PMID- 7093224
OWN - NLM
STAT- MEDLINE
DCOM- 19820910
LR  - 20190613
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 21
IP  - 9
DP  - 1982 Apr 27
TI  - Binding of a glucagon photoaffinity label to rat liver plasma membranes and its 
      effect on adenylate cyclase activity before and after photolysis.
PG  - 1989-96
AB  - The concentration-dependent stimulation of adenylate cyclase by the photoaffinity 
      reagent 2-[(2-nitro-4-azidophenyl)sulfenyl]-Trp25-glucagon (glucagon-NAPS) and 
      also its binding characteristics were compared with those of the native hormone. 
      The derivative was found to be slightly more potent in stimulating adenylate 
      cyclase than glucagon, in the presence of guanosine 5'-triphosphate (GTP). 
      125I-Labeled glucagon-NAPS or 125I-labeled glucagon bound rapidly to receptors 
      and was competitively displaced by unlabeled glucagon or glucagon-NAPS. 
      Glucagon-NAPS displaced bound radiolabeled hormone at a lower concentration than 
      did glucagon in the absence of GTP. Scatchard analysis of the binding data 
      obtained from displacement of bound radiolabeled ligand with unlabeled peptide 
      demonstrated a heterogeneous population of saturable glucagon binding sites. 
      Glucagon-NAPS displayed a higher affinity (0.7 nM) for the high-capacity sites 
      (80-90% of total binding sites) than glucagon (4.0 nM) in the absence of GTP. In 
      the presence of the nucleotide, both ligands had approximately the same affinity 
      (0.5-0.6 nM). Hill plot analysis of the binding data suggested noncooperative 
      interactions. Photoaffinity labeling of plasma membranes with glucagon-NAPS 
      resulted in an irreversible activation of adenylate cyclase with a reduced 
      response to further stimulation by glucagon, glucagon-NAPS, and NaF.
FAU - Demoliou-Mason, C
AU  - Demoliou-Mason C
FAU - Epand, R M
AU  - Epand RM
LA  - eng
GR  - AM 21285/AM/NIADDK NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Affinity Labels)
RN  - 0 (Azides)
RN  - 76359-36-9 (glucagon, 2-nitro-4-azidophenylsulfenyl-)
RN  - 9007-92-5 (Glucagon)
RN  - EC 4.6.1.1 (Adenylyl Cyclases)
SB  - IM
MH  - Adenylyl Cyclases/*metabolism
MH  - Affinity Labels/metabolism
MH  - Animals
MH  - Azides/*metabolism/pharmacology
MH  - Binding Sites
MH  - Cell Membrane/metabolism
MH  - Glucagon/*metabolism/pharmacology
MH  - In Vitro Techniques
MH  - Kinetics
MH  - Liver/*metabolism
MH  - Photolysis
MH  - Rats
EDAT- 1982/04/27 00:00
MHDA- 1982/04/27 00:01
CRDT- 1982/04/27 00:00
PHST- 1982/04/27 00:00 [pubmed]
PHST- 1982/04/27 00:01 [medline]
PHST- 1982/04/27 00:00 [entrez]
AID - 10.1021/bi00538a003 [doi]
PST - ppublish
SO  - Biochemistry. 1982 Apr 27;21(9):1989-96. doi: 10.1021/bi00538a003.