A candidate prostate cancer susceptibility gene encodes tRNA 3' processing endoribonuclease.
tRNA 3' processing endoribonuclease (3' tRNase) is an enzyme responsible for the removal of a 3' trailer from precursor tRNA (pre-tRNA). We purified approximately 85 kDa 3' tRNase from pig liver and determined its partial sequences. BLAST search of them suggested that the enzyme was the product of a candidate human prostate cancer susceptibility gene, ELAC2, the biological function of which was totally unknown. We cloned a human ELAC2 cDNA and expressed the ELAC2 protein in Escherichia coli. The recombinant ELAC2 was able to cleave human pre-tRNA(Arg) efficiently. The 3' tRNase activity of the yeast ortholog YKR079C was also observed. The C-terminal half of human ELAC2 was able to remove a 3' trailer from pre-tRNA(Arg), while the N-terminal half failed to do so. In the human genome exists a gene, ELAC1, which seems to correspond to the C-terminal half of 3' tRNase from ELAC2. We showed that human ELAC1 also has 3'-tRNase activity. Furthermore, we examined eight ELAC2 variants that seem to be associated with the occurrence of prostate cancer for 3'-tRNase activity. Seven ELAC2 variants which contain one to three amino acid substitutions showed efficient 3'-tRNase activities, while one truncated variant, which lacked a C-terminal half region, had no activity.
Takaku
Hiroaki
H
Department of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, Higashijima 265-1, Niitsu, Niigata 956-8603, Japan.
Minagawa
Asako
A
Takagi
Masamichi
M
Nashimoto
Masayuki
M
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004722:Endoribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000235:genetics; D011471:Prostatic Neoplasms / Q000201:enzymology / Q000235:genetics; D012322:RNA Precursors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012347:RNA, Transfer, Arg / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D013552:Swine
D018076:DNA, Complementary; C421605:ELAC2 protein, human; D009363:Neoplasm Proteins; D012322:RNA Precursors; D012347:RNA, Transfer, Arg; D011994:Recombinant Proteins; D004722:Endoribonucleases; C045782:3'-pre-tRNase