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Human genetic studies identified a strong association between loss of function mutations in RBFOX2 and hypoplastic left heart syndrome (HLHS). There are currently no Rbfox2 mouse models that recapitulate HLHS. Therefore, it is still unknown how RBFOX2 as an RNA binding protein contributes to heart development. To address this, we conditionally deleted Rbfox2 in embryonic mouse hearts and found profound defects in cardiac chamber and yolk sac vasculature formation. Importantly, our Rbfox2 conditional knockout mouse model recapitulated several molecular and phenotypic features of HLHS. To determine the molecular drivers of these cardiac defects, we performed RNA-sequencing in Rbfox2 mutant hearts and identified dysregulated alternative splicing (AS) networks that affect cell adhesion to extracellular matrix (ECM) mediated by Rho GTPases. We identified two Rho GTPase cycling genes as targets of RBFOX2. Modulating AS of these two genes using antisense oligos led to cell cycle and cell-ECM adhesion defects. Consistently, Rbfox2 mutant hearts displayed cell cycle defects and inability to undergo endocardial-mesenchymal transition, processes dependent on cell-ECM adhesion and that are seen in HLHS. Overall, our work not only revealed that loss of Rbfox2 leads to heart development defects resembling HLHS, but also identified RBFOX2-regulated AS networks that influence cell-ECM communication vital for heart development., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Chikungunya virus (CHIKV) is a mosquito-transmitted pathogen in family Togaviridae, genus Alphavirus. Although CHIKV is well known for its ability to cause debilitating rheumatoid-like arthritis, it has been also been observed to cause cardiovascular symptoms such as arrhythmias. Here, using samples from a previous study, we sequenced RNA from serum, kidney, skeletal muscle, and cardiac muscle from CHIKV- and mock-infected IFN-αR-/- mice using two sequencing techniques to investigate heart-specific changes in virus mutational profiles and host gene expression. Mutation rates were similar across muscle tissues although heart tissue carried heart-specific CHIKV minority variants, one of which had a coding change in the nsP3 gene and another in the 3'UTR. Importantly, heart-specific transcriptional changes included differential expression of genes critical for ion transport and muscle contraction. These results demonstrate that CHIKV replicates in the hearts of immunodeficient mice and induce heart-specific mutations and host responses with implications for cardiac pathologies.

RBFOX2, which has a well-established role in alternative splicing, is linked to heart diseases. However, it is unclear whether RBFOX2 has other roles in RNA processing that can influence gene expression in muscle cells, contributing to heart disease. Here, we employ both 3'-end and nanopore cDNA sequencing to reveal a previously unrecognized role for RBFOX2 in maintaining alternative polyadenylation (APA) signatures in myoblasts. RBFOX2-mediated APA modulates mRNA levels and/or isoform expression of a collection of genes, including contractile and mitochondrial genes. Depletion of RBFOX2 adversely affects mitochondrial health in myoblasts, correlating with disrupted APA of mitochondrial gene Slc25a4. Mechanistically, RBFOX2 regulation of Slc25a4 APA is mediated through consensus RBFOX2 binding motifs near the distal polyadenylation site, enforcing the use of the proximal polyadenylation site. In sum, our results unveil a role for RBFOX2 in fine-tuning expression of mitochondrial and contractile genes via APA in myoblasts relevant to heart diseases., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

High-throughput transcriptomics and proteomics approaches have recently identified a large number of germ cell-specific genes with many that remain to be studied through functional genetics approaches. Serine proteases (PRSS) constitute nearly one-third of all proteases, and, in our bioinformatics screens, we identified many that are testis specific. In this study, we chose to focus on Prss44, Prss46, and Prss54, which we confirmed as testis specific in mouse and human. Based on the analysis of developmental expression in the mouse, expression of all four genes is restricted to the late stage of spermatogenesis concomitant with a potential functional role in spermiogenesis, spermiation, or sperm function. To best understand the male reproductive requirement and functional roles of these serine proteases, each gene was individually ablated by CRISPR/Cas9-mediated ES cell or zygote approach. Homozygous deletion mutants for each gene were obtained and analyzed for phenotypic changes. Analyses of testis weights, testis and epididymis histology, sperm morphology, and fertility revealed no significant differences in Prss44, Prss46, and Prss54 knockout mice in comparison to controls. Our results thereby demonstrate that these genes are not required for normal fertility in mice, although do not preclude the possibility that these genes may function in a redundant manner. Elucidating the individual functional requirement or lack thereof of these novel genes is necessary to build a better understanding of the factors underlying spermatogenesis and sperm maturation, which has implications in understanding the etiology of male infertility and the development of male contraceptives., (© The Author(s) 2019. Published by Oxford University Press on behalf of Society for the Study of Reproduction.)

A consecutive sample of chronic pain patients presenting themselves for evaluation was studied. A set of 25 bi-polar adjectives was developed from medical records of previous pain patients' descriptions of their pain. Using the Semantic Differential (S-D) method, each patient rated the extent to which his/her pain was best described by either of the adjective pairs. The S-D findings were then compared with three other data sets and those data sets were compared with each other. First, six physicians classified each patient along an "organic"--"non-organic" continuum based on ratings derived from the full set of medical diagnostic labels each patient had accrued. Secondly, each patient, prior to examination, had completed up to two weeks of diary forms at home on which were recorded amount and distribution of time among sitting, standing/walking, and reclining. Finally, each patient completed a Minnesota Multiphasic Personality Inventory (MMPI). Few and only marginally significant relationships between patient semantic descriptions of their pain and the other measures were found. Secondly, physician agreement ot the "organic"--"non-organic" criterion, using diagnostic labels as their data, was statistically significant but clinically modest. The most substantial findings were between walking hours per week recorded on diary forms and five MMPI scales. Patients who walked more were less depressed, had fewer diffuse somatic complaints, and described themselves as less frustrated or angry and as less hypersensitive in interpersonal situations. The major conclusion of the study is that chronic pain patients present sets of interrelated problems too complex to be discriminated reliably by a single set of measures; particularly, by simple word sets.