The human TruB family of pseudouridine synthase genes, including the Dyskeratosis Congenita 1 gene and the novel member TRUB1.
A novel human gene denominated TruB pseudouridine (psi) synthase homolog 1 (E. coli) (approved symbol, TRUB1) has been identified and characterized. Spanning approximately 40 kb on chromosome 10 and including 8 exons, TRUB1 is the first described human ortholog of bacterial TruB/psi55, a gene involved in tRNA pseudouridinilation. TRUB1 gene encodes a 349-amino acid product, with a VFAVHKPKGPTSA box in positions 71-83 corresponding to motif I of the TruB family (probably involved in conserving protein structure). The TruB domain of TRUB1 lies between W104 and I255, and contains another short motif, GGTLDS AARGVLVV, including the highly conserved D residue that characterizes motif II (involved in uridine recognition and in catalytic function of psi synthases). Northern blot analysis revealed that TRUB1 mRNA is widely expressed in various human tissues (especially heart, skeletal muscle and liver). Phylogenetic analysis of the TruB domain revealed another human gene (approved symbol TRUB2) encoding a conserved TruB domain, located on human chromosome 9. Thus, the human TruB family includes at least three members: i.e. DKC1 (previously identified), TRUB1 and TRUB2. The TRUB1 and TRUB2 products could be the hitherto unidentified human tRNA psi synthases. Although TRUB1 is not highly similar to DKC1/dyskerin (whose mutations cause X-linked dyskeratosis congenita) and putatively affects tRNA rather than rRNA modification, it is the most similar human protein to dyskerin. Study of TRUB1 (and TRUB2) should facilitate understanding of the molecular mechanisms of RNA modification and the involvement of psi synthases in human pathology, including dyskeratosis-like diseases.
Centro di Ricerca in Genetica Molecolare Fondazione CARISBO at the Istituto di Istologia ed Embriologia Generale, University of Bologna, 40126 Bologna, Italy.
Cinzia
C
Zucchini
Pierluigi
P
Strippoli
Alessia
A
Biolchi
Rossella
R
Solmi
Luca
L
Lenzi
Pietro
P
D'Addabbo
Paolo
P
Carinci
Luisa
L
Valvassori
D020413:3' Untranslated Regions; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D019871:Dyskeratosis Congenita / Q000235:genetics*; D020224:Expressed Sequence Tags; D006801:Humans; D019753:Intramolecular Lyases / Q000235:genetics*; D019751:Intramolecular Transferases; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D020413:3' Untranslated Regions; D018076:DNA, Complementary; D012333:RNA, Messenger; D019751:Intramolecular Transferases; C096995:pseudouridine synthases; D019753:Intramolecular Lyases