Disease relevance of rne

• Highly purified RNAase E correctly processed E. coli 5S ribosomal RNA, bacteriophage T4 gene 32 mRNA and E. coli ompA mRNA at sites known to depend on the rne gene for cleavage in vivo [1].
• The isolation was based on the appearance of a particular RNA precursor molecule upon infection of an rne mutant with a specific bacteriophage T4 deletion strain [2].
• This notion is supported by our finding that the Synechocystis sp. RNase E homologue does not function as a platform for assembly of E. coli degradosome components [3].
• Ribonuclease E (RNase E) is a multifunctional endoribonuclease that has been evolutionarily conserved in both Gram-positive and Gram-negative bacteria [4].
• Previous work has detected an RNase E-like endoribonucleolytic activity in cell extracts obtained from Streptomyces [5].

High impact information on rne

• Ribonuclease E (RNase E) has a key role in mRNA degradation and the processing of catalytic and structural RNAs in E. coli [6].
• Initiation of tRNA maturation by RNase E is essential for cell viability in E. coli [7].
• The description of RNase E now emerging is that of a remarkably complex multidomain protein containing an amino-terminal catalytic domain, a central RNA-binding domain, and carboxy-terminal binding sites for the other major components of the RNA degradosome [8].
• These results and an analysis of all of the known putative RNase E sites suggest a consensus sequence RAUUW (R = A or G; W = A or U) at the cleavage site [9].
• We propose that this higher speed unmasks an RNase E cleavage site which is normally shielded by ribosomes soon after its synthesis when the slower E. coli enzyme is used [10].

Chemical compound and disease context of rne

• A Streptomyces peptide migrating at 70kDa in SDS/polyacrylamide gels binds to RNase E substrates and reacts with three separate anti-RNase E monoclonal antibodies; the endonucleolytic cleavage activity co-purified with the immunoreactive 70 kDa peptide [11].
• The effects of erythromycin on the formation of ribosomal subunits were examined in wild-type Escherichia coli cells and in an RNase E mutant strain [12].
• The ptsG mRNA encoding the major glucose transporter is rapidly degraded in an RNase E-dependent manner in response to the accumulation of glucose 6-P or fructose 6-P when the glycolytic pathway is blocked at its early steps in Escherichia coli [13].

Biological context of rne

• IS10 mRNA stability and steady state levels in Escherichia coli: indirect effects of translation and role of rne function [14].
• A functional rne gene product is essential for cell viability and for the processing and/or decay of a variety of RNA species, including 9 S RNA, mRNA and RNAI, the antisense RNA regulator of ColE1-type plasmid replication [15].
• The copy number of plasmid pBR322 in these rne mutants was lower than that in the rne+ isogenic strain [16].
• However, while restoration of the level of FtsZ to normal in rne null mutant bacteria reverses the filamentation phenotype, it does not restore CFA [17].
• Physical locations of genes in the rne (ams)-rpmF-plsX-fab region of the Escherichia coli K-12 chromosome [18].

Anatomical context of rne

• Analysis of interplay between translation mutations and rne function, together with the above observations, suggests that translation stabilizes messages in a general way against rne-dependent endonucleolytic cleavage, and that significant protection may be conferred by one or a few ribosomes [14].
• These results (i) confirm the central role of DsbC in disulfide bond isomerization in the bacterial periplasm and (ii) suggest a critical role for RNase E in regulating DsbC expression [19].

Associations of rne with chemical compounds

• In contrast to the S1 domain, an arginine-rich RNA-binding domain in the carboxyl half of RNase E appears to have a more peripheral role in RNase E function, as it is not required for feedback regulation, cell growth or ribonuclease activity [20].
• The degradation is RNase E dependent and is correlated with the accumulation of either glucose-6-P or fructose-6-P (Kimata et al., 2001, EMBO J 20: 3587-3595; Morita et al., 2003, J Biol Chem 278: 15608-15614) [21].
• Each of the five surface-exposed aromatic residues and most of the 14 basic residues of this RNase E domain were replaced with alanine to determine their importance for RNase E function [20].
• The site for endonucleolytic cleavage is located in the intercistronic region between mopP and catA, and contains a potential stem-loop structure and a putative RNase E cleavage site [22].
• These results indicate that RNase E is required for induction of the glutamate-dependent acid resistance system in a RpoS-independent manner [23].

Enzymatic interactions of rne

• Both enzymes are able to cleave the B.subtilis thrS leader at a site that can also be cleaved by E.coli RNase E. We have previously shown that cleavage at this site increases the stability of the downstream messenger [24].

Other interactions of rne

• As expected, purified degradosomes, a multi-protein complex containing, among others, RNase E, PNPase, and RhlB, generate an authentic 147-residue RNase E cleavage product from the rpsT mRNA in vitro [25].
• Immunoaffinity purification of the Escherichia coli rne gene product. Evidence that the rne gene encodes the processing endoribonuclease RNase E [26].
• The role of enolase within the RNase E-based degradosome in RNA decay has been totally mysterious [13].

Analytical, diagnostic and therapeutic context of rne

• X-ray crystallography and biochemical studies have concluded that the Escherichia coli RNase E protein functions as a homotetramer formed by Zn linkage of dimers within a region extending from amino acid residues 416 through 529 of the 116-kDa protein [4].
• The Western blot analysis performed using a rabbit antiserum raised against a truncated 110-kDa protein fragment of RNase E (containing two-thirds of the sequence from the N terminus) revealed that the 180-kDa polypeptide is the only protein recognized by the antibodies in a wild type whole cell extract of E. coli [26].

References