In vitro phosphorylation of initiation factor 2α (aIF2α) from hyperthermophilic archaeon Pyrococcus horikoshii OT3

Maino Tahara, Akiko Ohsawa, Sakura Saito, Makoto Kimura

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

Eukaryotic initiation factor 2 (eIF2) is a heterotrimeric protein composed of α, β, and γ subunits, of which the α subunit (eIF2α) plays a crucial role in regulation of protein synthesis through phosphorylation at Ser51. All three subunit genes are conserved in Archaea. To examine the properties of archaeal initiation factor 2α (aIF2α), three genes encoding α, β, and γ subunits of aIF2 from the hyperthermophilic archaeon Pyrococcus horikoshii OT3 were expressed in Escherichia coli cells, and the resulting proteins, aIF2α, aIF2β, and aIF2γ, were characterized with reference to the properties of eIF2. aIF2α preferentially interacts with aIF2γ, but does not interact with aIF2β, which is consistent with data obtained with eIF2, of which eIF2γ serves as a core subunit, interacting with eIF2α and eIF2β. It was found that aIF2α was, albeit to a lower degree, phosphorylated by double-stranded RNA-dependent protein kinase (hPKR) from human, and a primary target site was suggested to be Ser48 within aIF2α. This finding led us to the search for a putative aIF2 specific kinase gene (PH0512) in the P. horikoshii genome. The gene product Ph0512p unambiguously phosphorylated aIF2α, and Ser48, as in the phosphorylation by hPKR, was suggested to be a target amino acid residue for the PKR homologue Ph0152p in P. horikoshii. These findings suggest that aIF2α, like eIF2α in eukaryotes, plays a role in regulation of the protein synthesis in Archaea through phosphorylation and dephosphorylation.

Original languageEnglish
Pages (from-to)479-485
Number of pages7
JournalJournal of biochemistry
Volume135
Issue number4
DOIs
Publication statusPublished - Apr 1 2004

Fingerprint

Pyrococcus horikoshii
Prokaryotic Initiation Factor-2
Phosphorylation
Archaea
Eukaryotic Initiation Factor-2
Genes
archaeal initiation factor 2
In Vitro Techniques
eIF-2 Kinase
Proteins
Gene encoding
Double-Stranded RNA
Protein Subunits

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Molecular Biology

Cite this

In vitro phosphorylation of initiation factor 2α (aIF2α) from hyperthermophilic archaeon Pyrococcus horikoshii OT3. / Tahara, Maino; Ohsawa, Akiko; Saito, Sakura; Kimura, Makoto.

In: Journal of biochemistry, Vol. 135, No. 4, 01.04.2004, p. 479-485.

Research output: Contribution to journalArticle

Tahara, Maino ; Ohsawa, Akiko ; Saito, Sakura ; Kimura, Makoto. / In vitro phosphorylation of initiation factor 2α (aIF2α) from hyperthermophilic archaeon Pyrococcus horikoshii OT3. In: Journal of biochemistry. 2004 ; Vol. 135, No. 4. pp. 479-485.
@article{6ead89fa81294b4aa03aba3b62137973,
title = "In vitro phosphorylation of initiation factor 2α (aIF2α) from hyperthermophilic archaeon Pyrococcus horikoshii OT3",
abstract = "Eukaryotic initiation factor 2 (eIF2) is a heterotrimeric protein composed of α, β, and γ subunits, of which the α subunit (eIF2α) plays a crucial role in regulation of protein synthesis through phosphorylation at Ser51. All three subunit genes are conserved in Archaea. To examine the properties of archaeal initiation factor 2α (aIF2α), three genes encoding α, β, and γ subunits of aIF2 from the hyperthermophilic archaeon Pyrococcus horikoshii OT3 were expressed in Escherichia coli cells, and the resulting proteins, aIF2α, aIF2β, and aIF2γ, were characterized with reference to the properties of eIF2. aIF2α preferentially interacts with aIF2γ, but does not interact with aIF2β, which is consistent with data obtained with eIF2, of which eIF2γ serves as a core subunit, interacting with eIF2α and eIF2β. It was found that aIF2α was, albeit to a lower degree, phosphorylated by double-stranded RNA-dependent protein kinase (hPKR) from human, and a primary target site was suggested to be Ser48 within aIF2α. This finding led us to the search for a putative aIF2 specific kinase gene (PH0512) in the P. horikoshii genome. The gene product Ph0512p unambiguously phosphorylated aIF2α, and Ser48, as in the phosphorylation by hPKR, was suggested to be a target amino acid residue for the PKR homologue Ph0152p in P. horikoshii. These findings suggest that aIF2α, like eIF2α in eukaryotes, plays a role in regulation of the protein synthesis in Archaea through phosphorylation and dephosphorylation.",
author = "Maino Tahara and Akiko Ohsawa and Sakura Saito and Makoto Kimura",
year = "2004",
month = "4",
day = "1",
doi = "10.1093/jb/mvh055",
language = "English",
volume = "135",
pages = "479--485",
journal = "Journal of Biochemistry",
issn = "0021-924X",
publisher = "Oxford University Press",
number = "4",

}

TY - JOUR

T1 - In vitro phosphorylation of initiation factor 2α (aIF2α) from hyperthermophilic archaeon Pyrococcus horikoshii OT3

AU - Tahara, Maino

AU - Ohsawa, Akiko

AU - Saito, Sakura

AU - Kimura, Makoto

PY - 2004/4/1

Y1 - 2004/4/1

N2 - Eukaryotic initiation factor 2 (eIF2) is a heterotrimeric protein composed of α, β, and γ subunits, of which the α subunit (eIF2α) plays a crucial role in regulation of protein synthesis through phosphorylation at Ser51. All three subunit genes are conserved in Archaea. To examine the properties of archaeal initiation factor 2α (aIF2α), three genes encoding α, β, and γ subunits of aIF2 from the hyperthermophilic archaeon Pyrococcus horikoshii OT3 were expressed in Escherichia coli cells, and the resulting proteins, aIF2α, aIF2β, and aIF2γ, were characterized with reference to the properties of eIF2. aIF2α preferentially interacts with aIF2γ, but does not interact with aIF2β, which is consistent with data obtained with eIF2, of which eIF2γ serves as a core subunit, interacting with eIF2α and eIF2β. It was found that aIF2α was, albeit to a lower degree, phosphorylated by double-stranded RNA-dependent protein kinase (hPKR) from human, and a primary target site was suggested to be Ser48 within aIF2α. This finding led us to the search for a putative aIF2 specific kinase gene (PH0512) in the P. horikoshii genome. The gene product Ph0512p unambiguously phosphorylated aIF2α, and Ser48, as in the phosphorylation by hPKR, was suggested to be a target amino acid residue for the PKR homologue Ph0152p in P. horikoshii. These findings suggest that aIF2α, like eIF2α in eukaryotes, plays a role in regulation of the protein synthesis in Archaea through phosphorylation and dephosphorylation.

AB - Eukaryotic initiation factor 2 (eIF2) is a heterotrimeric protein composed of α, β, and γ subunits, of which the α subunit (eIF2α) plays a crucial role in regulation of protein synthesis through phosphorylation at Ser51. All three subunit genes are conserved in Archaea. To examine the properties of archaeal initiation factor 2α (aIF2α), three genes encoding α, β, and γ subunits of aIF2 from the hyperthermophilic archaeon Pyrococcus horikoshii OT3 were expressed in Escherichia coli cells, and the resulting proteins, aIF2α, aIF2β, and aIF2γ, were characterized with reference to the properties of eIF2. aIF2α preferentially interacts with aIF2γ, but does not interact with aIF2β, which is consistent with data obtained with eIF2, of which eIF2γ serves as a core subunit, interacting with eIF2α and eIF2β. It was found that aIF2α was, albeit to a lower degree, phosphorylated by double-stranded RNA-dependent protein kinase (hPKR) from human, and a primary target site was suggested to be Ser48 within aIF2α. This finding led us to the search for a putative aIF2 specific kinase gene (PH0512) in the P. horikoshii genome. The gene product Ph0512p unambiguously phosphorylated aIF2α, and Ser48, as in the phosphorylation by hPKR, was suggested to be a target amino acid residue for the PKR homologue Ph0152p in P. horikoshii. These findings suggest that aIF2α, like eIF2α in eukaryotes, plays a role in regulation of the protein synthesis in Archaea through phosphorylation and dephosphorylation.

UR - http://www.scopus.com/inward/record.url?scp=2442714840&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=2442714840&partnerID=8YFLogxK

U2 - 10.1093/jb/mvh055

DO - 10.1093/jb/mvh055

M3 - Article

VL - 135

SP - 479

EP - 485

JO - Journal of Biochemistry

JF - Journal of Biochemistry

SN - 0021-924X

IS - 4

ER -