PMID- 9452480
OWN - NLM
STAT- MEDLINE
DCOM- 19980305
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 273
IP  - 6
DP  - 1998 Feb 6
TI  - Specific substitutions at amino acid 256 of the sarcoplasmic/endoplasmic 
      reticulum Ca2+ transport ATPase mediate resistance to thapsigargin in 
      thapsigargin-resistant hamster cells.
PG  - 3542-6
AB  - High levels of resistance to thapsigargin (TG), a specific inhibitor of 
      intracellular Ca2+ transport ATPases (SERCAs), can be developed in culture by 
      stepwise exposure of mammalian cells to increasing concentrations of TG. We have 
      identified, in two independently selected TG-resistant hamster cell lines of 
      different lineages, mutant forms of SERCA. In the TG-resistant Chinese hamster 
      lung fibroblast cell line DC-3F/TG, a T --> C change at nucleotide 766 introduces 
      a Phe256 --> Leu alteration within the first cytosolic loop of the SERCA. In 
      contrast, in the TG-resistant Syrian hamster smooth muscle cell line DDT/TG 4 
      microM, a T --> C change at nucleotide 767 introduces a Phe256 --> Ser mutation 
      at that position. When these specific mutations are introduced into a wild-type 
      full-length avian SERCA1 cDNA, transfection experiments reveal that Ca2+ 
      transport function and ATP hydrolytic activity are not altered by such mutations. 
      However, a 4-5-fold resistance to TG inhibition of Ca2+ transport function occurs 
      upon the introduction of either the Phe256 --> Leu or the Phe256 --> Ser mutation 
      into wild-type SERCA1. These specific mutations also render the hydrolytic 
      activity of the ATPase resistant to inhibition by TG. Our results not only 
      implicate amino acid 256 in TG-SERCA interactions, but also demonstrate that 
      specific mutations within SERCA can mediate resistance to TG.
FAU - Yu, M
AU  - Yu M
AD  - Division of Oncology, Department of Medicine, Greenebaum Cancer Center, 
      Baltimore, Maryland 21201, USA.
FAU - Zhong, L
AU  - Zhong L
FAU - Rishi, A K
AU  - Rishi AK
FAU - Khadeer, M
AU  - Khadeer M
FAU - Inesi, G
AU  - Inesi G
FAU - Hussain, A
AU  - Hussain A
LA  - eng
GR  - P01HL27867/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
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 (Amino Acids)
RN  - 67526-95-8 (Thapsigargin)
RN  - EC 7.2.2.10 (Calcium-Transporting ATPases)
SB  - IM
EIN - J Biol Chem. 1998 May 22;273(21): 13366. Zhang L [corrected to Zhong L]
MH  - Amino Acids/*metabolism
MH  - Animals
MH  - COS Cells
MH  - Calcium-Transporting ATPases/chemistry/*drug effects/metabolism
MH  - Cell Line
MH  - Cricetinae
MH  - Cricetulus
MH  - Drug Resistance
MH  - Endoplasmic Reticulum/*drug effects/enzymology
MH  - Mesocricetus
MH  - Muscle, Smooth/cytology/drug effects/enzymology
MH  - Mutagenesis, Site-Directed
MH  - Polymerase Chain Reaction
MH  - Sarcoplasmic Reticulum/*drug effects/enzymology
MH  - Thapsigargin/*pharmacology
EDAT- 1998/03/07 00:00
MHDA- 1998/03/07 00:01
CRDT- 1998/03/07 00:00
PHST- 1998/03/07 00:00 [pubmed]
PHST- 1998/03/07 00:01 [medline]
PHST- 1998/03/07 00:00 [entrez]
AID - S0021-9258(18)93762-2 [pii]
AID - 10.1074/jbc.273.6.3542 [doi]
PST - ppublish
SO  - J Biol Chem. 1998 Feb 6;273(6):3542-6. doi: 10.1074/jbc.273.6.3542.