Precursor of C4 antisense RNA of bacteriophages P1 and P7 is a substrate for RNase P of Escherichia coli.

AUTOR(ES)

Hartmann, R K

RESUMO

The C4 repressor of the temperate bacteriophages P1 and P7 inhibits antirepressor (Ant) synthesis and is essential for establishment and maintenance of lysogeny. C4 is an antisense RNA acting on a target, Ant mRNA, which is transcribed from the same promoter. The antisense-target RNA interaction requires processing of C4 RNA from a precursor RNA. Here we show that 5' maturation of C4 RNA in vivo depends on RNase P. In vitro, Escherichia coli RNase P and its catalytic RNA subunit (M1 RNA) can generate the mature 5' end of C4 RNA from P1 by a single endonucleolytic cut, whereas RNase P from the E. coli rnpA49 mutant, carrying a missense mutation in the RNase P protein subunit, is defective in the 5' maturation of C4 RNA. Primer extension analysis of RNA transcribed in vivo from a plasmid carrying the P1 c4 gene revealed that 5'-mature C4 RNA was the predominant species in rnpA+ bacteria, whereas virtually no mature C4 RNA was found in the temperature-sensitive rnpA49 strain at the restrictive temperature. Instead, C4 RNA molecules carrying up to five extra nucleotides beyond the 5' end accumulated. The same phenotype was observed in rnpA+ bacteria which harbored a plasmid carrying a P7 c4 mutant gene with a single C-->G base substitution in the structural homologue to the CCA 3' end of tRNAs. Implications of C4 RNA processing for the lysis/lysogeny decision process of bacteriophages P1 and P7 are discussed.

Documentos Relacionados

• The c4 repressor of bacteriophage P1 is a processed 77 base antisense RNA.
• Structural basis for ADP-mediated transcriptional regulation by P1 and P7 ParA
• Specificity determinants of the P1 and P7 plasmid centromere analogs.
• Addiction protein Phd of plasmid prophage P1 is a substrate of the ClpXP serine protease of Escherichia coli.
• Base pairing between Escherichia coli RNase P RNA and its substrate.