Efficacy of nasal irrigation of normal saline as compared to budesonide following functional endoscopic sinus surgery

Background: Nasal irrigation following Functional endoscopic sinus surgery (FESS) appears to be a nearly universal recommendation. FESS significantly improves the symptoms of the CRS (Chronic rhino sinusitis) and the postoperative endoscopy scores. The primarily objective of our study was to study the efficacy of nasal irrigation of normal saline as compared to budesonide following functional endoscopic sinus surgery. Methods: A total of 100 patients who underwent functional endoscopic sinus surgery were randomly divided into two groups on the basis of computerized generated random table with 50 patients in each group. In group 1 normal saline was used where as in group 2 budesonide solution was used for nasal douching. Post-operative evaluation was done using Lund Kennedy Endoscopic scoring (LKES) at the 7th and 30th postoperative day. Results: On 7th postoperative day, we found that none of our patient in the study groups had polypoidal change. There was decrease in scores of polyposis, discharge mucosal edema, scaring and crusting in both the groups. However, the reduction of discharge in the budesonide group was more significantly decreased than normal saline group (p value<0.05). We also noted that  on 30th postoperative edema, scarring and crusting was significantly decreased in budesonide group as compared to normal saline group (p value <0.05). Conclusions: We concluded that the addition of budesonide in nasal irrigation resulted in improved scores of polyposis, discharge, mucosal edema, crusting and scarring and total score of LKES than normal saline alone

Expression of 24,426 human alternative splicing events and predicted cis regulation in 48 tissues and cell lines

partially because of the limited scale at which the expression of specific splicing events has been measured. We generated the first genome-scale expression compendium of human alternative splicing events using custom whole-transcript microarrays monitoring expression of 24,426 alternative splicing events in 48 diverse human samples. Over 11,700 genes and 9,500 splicing events were differentially expressed, providing a rich resource for studying splicing regulation. An unbiased, systematic screen of 21,760 4-mer to 7-mer words for cis-regulatory motifs identified 143 RNA 'words' enriched near regulated cassette exons, including six clusters of motifs represented by UCUCU, UGCAUG, UGCU, UGUGU, UUUU and AGGG, which map to trans-acting regulators PTB, Fox, Muscleblind, CELF/CUG-BP, TIA-1 and hnRNP F/H, respectively. Each cluster showed a distinct pattern of genomic location and tissue specificity. For example, UCUCU occurs 110 to 35 nucleotides preceding cassette exons upregulated in brain and striated muscle but depleted in other tissues. UCUCU and UGCAUG seem to have similar function but independent action, occurring 5' and 3', respectively, of 33% of the cassette exons upregulated in skeletal muscle but co-occurring for only 2%

Phosphoproteomics Screen Reveals Akt Isoform-Specific Signals Linking RNA Processing to Lung Cancer

The three Akt isoforms are functionally distinct. Here we show that their phosphoproteomes also differ, suggesting that their functional differences are due to differences in target specificity. One of the top cellular functions differentially regulated by Akt isoforms is RNA processing. IWS1, an RNA processing regulator, is phosphorylated by Akt3 and Akt1 at Ser720/Thr721. The latter is required for the recruitment of SETD2 to the RNA Pol II complex. SETD2 trimethylates histone H3 at K36 during transcription, creating a docking site for MRG15 and PTB. H3K36me3-bound MRG15 and PTB regulate FGFR-2 splicing, which controls tumor growth and invasiveness downstream of IWS1 phosphorylation. Twenty-one of the twenty-four non-small-cell-lung carcinomas we analyzed express IWS1. More importantly, the stoichiometry of IWS1 phosphorylation in these tumors correlates with the FGFR-2 splicing pattern and with Akt phosphorylation and Akt3 expression. These data identify an Akt isoform-dependent regulatory mechanism for RNA processing and demonstrate its role in lung cancer

Alternative splicing regulates vesicular trafficking genes in cardiomyocytes during postnatal heart development

During postnatal development the heart undergoes a rapid and dramatic transition to adult function through transcriptional and post-transcriptional mechanisms, including alternative splicing (AS). Here we perform deep RNA-sequencing on RNA from cardiomyocytes and cardiac fibroblasts to conduct a high-resolution analysis of transcriptome changes during postnatal mouse heart development. We reveal extensive changes in gene expression and AS that occur primarily between postnatal days 1 and 28. Cardiomyocytes and cardiac fibroblasts show reciprocal regulation of gene expression reflecting differences in proliferative capacity, cell adhesion functions and mitochondrial metabolism. We further demonstrate that AS plays a role in vesicular trafficking and membrane organization. These AS transitions are enriched among targets of two RNA-binding proteins, Celf1 and Mbnl1, which undergo developmentally regulated changes in expression. Vesicular trafficking genes affected by AS during normal development (when Celf1 is downregulated) show a reversion to neonatal splicing patterns after Celf1 re-expression in adults. Short-term Celf1 induction in adult animals results in disrupted transverse tubule organization and calcium handling. These results identify potential roles for AS in multiple aspects of postnatal heart maturation, including vesicular trafficking and intracellular membrane dynamics.Myotonic Dystrophy Foundation (Postdoctoral Fellowship

Expression of a Dominant Negative CELF Protein In Vivo Leads to Altered Muscle Organization, Fiber Size, and Subtype

CUG-BP and ETR-3-like factor (CELF) proteins regulate tissue- and developmental stage-specific alternative splicing in striated muscle. We previously demonstrated that heart muscle-specific expression of a nuclear dominant negative CELF protein in transgenic mice (MHC-CELFΔ) effectively disrupts endogenous CELF activity in the heart in vivo, resulting in impaired cardiac function. In this study, transgenic mice that express the dominant negative protein under a skeletal muscle-specific promoter (Myo-CELFΔ) were generated to investigate the role of CELF-mediated alternative splicing programs in normal skeletal muscle.Myo-CELFΔ mice exhibit modest changes in CELF-mediated alternative splicing in skeletal muscle, accompanied by a reduction of endomysial and perimysial spaces, an increase in fiber size variability, and an increase in slow twitch muscle fibers. Weight gain and mean body weight, total number of muscle fibers, and overall muscle strength were not affected.Although these findings demonstrate that CELF activity contributes to the normal alternative splicing of a subset of muscle transcripts in vivo, the mildness of the effects in Myo-CELFΔ muscles compared to those in MHC-CELFΔ hearts suggests CELF activity may be less determinative for alternative splicing in skeletal muscle than in heart muscle. Nonetheless, even these small changes in CELF-mediated splicing regulation were sufficient to alter muscle organization and muscle fiber properties affected in myotonic dystrophy. This lends further evidence to the hypothesis that dysregulation of CELF-mediated alternative splicing programs may be responsible for the disruption of these properties during muscle pathogenesis

Fenofibrate Reduces Mortality and Precludes Neurological Deficits in Survivors in Murine Model of Japanese Encephalitis Viral Infection

Background: Japanese encephalitis (JE), the most common form of viral encephalitis occurs periodically in endemic areas leading to high mortality and neurological deficits in survivors. It is caused by a flavivirus, Japanese encephalitis virus (JEV), which is transmitted to humans through mosquitoes. No effective cure exists for reducing mortality and morbidity caused by JEV infection, which is primarily due to excessive inflammatory response. Fenofibrate, a peroxisome proliferator-activated receptor-a (PPARa) agonist is known to resolve inflammation by repressing nuclear factor-kB (NF-kB) and enhancing transcription of anti-oxidant and anti-inflammatory genes. In addition, fenofibrate also up-regulates a class of proteins, cytochrome P4504Fs (Cyp4fs), which are involved in detoxification of the potent pro-inflammatory eicosanoid, leukotriene B4 (LTB4) to 20-hydroxy LTB4. Methodology/Principal Findings: The neuroprotective effect of fenofibrate was examined using in vitro (BV-2 microglial cell line) and in vivo (BALB/c mice) models of JEV infection. Mice were treated with fenofibrate for 2 or 4 days prior to JEV exposure. Pretreatment with fenofibrate for 4 but not 2 days reduced mortality by 80 % and brain LTB4 levels decreased concomitantly with the induction of Cyp4f15 and 4f18, which catalyze detoxification of LTB4 through hydroxylation. Expression of cytokines and chemokine decreased significantly as did microglial activation and replication of the JEV virus. Conclusions/Significance: Fenofibrate confers neuroprotection against Japanese encephalitis, in vivo, in mouse model o

Identification of MBNL1 and MBNL3 domains required for splicing activation and repression

Muscleblind-like 1 (MBNL1) is a splicing regulator that controls developmentally regulated alternative splicing of a large number of exons including exon 11 of the Insulin Receptor (IR) gene and exon 5 of the cardiac Troponin T (cTNT) gene. There are three paralogs of MBNL in humans, all of which promote IR exon 11 inclusion and cTNT exon 5 skipping. Here, we identify a cluster of three binding sequences located downstream of IR exon 11 that constitute the MBNL1 response element and a weaker response element in the upstream intron. In addition, we used sequential deletions to define the functional domains of MBNL1 and MBNL3. We demonstrate that the regions required for splicing regulation are separate from the two pairs of zinc-finger RNA-binding domains. MBNL1 and MBNL3 contain core regulatory regions for both activation and repression located within an 80-amino-acid segment located downstream of the N-terminal zinc-finger pair. Deletions of these regions abolished regulation without preventing RNA binding. These domains have common features with the CUG-BP and ETR3-like Factor (CELF) family of splicing regulators. These results have identified protein domains required for splicing repression and activation and provide insight into the mechanism of splicing regulation by MBNL proteins

CUGBP2 directly interacts with U2 17S snRNP components and promotes U2 snRNA binding to cardiac troponin T pre-mRNA

CUGBP2 (ETR-3/NAPOR/BRUNOL3) promotes inclusion of cardiac troponin T (cTNT) exon 5 via binding between positions 21 and 74 of the downstream intron. The molecular mechanism by which CUGBP2 activates cTNT exon 5 inclusion is unknown. Our results suggest that CUGBP2 promotes exon inclusion by a novel mechanism in which CUGBP2 directly interacts with components of the activated U2 snRNP and enhances binding of U2 snRNP to the branch site located upstream of the exon. Using an in vitro splicing assay, we show that recombinant CUGBP2 enhances complex A formation of a cTNT pre-mRNA. Enhanced complex A assembly requires both the upstream and downstream introns consistent with dual requirements for the downstream CUGBP2-binding site and an upstream branch site for U2 snRNP binding. We also show that CUGBP2 enhances binding of U2 snRNA to the cTNT pre-mRNA consistent with enhanced complex A assembly. Purification of CUGBP2-interacting proteins using tandem affinity purification leads to the demonstration that the core 17S U2 snRNP components, SF3b145 and SF3b49 bind directly to CUGBP2. We conclude that CUGBP2 activates exon inclusion by forming direct interactions with components of the 17S snRNP complex and recruits and/or stabilizes binding of U2 snRNP

Drosophila muscleblind Codes for Proteins with One and Two Tandem Zinc Finger Motifs

Muscleblind-like proteins, Muscleblind (Mbl) in Drosophila and MBNL1-3 in vertebrates, are regulators of alternative splicing. Human MBNL1 is a key factor in the etiology of myotonic dystrophy (DM), a muscle wasting disease caused by the occurrence of toxic RNA molecules containing CUG/CCUG repeats. MBNL1 binds to these RNAs and is sequestered in nuclear foci preventing it from exerting its normal function, which ultimately leads to mis-spliced mRNAs, a major cause of the disease. Muscleblind-proteins bind to RNAs via N-terminal zinc fingers of the Cys3-His type. These zinc fingers are arranged in one (invertebrates) or two (vertebrates) tandem zinc finger (TZF) motifs with both fingers targeting GC steps in the RNA molecule. Here I show that mbl genes in Drosophila and in other insects also encode proteins with two TZF motifs, highly similar to vertebrate MBNL proteins. In Drosophila the different protein isoforms have overlapping but possibly divergent functions in vivo, evident by their unequal capacities to rescue the splicing defects observed in mbl mutant embryos. In addition, using whole transcriptome analysis, I identified several new splicing targets for Mbl in Drosophila embryos. Two of these novel targets, kkv (krotzkopf-verkehrt, coding for Chitin Synthase 1) and cora (coracle, coding for the Drosophila homolog of Protein 4.1), are not muscle-specific but expressed mainly in epidermal cells, indicating a function for mbl not only in muscles and the nervous system