The abundant class of nemis repeats provides RNA substrates for ribonuclease III in Neisseriae.
About 2% of the Neisseria meningitidis genome is made up by nemis, short DNA sequences which feature long terminal inverted repeats (TIRs). Most nemis are interspersed with single-copy DNA and are found at close distance from cellular genes. In this work, we demonstrate than RNAs spanning nemis of different length and sequence compositions are specifically cleaved at hairpins formed by nemis termini by total cellular lysates derived from both Escherichia coli and Neisseria lactamica strains. The use of cellular extracts from E. coli strains impaired in the activity of known ribonucleases let to establish that cleavage at nemis TIRs is specifically mediated by the endoribonuclease RNase III. Data set the base for the identification of all of the neisserial genes that are regulated by RNase III because of their physical association with nemis DNA.
De Gregorio
Eliana
E
Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università degli Studi di Napoli Federico II, Via S. Pansini 5, 80131 Naples, Italy.
Abrescia
Chiara
C
Carlomagno
M Stella
MS
Di Nocera
Pier Paolo
PP
D001665:Binding Sites; D004722:Endoribonucleases / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D009345:Neisseria meningitidis / Q000201:enzymology / Q000235:genetics*; D010957:Plasmids; D043244:Ribonuclease III; D013045:Species Specificity; D020079:Terminal Repeat Sequences
D029968:Escherichia coli Proteins; D004722:Endoribonucleases; D043244:Ribonuclease III; C468366:ribonuclease III, E coli