PMID- 10473538
OWN - NLM
STAT- MEDLINE
DCOM- 19991007
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 37
DP  - 1999 Sep 10
TI  - Molecular identification of the ryanodine receptor pore-forming segment.
PG  - 25971-4
AB  - A sequence motif, GXRXGGGXGD, located in the putative channel-forming domain, is 
      conserved in all known ryanodine receptors and inositol 1,4,5-trisphosphate
      receptors. The functional significance of this conserved region was investigated 
      by using site-directed mutagenesis together with functional assays consisting of 
      Ca(2+) release measurements, [(3)H]ryanodine binding, and single channel
      recordings in planar lipid bilayers. We report here that single point mutations
      introduced into this region of the mouse cardiac ryanodine receptor reduce or
      abolish high affinity [(3)H]ryanodine binding. Single channel analysis revealed
      that a single substitution of alanine for glycine 4824 within this region reduced
      the single channel conductance by 97%, from 798 picosiemens (pS) for the wild
      type channel to 22 pS. The G4824A mutant channel was modulated by Ca(2+), Mg(2+),
      ATP, caffeine, ruthenium red, and ryanodine. Co-expression of the wild type and
      G4824A mutant proteins produced single channels that have intermediate unitary
      conductances of 516, 256, 176, and 60 pS. These data suggest that this conserved 
      region constitutes an essential part of the ryanodine binding site and the
      channel conduction pathway of the ryanodine receptor.
FAU - Zhao, M
AU  - Zhao M
AD  - Cardiovascular Research Group, Department of Physiology, University of Calgary,
      Calgary, Alberta T2N 4N1, Canada.
FAU - Li, P
AU  - Li P
FAU - Li, X
AU  - Li X
FAU - Zhang, L
AU  - Zhang L
FAU - Winkfein, R J
AU  - Winkfein RJ
FAU - Chen, S R
AU  - Chen SR
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Ryanodine Receptor Calcium Release Channel)
RN  - 15662-33-6 (Ryanodine)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Cell Line
MH  - Humans
MH  - Membrane Potentials
MH  - Mice
MH  - Mutagenesis, Site-Directed
MH  - Protein Binding
MH  - Ryanodine/metabolism
MH  - Ryanodine Receptor Calcium Release Channel/chemistry/genetics/*metabolism
EDAT- 1999/09/03 00:00
MHDA- 1999/09/03 00:01
CRDT- 1999/09/03 00:00
PHST- 1999/09/03 00:00 [pubmed]
PHST- 1999/09/03 00:01 [medline]
PHST- 1999/09/03 00:00 [entrez]
AID - 10.1074/jbc.274.37.25971 [doi]
AID - S0021-9258(19)55168-7 [pii]
PST - ppublish
SO  - J Biol Chem. 1999 Sep 10;274(37):25971-4. doi: 10.1074/jbc.274.37.25971.