Structural analysis of the messenger RNA cap-binding protein: presence of phosphate, sulfhydryl, and disulfide groups
The messenger-RNA cap-binding protein (CBP) was isolated from human erythrocyte, rabbit erythrocyte, and rabbit reticulocyte lysate by affinity chromatography on 7-methylguanosine 5'-triphosphate-Sepharose. The specific activity of binding to capped oligonucleotides was similar for the human erythrocyte and rabbit reticulocyte CBPs. Isoelectric focusing of human and rabbit preparations revealed that each was composed of up to five species. The pI values of human and rabbit CBPs ranged from 5.7 to 6.5. The predominant form in erythrocytes had a pI of 6.3 while in reticulocytes, two major species, having pI values of 5.9 and 6.3, were present. Labeling of rabbit reticulocytes with (/sup 32/P)orthophosphate revealed that the pI 5.9 but not the pI 6.3 form contained phosphate. All of the phosphate was found in phosphoserine residues. The amino acid compositions of human erythrocyte and rabbit reticulocyte CBPs were quite similar. Both proteins had 7 tryptophanyl and 6 cysteinyl residues. Labeling with (1-/sup 14/C)iodoacetic acid under native and denaturing conditions provided evidence that 2 of the cysteinyl residues are present in the reduced form and 4 in disulfide bridges.
- Research Organization:
- Univ. of Kentucky, Lexington
- OSTI ID:
- 5150816
- Journal Information:
- J. Biol. Chem.; (United States), Vol. 261:1
- Country of Publication:
- United States
- Language:
- English
Similar Records
Phenyl azide substituted and benzophenone-substituted phosphonamides of 7-methylguanosine 5 prime -triphosphate as photoaffinity probes for protein synthesis initiation factor eIF-4E and a proteolytic fragment containing the cap-binding site
Phosphorylation of the C proteins in heterogeneous ribonucleoprotein (hnRNP) particles in HeLa cells: Characterization of in vivo phosphorylation, comparison with in vitro phosphorylation using casein kinase II, and preliminary studies on the effects of phosphorylation on particle structure
Related Subjects
MESSENGER-RNA
BIOCHEMICAL REACTION KINETICS
PROTEINS
STRUCTURAL CHEMICAL ANALYSIS
AMINO ACIDS
CARBON 14 COMPOUNDS
CHROMATOGRAPHY
CYSTEINE
ERYTHROCYTES
EXPERIMENTAL DATA
LABELLED COMPOUNDS
PHOSPHORUS 32
PROTEIN STRUCTURE
RABBITS
RETICULOCYTES
TRACER TECHNIQUES
TRYPTOPHAN
ANIMALS
AROMATICS
AZAARENES
AZOLES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBOXYLIC ACIDS
DATA
DAYS LIVING RADIOISOTOPES
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INDOLES
INFORMATION
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
MAMMALS
MATERIALS
NUCLEI
NUCLEIC ACIDS
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHOSPHORUS ISOTOPES
PYRROLES
RADIOISOTOPES
REACTION KINETICS
RNA
SEPARATION PROCESSES
THIOLS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques