Glucagon
The effect of glucagon :
Glucagon is the peptide hormone produced by the alpha cells of the
pancreatic islets. The major physiological effects of glucagon are all on
the liver. Clucagon binds to receptors in the plasma membrane of liver
cells, leading to the activation of adenylyl cyclase and generation of
cyclic AMP in the cells. Cyclic AMP in turn activates cAMP-dependent
protein kinases, which phosphorylate enzymes that mediate the effects of
glucagon. All these effects on the liver are opposed to those of insulin:
(1) increased glycogen breakdown; (2) increased gluconeogenesis ; and
(3) synthesis of ketones. Thus, the overall results of glucagon*s effects
are to increase the plasma concentrations of glucose and ketones, which
are important for the postabsorptive period.
PDB header form :
HEADER HORMONE 17-OCT-77 1GCN 1GCN 3
COMPND GLUCAGON (PH 6 - PH 7 FORM) 1GCN 4
SOURCE PORCINE (SUS SCROFA) PANCREAS 1GCN 5
AUTHOR T.L.BLUNDELL,K.SASAKI,S.DOCKERILL,I.J.TICKLE 1GCN 6
REVDAT 5 30-SEP-83 1GCND 1 REVDAT 1GCND 1
REVDAT 4 31-DEC-80 1GCNC 1 REMARK 1GCND 2
REVDAT 3 22-OCT-79 1GCNB 3 ATOM 1GCND 3
REVDAT 2 29-AUG-79 1GCNA 3 CRYST1 1GCND 4
REVDAT 1 28-NOV-77 1GCN 0 1GCND 5
JRNL AUTH K.SASAKI,S.DOCKERILL,D.A.ADAMIAK,I.J.TICKLE, 1GCN 7
JRNL AUTH 2 T.BLUNDELL 1GCN 8
JRNL TITL X-RAY ANALYSIS OF GLUCAGON AND ITS RELATIONSHIP TO 1GCN 9
JRNL TITL 2 RECEPTOR BINDING 1GCN 10
JRNL REF NATURE V. 257 751 1975 1GCN 11
JRNL REFN ASTM NATUAS UK ISSN 0028-0836 006 1GCN 12
REMARK 1 1GCN 13
REMARK 1 REFERENCE 1 1GCN 14
REMARK 1 EDIT M.O.DAYHOFF 1GCN 15
REMARK 1 REF ATLAS OF PROTEIN SEQUENCE V. 5 125 1976 1GCN 16
REMARK 1 REF 2 AND STRUCTURE,SUPPLEMENT 2 1GCN 17
REMARK 1 PUBL NATIONAL BIOMEDICAL RESEARCH FOUNDATION, 1GCN 18
REMARK 1 PUBL 2 SILVER SPRING,MD. 1GCN 19
REMARK 1 REFN ISBN 0-912466-05-7 435 1GCN 20
REMARK 2 1GCN 21
REMARK 2 RESOLUTION. 3.0 ANGSTROMS. 1GCNC 1
REMARK 3 1GCN 23
REMARK 3 REFINEMENT. REALSPACE REFINEMENT AND ENERGY REFINEMENT. 1GCN 24
REMARK 4 1GCN 25
REMARK 4 THE GLUCAGON CRYSTALS ARE FORMED AT PH 9.2 AND THEN THE PH 1GCN 26
REMARK 4 IS CHANGED TO BETWEEN 6 AND 7. CRYSTALS AT BOTH PH,S HAVE 1GCN 27
REMARK 4 HIGH TEMPERATURE FACTORS, AND DATA TERMINATE AT 1GCN 28
REMARK 4 APPROXIMATELY 3 ANGSTROMS RESOLUTION. THE COORDINATES ARE 1GCN 29
REMARK 4 OBTAINED FROM THE 3 ANGSTROMS RESOLUTION ELECTRON DENSITY 1GCN 30
REMARK 4 MAP AND REFINED USING REAL SPACE REFINEMENT AGAINST 1GCN 31
REMARK 4 (2FOBS-FCALC),ALPHA CALC ELECTRON DENSITY MAPS WITH 1GCN 32
REMARK 4 GEOMETRIC RESTRAINTS, FOLLOWED BY LEVITT ENERGY 1GCN 33
REMARK 4 MINIMIZATION. NO SOLVENT CAN BE INCLUDED AT 3 ANGSTROMS. 1GCN 34
REMARK 4 WARNING - LOW RESOLUTION (3 ANGSTROMS) IMPLIES RATHER 1GCN 35
REMARK 4 INACCURATE COORDINATES AND MEANINGLESS TEMPERATURE FACTORS. 1GCN 36
REMARK 5 1GCNA 1
REMARK 5 CORRECTION. MOVE CRYST1 RECORD TO ITS PROPER POSITION. 1GCNA 2
REMARK 5 29-AUG-79. 1GCNA 3
REMARK 6 1GCNB 1
REMARK 6 CORRECTION. FIX NAMING AND HENCE ORDERING OF TWO ATOMS. 1GCNB 2
REMARK 6 22-OCT-79. 1GCNB 3
REMARK 7 1GCNC 2
REMARK 7 CORRECTION. STANDARDIZE FORMAT OF REMARK 2. 31-DEC-80. 1GCNC 3
REMARK 8 1GCND 6
REMARK 8 CORRECTION. INSERT REVDAT RECORDS. 30-SEP-83. 1GCND 7
SEQRES 1 29 HIS SER GLN GLY THR PHE THR SER ASP TYR SER LYS TYR 1GCN 37
SEQRES 2 29 LEU ASP SER ARG ARG ALA GLN ASP PHE VAL GLN TRP LEU 1GCN 38
SEQRES 3 29 MET ASN THR 1GCN 39
FTNOTE 1 1GCN 40
FTNOTE 1 RESIDUES 1 THROUGH 5 ARE RATHER DISORDERED IN THE CRYSTALS. 1GCN 41
HELIX 1 A PHE 6 LEU 26 1 1GCN 42
CRYST1 47.100 47.100 47.100 90.00 90.00 90.00 P 21 3 12 1GCNA 4
ORIGX1 .021231 0.000000 0.000000 0.000000 1GCN 43
ORIGX2 0.000000 .021231 0.000000 0.000000 1GCN 44
ORIGX3 0.000000 0.000000 .021231 0.000000 1GCN 45
SCALE1 .021231 0.000000 0.000000 0.000000 1GCN 46
SCALE2 0.000000 .021231 0.000000 0.000000 1GCN 47
SCALE3 0.000000 0.000000 .021231 0.000000 1GCN 48
The structure of glucagon :
