PMID- 10364201
OWN - NLM
STAT- MEDLINE
DCOM- 19990715
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 25
DP  - 1999 Jun 18
TI  - Calnexin interaction with N-glycosylation mutants of a polytopic membrane
      glycoprotein, the human erythrocyte anion exchanger 1 (band 3).
PG  - 17635-42
AB  - The interaction of the endoplasmic reticulum chaperone calnexin with
      N-glycosylation mutants of a polytopic membrane glycoprotein, the human
      erythrocyte anion exchanger (AE1), was characterized by cell-free translation and
      in transfected HEK293 cells, followed by co-immunoprecipitation using
      anti-calnexin antibody. AE1 contains 12-14 transmembrane segments and has a
      single site of N-glycosylation at Asn-642 in the fourth extracytosolic loop. This
      site was mutated (N642D) to create a nonglycosylated protein. Calnexin showed a
      preferential interaction with N-glycosylated AE1 relative to nonglycosylated AE1 
      both in vitro and in vivo. This interaction could be blocked by inhibition of
      glucosidases I and II with castanospermine. Calnexin had access to novel
      N-glycosylated sites created in other extracytosolic loops in AE1 by
      site-directed or insertional mutagenesis. The interaction with AE1 was enhanced
      when multiple sites were introduced into the same loop or into two different
      loops. An association of calnexin with truncated versions of N-glycosylated AE1
      was detected after release of the nascent chains from ribosomes with puromycin.
      The results show that the interaction of calnexin with the polytopic membrane
      glycoprotein AE1 was dependent on the presence but not the location of the
      oligosaccharide. Furthermore, calnexin was associated with AE1 after release of
      AE1 from the translocation machinery.
FAU - Popov, M
AU  - Popov M
AD  - Medical Research Council Group in Membrane Biology, Departments of Medicine and
      Biochemistry, University of Toronto, Ontario M5S 1A8, Canada.
FAU - Reithmeier, R A
AU  - Reithmeier RA
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 (Anion Exchange Protein 1, Erythrocyte)
RN  - 0 (Antiporters)
RN  - 0 (Calcium-Binding Proteins)
RN  - 0 (Chloride-Bicarbonate Antiporters)
RN  - 0 (Membrane Glycoproteins)
RN  - 139873-08-8 (Calnexin)
SB  - IM
MH  - Anion Exchange Protein 1, Erythrocyte/genetics/*metabolism
MH  - Antiporters/genetics/*metabolism
MH  - Calcium-Binding Proteins/*metabolism
MH  - Calnexin
MH  - Cell Line
MH  - Chloride-Bicarbonate Antiporters
MH  - Erythrocytes/*metabolism
MH  - Glycosylation
MH  - Humans
MH  - Membrane Glycoproteins/genetics/metabolism
MH  - Mutation
MH  - Precipitin Tests
MH  - Protein Biosynthesis
MH  - Transfection
EDAT- 1999/06/11 00:00
MHDA- 1999/06/11 00:01
CRDT- 1999/06/11 00:00
PHST- 1999/06/11 00:00 [pubmed]
PHST- 1999/06/11 00:01 [medline]
PHST- 1999/06/11 00:00 [entrez]
AID - 10.1074/jbc.274.25.17635 [doi]
AID - S0021-9258(19)72751-3 [pii]
PST - ppublish
SO  - J Biol Chem. 1999 Jun 18;274(25):17635-42. doi: 10.1074/jbc.274.25.17635.