Two Isoforms of the RNA Binding Protein, Coding Region Determinant-binding Protein (CRD-BP/IGF2BP1), Are Expressed in Breast Epithelium and Support Clonogenic Growth of Breast Tumor Cells

ABSTRACT Nonstructural protein 1 (nsp1), a 28-kDa protein in the bovine coronavirus (BCoV) and closely related mouse hepatitis coronavirus, is the first protein cleaved from the open reading frame 1 (ORF 1) polyprotein product of genome translation. Recently, a 30-nucleotide (nt) cis-replication stem-loop VI (SLVI) has been mapped at nt 101 to 130 within a 288-nt 5′-terminal segment of the 738-nt nsp1 cistron in a BCoV defective interfering (DI) RNA. Since a similar nsp1 coding region appears in all characterized groups 1 and 2 coronavirus DI RNAs and must be translated in cis for BCoV DI RNA replication, we hypothesized that nsp1 might regulate ORF 1 expression by binding this intra-nsp1 cistronic element. Here, we (i) establish by mutation analysis that the 72-nt intracistronic SLV immediately upstream of SLVI is also a DI RNA cis-replication signal, (ii) show by gel shift and UV-cross-linking analyses that cellular proteins of ∼60 and 100 kDa, but not viral proteins, bind SLV and SLVI, (SLV-VI) and (iii) demonstrate by gel shift analysis that nsp1 purified from Escherichia coli does not bind SLV-VI but does bind three 5′ untranslated region (UTR)- and one 3′ UTR-located cis-replication SLs. Notably, nsp1 specifically binds SLIII and its flanking sequences in the 5′ UTR with ∼2.5 μM affinity. Additionally, under conditions enabling expression of nsp1 from DI RNA-encoded subgenomic mRNA, DI RNA levels were greatly reduced, but there was only a slight transient reduction in viral RNA levels. These results together indicate that nsp1 is an RNA-binding protein that may function to regulate viral genome translation or replication but not by binding SLV-VI within its own coding region.

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The Protease Lon and the RNA-Binding Protein Hfq Reduce Silencing of the Escherichia coli bgl Operon by H-NS

Journal of Bacteriology ◽

10.1128/jb.186.9.2708-2716.2004 ◽

2004 ◽

Vol 186 (9) ◽

pp. 2708-2716 ◽

Cited By ~ 10

Author(s):

Sudhanshu Dole ◽

Yvonne Klingen ◽

V. Nagarajavel ◽

Karin Schnetz

Keyword(s):

Escherichia Coli ◽

Transcription Initiation ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Specific Effect ◽

Receptor Protein ◽

Coding Region ◽

Genes Encoding ◽

Pleiotropic Regulators

ABSTRACT The histone-like nucleoid structuring protein H-NS represses the Escherichia coli bgl operon at two levels. H-NS binds upstream of the promoter, represses transcription initiation, and binds downstream within the coding region of the first gene, where it induces polarity of transcription elongation. In hns mutants, silencing of the bgl operon is completely relieved. Various screens for mutants in which silencing of bgl is reduced have yielded mutations in hns and in genes encoding the transcription factors LeuO and BglJ. In order to identify additional factors that regulate bgl, we performed a transposon mutagenesis screen for mutants in which silencing of the operon is strengthened. This screen yielded mutants with mutations in cyaA, hfq, lon, and pgi, encoding adenylate cyclase, RNA-binding protein Hfq, protease Lon, and phosphoglucose isomerase, respectively. In cyaA mutants, the cyclic AMP receptor protein-dependent promoter is presumably inactive. The specific effect of the pgi mutants on bgl is low. Interestingly, in the hfq and lon mutants, the downstream silencing of bgl by H-NS (i.e., the induction of polarity) is more efficient, while the silencing of the promoter by H-NS is unaffected. Furthermore, in an hns mutant, Hfq has no significant effect and the effect of Lon is reduced. These data provide evidence that the specific repression by H-NS can (directly or indirectly) be modulated and controlled by other pleiotropic regulators.

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A Novel RNA-Binding Protein, Ossa/C9orf10, Regulates Activity of Src Kinases To Protect Cells from Oxidative Stress-Induced Apoptosis

Molecular and Cellular Biology ◽

10.1128/mcb.01035-08 ◽

2008 ◽

Vol 29 (2) ◽

pp. 402-413 ◽

Cited By ~ 21

Author(s):

Masamitsu Tanaka ◽

Kazuki Sasaki ◽

Reiko Kamata ◽

Yukari Hoshino ◽

Kazuyoshi Yanagihara ◽

...

Keyword(s):

Oxidative Stress ◽

Tumor Cells ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Pi3 Kinase ◽

Scaffolding Protein ◽

Functional Protein ◽

Uncharacterized Protein ◽

Induced Apoptosis

ABSTRACT During the process of tumor progression and clinical treatments, tumor cells are exposed to oxidative stress. Tumor cells are frequently resistant to such stress by producing antiapoptotic signaling, including activation of Src family kinases (SFKs), although the molecular mechanism is not clear. In an attempt to identify the SFK-binding proteins selectively phosphorylated in gastric scirrhous carcinoma, we identified an uncharacterized protein, C9orf10. Here we report that C9orf10 (designated Ossa for oxidative stress-associated Src activator) is a novel RNA-binding protein that guards cancer cells from oxidative stress-induced apoptosis by activation of SFKs. Exposure to oxidative stress such as UV irradiation induces the association of Ossa/C9orf10 with regulatory domains of SFKs, which activates these kinases and causes marked tyrosine phosphorylation of C9orf10 in turn. Tyrosine-phosphorylated Ossa recruits p85 subunits of phosphatidylinositol 3-kinase (PI3-kinase) and behaves as a scaffolding protein for PI3-kinase and SFKs, which activates the Akt-mediated antiapoptotic pathway. On the other hand, the carboxyl terminus of Ossa has a distinct function that directly binds RNAs such as insulin-like growth factor II (IGF-II) mRNA and promotes the extracellular secretion of IGF-II. Our findings indicate that Ossa is a dual-functional protein and might be a novel therapeutic target which modulates the sensitivity of tumors to oxidative stress.

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Global cataloguing of variations in untranslated regions of viral genome and prediction of key host RNA binding protein-microRNA interactions modulating genome stability in SARS-CoV2

10.1101/2020.06.09.134585 ◽

2020 ◽

Cited By ~ 3

Author(s):

Moumita Mukherjee ◽

Srikanta Goswami

Keyword(s):

Genome Stability ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Untranslated Regions ◽

Global Changes ◽

Sequence Information ◽

Coding Region ◽

High Coverage ◽

Geographical Regions

AbstractBackgroundThe world is going through the critical phase of COVID-19 pandemic, caused by human coronavirus, SARS-CoV2. Worldwide concerted effort to identify viral genomic changes across different sub-types has identified several strong changes in the coding region. However, there have not been many studies focusing on the variations in the 5’ and 3’ untranslated regions and their consequences. Considering the possible importance of these regions in host mediated regulation of viral RNA genome, we wanted to explore the phenomenon.MethodsTo have an idea of the global changes in 5’ and 3’-UTR sequences, we downloaded 8595 complete and high-coverage SARS-CoV2 genome sequence information from human host in FASTA format from Global Initiative on Sharing All Influenza Data (GISAID) from 15 different geographical regions. Next, we aligned them using Clustal Omega software and investigated the UTR variants. We also looked at the putative host RNA binding protein (RBP) and microRNA binding sites in these regions by ‘RBPmap’ and ‘RNA22 v2’ respectively. Expression status of selected RBPs and microRNAs were checked in lungs tissue.ResultsWe identified 28 unique variants in SARS-CoV2 UTR region based on a minimum variant percentage cut-off of 0.5. Along with 241C>T change the important 5’-UTR change identified was 187A>G, while 29734G>C, 29742G>A/T and 29774C>T were the most familiar variants of 3’UTR among most of the continents. Furthermore, we found that despite of the variations in the UTR regions, binding of host RBP to them remains mostly unaltered, which further influenced the functioning of specific miRNAs.ConclusionOur results, shows for the first time in SARS-Cov2 infection, a possible cross-talk between host RBPs-miRNAs and viral UTR variants, which ultimately could explain the mechanism of escaping host RNA decay machinery by the virus. The knowledge might be helpful in developing anti-viral compounds in future.

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