Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.13.1 (
exoribonuclease
)
732
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Many bacteria encode an ortholog of the
Ro60
autoantigen, a ring-shaped protein that is bound in animal cells to noncoding RNAs (ncRNAs) called Y RNAs. Studies in Deinococcus radiodurans revealed that Y RNA tethers
Ro60
to polynucleotide phosphorylase, specializing this
exoribonuclease
for structured RNA degradation. Although
Ro60
orthologs are present in a wide range of bacteria, Y RNAs have been detected in only two species, making it unclear whether these ncRNAs are common
Ro60
partners in bacteria. In this study, we report that likely Y RNAs are encoded near
Ro60
in >250 bacterial and phage species. By comparing conserved features, we discovered that at least one Y RNA in each species contains a domain resembling tRNA. We show that these RNAs contain nucleotide modifications characteristic of tRNA and are substrates for several enzymes that recognize tRNAs. Our studies confirm the importance of Y RNAs in bacterial physiology and identify a new class of ncRNAs that mimic tRNA.
...
PMID:Bacterial noncoding Y RNAs are widespread and mimic tRNAs. 2523 22
Y RNAs are noncoding RNAs (ncRNAs) that are present in most animal cells and also in many bacteria. These RNAs were discovered because they are bound by the
Ro60
protein, a major target of autoantibodies in patients with some systemic autoimmune rheumatic diseases. Studies of
Ro60
and Y RNAs in
Deinococcus radiodurans
, the first sequenced bacterium with a
Ro60
ortholog, revealed that they function with 3'-to-5' exoribonucleases to alter the composition of RNA populations during some forms of environmental stress. In the best-characterized example, Y RNA tethers the
Ro60
protein to the
exoribonuclease
polynucleotide phosphorylase, allowing this
exoribonuclease
to degrade structured RNAs more effectively. Y RNAs can also function as gates to regulate access of other RNAs to the
Ro60
central cavity. Recent studies in the enteric bacterium
Salmonella enterica
serovar Typhimurium resulted in the discovery that Y RNAs are widely present in bacteria. Remarkably, the most-conserved subclass of bacterial Y RNAs contains a domain that mimics tRNA. In this review, we discuss the structure, conservation, and known functions of bacterial Y RNAs as well as the certainty that more bacterial Y RNAs and additional roles for these ncRNAs remain to be uncovered.
...
PMID:Bacterial Y RNAs: Gates, Tethers, and tRNA Mimics. 3000 96
Noncoding Y RNAs are abundant in animal cells and present in many bacteria. These RNAs are bound and stabilized by
Ro60
, a ring-shaped protein that is a target of autoantibodies in patients with systemic lupus erythematosus. Studies in bacteria revealed that Y RNA tethers
Ro60
to a ring-shaped
exoribonuclease
, forming a double-ringed RNP machine specialized for structured RNA degradation. In addition to functioning as a tether, the bacterial RNA gates access of substrates to the
Ro60
cavity. To identify roles for Y RNAs in mammals, we used CRISPR to generate mouse embryonic stem cells lacking one or both of the two murine Y RNAs. Despite reports that animal cell Y RNAs are essential for DNA replication, cells lacking these RNAs divide normally. However,
Ro60
levels are reduced, revealing that Y RNA binding is required for
Ro60
to accumulate to wild-type levels. Y RNAs regulate the subcellular location of
Ro60
, since
Ro60
is reduced in the cytoplasm and increased in nucleoli when Y RNAs are absent. Last, we show that Y RNAs tether
Ro60
to diverse effector proteins to generate specialized RNPs. Together, our data demonstrate that the roles of Y RNAs are intimately connected to that of their
Ro60
partner.
...
PMID:Noncoding Y RNAs regulate the levels, subcellular distribution and protein interactions of their Ro60 autoantigen partner. 3246 55