Characterization of eukaryotic initiation factor 5 from rabbit reticulocytes. Evidence that the initiation factor is a monomeric protein of Mr of about 58,000-62,000.

P. Raychaudhuri, J. Chevesich, S. Ghosh, U. Maitra

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Eukaryotic initiation factor 5 (eIF-5) has been purified from the ribosomal salt-wash proteins of rabbit reticulocyte lysates. The purified factor migrates as a single polypeptide upon sodium dodecyl sulfate-gel electrophoresis with an apparent Mr of about 58,000-62,000. In contrast, less pure preparations of reticulocyte eIF-5 behave in gel filtration columns and in glycerol gradient centrifugation in buffers containing 75-100 mM KCl as a protein of apparent Mr = 140,000-160,000. Presumably, this is due to association of the factor with other proteins, since eIF-5 activity present in such preparations can also be shown by (a) glycerol gradient centrifugation in buffers containing 500 mM KCl or (b) gel electrophoresis under denaturing conditions, to be associated with a 58,000-62,000-dalton protein. Furthermore, eIF-5 purified from rabbit reticulocyte lysates in the absence or presence of protease inhibitors is indistinguishable with regard to molecular weight and final specific activity. It can be calculated that 1 pmol of the purified eIF-5 catalyzes the formation of nearly 50 pmol of 80 S initiation complex under in vitro initiation reaction conditions. Because of the highly catalytic activity of eIF-5 in initiation reactions, the presence of even low levels of eIF-5 in eIF-2 preparations causes hydrolysis of GTP bound to the 40 S initiation complex. This results in destabilization of Met-tRNA(f) bound to the 40 S complex in sucrose gradient centrifugation.

Original languageEnglish (US)
Pages (from-to)14222-14227
Number of pages6
JournalJournal of Biological Chemistry
Volume262
Issue number29
StatePublished - Oct 15 1987

Fingerprint

Eukaryotic Initiation Factor-5
Peptide Initiation Factors
Reticulocytes
Rabbits
Centrifugation
Proteins
Gels
Electrophoresis
Glycerol
Buffers
Guanosine Triphosphate
Protease Inhibitors
Sodium Dodecyl Sulfate
Gel Chromatography
Sucrose
Hydrolysis
Catalyst activity
Salts
Molecular Weight
Molecular weight

ASJC Scopus subject areas

  • Biochemistry

Cite this

Characterization of eukaryotic initiation factor 5 from rabbit reticulocytes. Evidence that the initiation factor is a monomeric protein of Mr of about 58,000-62,000. / Raychaudhuri, P.; Chevesich, J.; Ghosh, S.; Maitra, U.

In: Journal of Biological Chemistry, Vol. 262, No. 29, 15.10.1987, p. 14222-14227.

Research output: Contribution to journalArticle

@article{b131ded3497c4ffa9976d498a38c9f8e,
title = "Characterization of eukaryotic initiation factor 5 from rabbit reticulocytes. Evidence that the initiation factor is a monomeric protein of Mr of about 58,000-62,000.",
abstract = "Eukaryotic initiation factor 5 (eIF-5) has been purified from the ribosomal salt-wash proteins of rabbit reticulocyte lysates. The purified factor migrates as a single polypeptide upon sodium dodecyl sulfate-gel electrophoresis with an apparent Mr of about 58,000-62,000. In contrast, less pure preparations of reticulocyte eIF-5 behave in gel filtration columns and in glycerol gradient centrifugation in buffers containing 75-100 mM KCl as a protein of apparent Mr = 140,000-160,000. Presumably, this is due to association of the factor with other proteins, since eIF-5 activity present in such preparations can also be shown by (a) glycerol gradient centrifugation in buffers containing 500 mM KCl or (b) gel electrophoresis under denaturing conditions, to be associated with a 58,000-62,000-dalton protein. Furthermore, eIF-5 purified from rabbit reticulocyte lysates in the absence or presence of protease inhibitors is indistinguishable with regard to molecular weight and final specific activity. It can be calculated that 1 pmol of the purified eIF-5 catalyzes the formation of nearly 50 pmol of 80 S initiation complex under in vitro initiation reaction conditions. Because of the highly catalytic activity of eIF-5 in initiation reactions, the presence of even low levels of eIF-5 in eIF-2 preparations causes hydrolysis of GTP bound to the 40 S initiation complex. This results in destabilization of Met-tRNA(f) bound to the 40 S complex in sucrose gradient centrifugation.",
author = "P. Raychaudhuri and J. Chevesich and S. Ghosh and U. Maitra",
year = "1987",
month = "10",
day = "15",
language = "English (US)",
volume = "262",
pages = "14222--14227",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "29",

}

TY - JOUR

T1 - Characterization of eukaryotic initiation factor 5 from rabbit reticulocytes. Evidence that the initiation factor is a monomeric protein of Mr of about 58,000-62,000.

AU - Raychaudhuri, P.

AU - Chevesich, J.

AU - Ghosh, S.

AU - Maitra, U.

PY - 1987/10/15

Y1 - 1987/10/15

N2 - Eukaryotic initiation factor 5 (eIF-5) has been purified from the ribosomal salt-wash proteins of rabbit reticulocyte lysates. The purified factor migrates as a single polypeptide upon sodium dodecyl sulfate-gel electrophoresis with an apparent Mr of about 58,000-62,000. In contrast, less pure preparations of reticulocyte eIF-5 behave in gel filtration columns and in glycerol gradient centrifugation in buffers containing 75-100 mM KCl as a protein of apparent Mr = 140,000-160,000. Presumably, this is due to association of the factor with other proteins, since eIF-5 activity present in such preparations can also be shown by (a) glycerol gradient centrifugation in buffers containing 500 mM KCl or (b) gel electrophoresis under denaturing conditions, to be associated with a 58,000-62,000-dalton protein. Furthermore, eIF-5 purified from rabbit reticulocyte lysates in the absence or presence of protease inhibitors is indistinguishable with regard to molecular weight and final specific activity. It can be calculated that 1 pmol of the purified eIF-5 catalyzes the formation of nearly 50 pmol of 80 S initiation complex under in vitro initiation reaction conditions. Because of the highly catalytic activity of eIF-5 in initiation reactions, the presence of even low levels of eIF-5 in eIF-2 preparations causes hydrolysis of GTP bound to the 40 S initiation complex. This results in destabilization of Met-tRNA(f) bound to the 40 S complex in sucrose gradient centrifugation.

AB - Eukaryotic initiation factor 5 (eIF-5) has been purified from the ribosomal salt-wash proteins of rabbit reticulocyte lysates. The purified factor migrates as a single polypeptide upon sodium dodecyl sulfate-gel electrophoresis with an apparent Mr of about 58,000-62,000. In contrast, less pure preparations of reticulocyte eIF-5 behave in gel filtration columns and in glycerol gradient centrifugation in buffers containing 75-100 mM KCl as a protein of apparent Mr = 140,000-160,000. Presumably, this is due to association of the factor with other proteins, since eIF-5 activity present in such preparations can also be shown by (a) glycerol gradient centrifugation in buffers containing 500 mM KCl or (b) gel electrophoresis under denaturing conditions, to be associated with a 58,000-62,000-dalton protein. Furthermore, eIF-5 purified from rabbit reticulocyte lysates in the absence or presence of protease inhibitors is indistinguishable with regard to molecular weight and final specific activity. It can be calculated that 1 pmol of the purified eIF-5 catalyzes the formation of nearly 50 pmol of 80 S initiation complex under in vitro initiation reaction conditions. Because of the highly catalytic activity of eIF-5 in initiation reactions, the presence of even low levels of eIF-5 in eIF-2 preparations causes hydrolysis of GTP bound to the 40 S initiation complex. This results in destabilization of Met-tRNA(f) bound to the 40 S complex in sucrose gradient centrifugation.

UR - http://www.scopus.com/inward/record.url?scp=0023656515&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023656515&partnerID=8YFLogxK

M3 - Article

C2 - 2820998

AN - SCOPUS:0023656515

VL - 262

SP - 14222

EP - 14227

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 29

ER -