+. This allows BK channels to serve a variety of physiological roles contingent on the Ca2+ concentration to which the channels are exposed14,15.

Date: 2002
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/nature00956 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:418:y:2002:i:6900:d:10.1038_nature00956

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/nature00956

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().