HemK, a class of protein methyl transferase with similarity to DNA methyl transferases, methylates polypeptide chain release factors, and hemK knockout induces defects in translational termination

被引:101
作者
Nakahigashi, K [1 ]
Kubo, N
Narita, S
Shimaoka, T
Goto, S
Oshima, T
Mori, H
Maeda, M
Wada, C
Inokuchi, H
机构
[1] Kyoto Univ, Grad Sch Sci, Dept Biophys, Sakyo Ku, Kyoto 6068502, Japan
[2] Japan Sci & Technol Corp, Core Res Evolut Sci & Technol, Ikoma, Nara 6300101, Japan
[3] Nara Inst Sci & Technol, Res & Educ Ctr Genet Informat, Ikoma, Nara 6300101, Japan
[4] Kyoto Univ, Inst Virus Res, Sakyo Ku, Kyoto 6068507, Japan
关键词
D O I
10.1073/pnas.032488499
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
HemK, a universally conserved protein of unknown function, has high amino acid similarity with DNA-(adenine-N6) methyl transferases (MTases). A certain mutation in hemK gene rescues the photosensitive phenotype of a ferrochelatase-deficient (hemH) mutant in Escherichia coli. A hemK knockout strain of E coli not only suffered severe growth defects, but also showed a global shift in gene expression to anaerobic respiration, as determined by microarray analysis, and this shift may lead to the abrogation of photosensitivity by reducing the oxidative stress. Suppressor mutations that abrogated the growth defects of the hemK knockout strain were isolated and shown to be caused by a threonine to alanine change at codon 246 of polypeptide chain release factor (RF) 2, indicating that hemK plays a role in translational termination. Consistent with such a role, the hemK knockout strain showed an enhanced rate of read-through of nonsense codons and induction of transfer-mRNA-mediated tagging of proteins within the cell. By analysis of the methylation of RF1 and RF2 in vivo and in vitro, we showed that HemK methylates RF1 and RF2 in vitro within the tryptic fragment containing the conserved GGQ motif, and that hemK is required for the methylation within the same fragment of, at least, RF1 in vivo, This is an example of a protein AATase containing the DNA MTase motif and also a protein-(glutamine-N5) MTase.
引用
收藏
页码:1473 / 1478
页数:6
相关论文
共 36 条
  • [1] IDENTIFICATION OF AN OCHRE-SUPPRESSING ANTICODON
    ALTMAN, S
    BRENNER, S
    SMITH, JD
    [J]. JOURNAL OF MOLECULAR BIOLOGY, 1971, 56 (01) : 195 - &
  • [2] Bachmann B., 1996, Escherichia coli and Salmonella: cellular and molecular biology, V2, P2460
  • [3] The complete genome sequence of Escherichia coli K-12
    Blattner, FR
    Plunkett, G
    Bloch, CA
    Perna, NT
    Burland, V
    Riley, M
    ColladoVides, J
    Glasner, JD
    Rode, CK
    Mayhew, GF
    Gregor, J
    Davis, NW
    Kirkpatrick, HA
    Goeden, MA
    Rose, DJ
    Mau, B
    Shao, Y
    [J]. SCIENCE, 1997, 277 (5331) : 1453 - +
  • [4] Is the HemK family of putative S-adenosylmethionine-dependent methyltransferases a "missing" ζ subfamily of adenine methyltransferases?: A hypothesis
    Bujnicki, JM
    Radlinska, N
    [J]. IUBMB LIFE, 1999, 48 (03) : 247 - 249
  • [5] Phylogenomic analysis of 16S rRNA:(guanine-N2) methyltransferases suggests new family members and reveals highly conserved motifs and a domain structure similar to other nucleic acid amino-methyltransferases
    Bujnicki, JM
    [J]. FASEB JOURNAL, 2000, 14 (14) : 2365 - 2368
  • [6] Molecular evolution of DNA-(cytosine-N4) methyltransferases: evidence for their polyphyletic origin
    Bujnicki, JM
    Radlinska, M
    [J]. NUCLEIC ACIDS RESEARCH, 1999, 27 (22) : 4501 - 4509
  • [7] A post-translational modification in the GGQ motif of RF2 from Escherichia coli stimulates termination of translation
    Dinçbas-Renqvist, V
    Engström, Å
    Mora, L
    Heurgué-Hamard, V
    Buckingham, R
    Ehrenberg, M
    [J]. EMBO JOURNAL, 2000, 19 (24) : 6900 - 6907
  • [9] Fauman EB., 1999, S ADENOSYLMETHIONINE, P1, DOI DOI 10.1142/9789812813077_0001
  • [10] Mutations in the highly conserved GGQ motif of class 1 polypeptide release factors abolish ability of human eRF1 to trigger peptidyl-tRNA hydrolysis
    Frolova, LY
    Tsivkovskii, RY
    Sivolobova, GF
    Oparina, NY
    Serpinsky, OI
    Blinov, VM
    Tatkov, SI
    Kisselev, LL
    [J]. RNA, 1999, 5 (08) : 1014 - 1020