PMID- 9582334
OWN - NLM
STAT- MEDLINE
DCOM- 19980625
LR  - 20240109
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 273
IP  - 21
DP  - 1998 May 22
TI  - Role of the S3 stalk segment in the thapsigargin concentration dependence of 
      sarco-endoplasmic reticulum Ca2+ ATPase inhibition.
PG  - 12994-8
AB  - The sarco-endoplasmic reticulum Ca2+ ATPase (SERCA) is specifically inhibited by 
      thapsigargin (TG), whereas the Na+,K+-ATPase is not. Large chimeric exchanges 
      between Ca2+ and Na+,K+-ATPases (Norregaard, A., Vilsen, B., and Andersen, J. P. 
      (1994) J. Biol. Chem. 269, 26598-26601), as well as photolabeling with a TG azido 
      derivative (Hua, S., and Inesi, G. (1997) Biochemistry 36, 11865-11872), suggest 
      that the S3-M3 (stalk and membrane-bound) region of the Ca2+ ATPase is involved 
      in TG binding. We produced small site-directed changes in the S3 stalk segment of 
      the Ca2+ ATPase and found that mutation of five amino acids to the corresponding 
      Na+,K+-ATPase residues increases by 3 orders of magnitude the TG concentration 
      required for inhibition of Ca2+ ATPase and coupled Ca2+ transport. A single 
      mutation in the S3 stalk segment (Gly257 --> Ile) is sufficient to increase by 1 
      order of magnitude the TG concentration required to produce 50% inhibition. By 
      comparison, mutations yielding a nine-amino acid homology in the M3 transmembrane 
      segment, or a 25-amino acid homology in the S4 stalk segment, do not affect the 
      ATPase sensitivity to TG. We suggest that specific binding of TG to the S3 stalk 
      segment, in addition to stacking of the TG ring structure at the membrane 
      interface, determines the high affinity of the ATPase for the inhibitor.
FAU - Zhong, L
AU  - Zhong L
AD  - Department of Biochemistry and Molecular Biology, University of Maryland School 
      of Medicine, Baltimore, Maryland 21201, USA.
FAU - Inesi, G
AU  - Inesi G
LA  - eng
GR  - P01HL-27867/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Enzyme Inhibitors)
RN  - 67526-95-8 (Thapsigargin)
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - EC 7.2.2.10 (Calcium-Transporting ATPases)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Adenosine Triphosphate/metabolism
MH  - Animals
MH  - Binding Sites
MH  - COS Cells
MH  - Calcium/metabolism
MH  - Calcium-Transporting ATPases/antagonists & inhibitors/genetics/*metabolism
MH  - Chickens
MH  - Endoplasmic Reticulum/*enzymology
MH  - Enzyme Inhibitors/*metabolism
MH  - Hydrolysis
MH  - Mutagenesis, Site-Directed
MH  - Sarcoplasmic Reticulum/*enzymology
MH  - Thapsigargin/*metabolism
EDAT- 1998/05/28 00:00
MHDA- 1998/05/28 00:01
CRDT- 1998/05/28 00:00
PHST- 1998/05/28 00:00 [pubmed]
PHST- 1998/05/28 00:01 [medline]
PHST- 1998/05/28 00:00 [entrez]
AID - S0021-9258(19)57906-6 [pii]
AID - 10.1074/jbc.273.21.12994 [doi]
PST - ppublish
SO  - J Biol Chem. 1998 May 22;273(21):12994-8. doi: 10.1074/jbc.273.21.12994.