Cc RNase: the Ceratitis capitata ortholog of a novel highly conserved protein family in metazoans.
Complementary DNA encoding a protein, designated Cc RNase, was isolated from the insect Ceratitis capitata. Deduced amino acid sequence analysis demonstrates that the Cc RNase has strong sequence homology with other uncharacterized proteins predicted from EST sequences belonging to different animal species, therefore defining a new protein family, which is conserved from Caenorhabditis elegans to humans. Phylogenetic analysis data in addition to extensive homolog searches in all available complete genomes suggested that all family members are true orthologs. Proteins belonging to this family are composed of 95-101 amino acids. The C.capitata orthologous protein was expressed in Escherichia coli. Despite the fact that the amino acid sequence of Cc RNase does not share any significant similarities with other known ribonucleases, our data give strong evidence in support of the assignment of enzymatic activity to the recombinant protein. The expressed molecule exhibits ribonucleolytic activity against poly(C) and poly(U) synthetic substrates, as well as rRNA. It is also demonstrated that expression of Cc RNase in E.coli inhibits growth of the host cells.
Rampias
Theodoros N
TN
University of Athens, Faculty of Biology, Department of Biochemistry and Molecular Biology, Panepistimioupolis, 15701 Athens, Greece.
Sideris
Diamantis C
DC
Fragoulis
Emmanuel G
EG
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D033622:Ceratitis capitata / Q000201:enzymology*; D018076:DNA, Complementary / Q000032:analysis / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D011994:Recombinant Proteins / Q000032:analysis / Q000302:isolation & purification; D012260:Ribonucleases / Q000145:classification* / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D011994:Recombinant Proteins; D012260:Ribonucleases