title: [First open reading frame protein (ORF1p) of the Blattella germanica R1 retroposon and phylogenetically close GAG-like proteins of insects and fungi contain RRM domains].
abstract: The rDNA locus of insects and other arthropods contains non-LTR retrotransposons (retroposons) that are specifically inserted into 28S rRNA genes. The most frequent retroposons are R1 and R2, but the mechanism of insertion and the functions of these mobile elements have not been studied in detail. A clone containing a full-length R1 retroposon copy was islated from the cosmid library of Blattella germanica genes and sequenced. The amino acid sequences encoded by ORF1 of the R1 retroposon were subjected to bioinformatic analysis. It was found that ORF1 of this mobile element encodes a protein (ORF1p) belonging to the superfamily of zinc finger (CCHC) retroviral nucleocapsid proteins and contains two conserved RRM domains (RNA-recognizing motifs) identified on the basis of analysis of the secondary structure of this protein. The discovery of RRM domains in ORF1p of R1 retroposons can contribute to the understanding of the mechanisms of their retrotransposition. We revealed a coiled-coil motif in the N-terminal region of R1 ORF1p, which is similar to the coiled-coil domain involved in homo- or heteromultimerization of proteins and in protein-protein interactions. The domain organization of homologous Gag-like proteins of retroposons in some insects and fungi was found to be similar to the structure established by us for R1 ORF1p of B. germanica.
authors.forename: T V
authors.initials: TV
authors.lastname: Kapelinskaia
authors.forename: A S
authors.initials: AS
authors.lastname: Kagramanova
authors.forename: A L
authors.initials: AL
authors.lastname: Korolev
authors.forename: D V
authors.initials: DV
authors.lastname: Mukha
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D003058:Cockroaches / Q000737:chemistry* / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000737:chemistry / Q000235:genetics; D019476:Insect Proteins / Q000737:chemistry* / Q000235:genetics; D016366:Open Reading Frames / Q000502:physiology*; D018626:Retroelements / Q000502:physiology*; D040681:Structural Homology, Protein; D016335:Zinc Fingers
chemical_list: D005656:Fungal Proteins; D019476:Insect Proteins; D018626:Retroelements