Family Of RNA-binding Proteins Research Articles

The interferon-induced protein, IFIT2, requires RNA-binding activity and neuronal expression to protect mice from intranasal vesicular stomatitis virus infection.

The interferon (IFN) system protects mammals from diseases caused by virus infections. IFN synthesis is induced by pattern recognition receptor signaling pathways activated by virus infection. IFN is secreted from the infected cells and acts upon neighboring cells by binding cell surface receptors and triggering induction of hundreds of IFN-stimulated genes and proteins, many of which block different steps of virus replication. The IFN-induced tetratricopeptide repeat proteins (IFIT) are a family of RNA-binding proteins. We and others have previously reported that IFIT2 protects mice from many neurotropic RNA viruses; indeed, Ifit2-/- mice are very susceptible to intranasal or subcutaneous infections with vesicular stomatitis virus (VSV). Here, using a newly generated conditional knockout mouse, we report that ablation of Ifit2 expression only in neuronal cells was sufficient to render mice susceptible to neuropathogenesis caused by intranasal, but not subcutaneous, infection of VSV. Another genetically modified mouse line, expressing a mutant IFIT2 that cannot bind RNA, was as susceptible to VSV infection as Ifit2-/- mice. These results demonstrated that IFIT2 RNA-binding activity is essential for protecting mice against neurological diseases caused by intranasal infection of VSV.IMPORTANCEInterferon's (IFN's) antiviral effects are mediated by the proteins encoded by the interferon-stimulated genes. IFN-stimulated genes (IFIT2) is one such protein, which inhibits replication of many RNA viruses in the mouse brain and the resultant neuropathology. Our study sheds light on how IFIT2 works. By ablating Ifit2 expression only in neuronal cells, using a newly generated conditional knockout mouse line, we showed that Ifit2 induction in the neurons of the infected mouse was necessary for antiviral function of interferon. IFIT2 has no known enzyme activity; instead, it functions by binding to cellular or viral proteins or RNAs. We engineered a new mouse line that expressed a mutant IFIT2 that cannot bind RNA. These mice were very susceptible to infection with vesicular stomatitis virus indicating that the RNA-binding property of IFIT2 was essential for its antiviral function in vivo.

Loss of CELF2 promotes skin tumorigenesis and increases drug resistance.

CELF2 belongs to the CELF RNA-binding protein family and exhibits antitumor activity in various tumor models. Analysis of the pan-cancer TCGA database reveals that CELF2 expression strongly correlates with favorable prognosis among cancer patients. The function of CELF2 in nonmelanoma skin cancer has not been studied. We used shRNA-mediated knockdown (KD) of CELF2 expression in human squamous cell carcinoma (SCC) cells to investigate how CELF2 impacted SCC cell proliferation, survival, and xenograft tumor growth. We determined CELF2 expression in human SCC tissues and adjacent normal skin using immunofluorescence staining. Additionally, we investigated the changes in CELF2 and its target gene expression during UV-induced and chemical-induced skin tumorigenesis by western blotting. CELF2 KD significantly increased SCC cell proliferation, colony growth, and SCC xenograft tumor growth in immunodeficient mice. CELF2 KD in SCC cells led to activation of KRT80 and GDF15, which can potentially promote cell proliferation and tumor growth. While control SCC cells were sensitive to anticancer drugs such as doxorubicin, SCC cells with CELF2 KD became resistant to drug-induced tumor growth retardation. Finally, we found CELF2 expression diminished during both UV- and chemical-induced skin tumorigenesis in mice, consistent with reduced CELF2 expression in human SCC tumors compared to adjacent normal skin. This study shows for the first time that CELF2 loss occurs during skin tumorigenesis and increases drug resistance in SCC cells, highlighting the possibility of targeting CELF2-regulated pathways in skin cancer prevention and therapies.

Liver cancer initiation requires translational activation by an oncofetal regulon involving LIN28 proteins.

It is unknown which posttranscriptional regulatory mechanisms are required for oncogenic competence. Here, we show that the LIN28 family of RNA-binding proteins (RBPs), which facilitate posttranscriptional RNA metabolism within ribonucleoprotein networks, is essential for the initiation of diverse oncotypes of hepatocellular carcinoma (HCC). In HCC models driven by NRASG12V/Tp53, CTNNB1/YAP/Tp53, or AKT/Tp53, mice without Lin28a and Lin28b were markedly impaired in cancer initiation. We biochemically defined an oncofetal regulon of 15 factors connected to LIN28 through direct mRNA and protein interactions. Interestingly, all were RBPs and only 1 of 15 was a Let-7 target. Polysome profiling and reporter assays showed that LIN28B directly increased the translation of 8 of these 15 RBPs. As expected, overexpression of LIN28B and IGFBP1-3 was able to genetically rescue cancer initiation. Using this platform to probe components downstream of LIN28, we found that 8 target RBPs were able to restore NRASG12V/Tp53 cancer formation in Lin28a/Lin28b-deficient mice. Furthermore, these LIN28B targets promote cancer initiation through an increase in protein synthesis. LIN28B, central to an RNP regulon that increases translation of RBPs, is important for tumor initiation in the liver.

Interferon-Regulated Expression of Cellular Splicing Factors Modulates Multiple Levels of HIV-1 Gene Expression and Replication.

Type I interferons (IFN-Is) are pivotal in innate immunity against human immunodeficiency virus I (HIV-1) by eliciting the expression of IFN-stimulated genes (ISGs), which encompass potent host restriction factors. While ISGs restrict the viral replication within the host cell by targeting various stages of the viral life cycle, the lesser-known IFN-repressed genes (IRepGs), including RNA-binding proteins (RBPs), affect the viral replication by altering the expression of the host dependency factors that are essential for efficient HIV-1 gene expression. Both the host restriction and dependency factors determine the viral replication efficiency; however, the understanding of the IRepGs implicated in HIV-1 infection remains greatly limited at present. This review provides a comprehensive overview of the current understanding regarding the impact of the RNA-binding protein families, specifically the two families of splicing-associated proteins SRSF and hnRNP, on HIV-1 gene expression and viral replication. Since the recent findings show specifically that SRSF1 and hnRNP A0 are regulated by IFN-I in various cell lines and primary cells, including intestinal lamina propria mononuclear cells (LPMCs) and peripheral blood mononuclear cells (PBMCs), we particularly discuss their role in the context of the innate immunity affecting HIV-1 replication.

Guanine-Rich RNA Sequence Binding Factor 1 Deficiency Promotes Colorectal Cancer Progression by Regulating PI3K/AKT Signaling Pathway.

Guanine-rich RNA sequence binding factor 1 (GRSF1), part of the RNA-binding protein family, is now attracting interest due to its potential association with the progression of a variety of human cancers. The precise contribution and molecular mechanism of GRSF1 to colorectal cancer (CRC) progression, however, have yet to be clarified. Immunohistochemistry and Western Blot analysis was carried out to detect the expression of GRSF1 in CRC at both mRNA and protein levels and its subsequent effects on prognosis. A series of functional tests were performed to understand its influence on proliferation, migration, and invasion of CRC cells. The universal downregulation of GRSF1 in CRC was identified, indicating a correlation with poor prognosis. Our functional studies unveiled that the elimination of GRSF1 enhances tumour activities such as proliferation, migration, and invasion of CRC cells, while GRSF1 overexpression curtailed these abilities. Notably, we uncovered that GRSF1 insufficiency modulates the PI3K/Akt signaling pathway and Ras activation in CRC. Therefore, our data suggest GRSF1 operates as a tumor suppressor gene in CRC and may offer promise as a potential biomarker and novel therapeutic target in CRC management.

Musashi-2 induces cardiac hypertrophy and heart failure by inducing mitochondrial dysfunction through destabilizing cluh and smyd1 mRNA

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work is funded by Ramalingaswami Re-entry Fellowship (BT/RLF/re-entry/14/2019) from the Department of Biotechnology, Government of India Background Regulation of RNA stability and translation by RNA-binding proteins (RBPs) is a crucial process altering gene expression. Musashi family of RBPs comprising Msi1 and Msi2 are known to control RNA stability and translation with a well-characterized role in the hematopoietic system, gut and cancer. However, the functions of Musashi in the heart is not explored. Purpose Despite the expression of MSI2 in the heart, its role remains largely unknown. In our study, we endeavor to understand the cardiac function of MSI2. Methods RNA-seq analysis, adeno-associated virus (AAV), lentivirus, echocardiography, histopathology, proteomics, electron microscopy, luciferase assay, ROS measurement, TMRE red staining, seahorse assay, MSI2 pooldown, and H3K4me3 ChIP assay were used to elucidate the function of Msi2 in cardiomyocytes. Results Among the two Musashi members, the heart expresses only Msi2. We confirmed the presence of MSI2 in the adult mouse, rat heart, and neonatal rat cardiomyocytes. Furthermore, Msi2 is significantly enriched in the heart cardiomyocytee fraction. Next, using RNA-seq data and isoform-specific PCR primers, we identified Msi2 isoforms 1, 4 and 5, and two novel putative isoforms labeled as Msi2 6 and 7 to be expressed in the heart. Overexpression of Msi2 isoforms led to cardiac hypertrophy in cultured cardiomyocytes. Additionally, Msi2 exhibited a significant increase in a pressure-overload model of cardiac hypertrophy. We selected isoforms 4 and 7 to validate the hypertrophic effects due to their unique alternative splicing patterns. AAV9-mediated overexpression of Msi2 isoforms 4 and 7 in murine hearts led to cardiac hypertrophy, dilation, heart failure,and eventually early death, confirming a pathological function for Msi2. Using global proteomics, gene ontology, transmission electron microscopy, seahorse, and transmembrane potential measurement assys, increased MSI2 was found to cause mitochondrial dysfunction in the heart. Mechanistically, we identified Cluh and Smyd1 as direct downstream target of Msi2. Overexpression of Cluh and Smyd1 inhbited Msi2-induced cardiac mitochondrial dysfunction. Collectively, we show that Msi2 inducs hypertrophy, mitochondrial dysfunction, and heart failure. Conclusion We here show that Msi2 has a pro-hypertrophic function in cardiomyocytes leading to heart failure and death in mice. AAV9 mediated overexpression of Msi2 promoted degradation of Cluh and Smyd1 and thus led to mitochondrial dysfunction. Overexpression of Cluh and Smyd1 inhibits the pro-hypertrophic and mitochondrial dysfunction induced by Msi2.

Genome-Wide Identification and Expression Analysis of the YTH Domain-Containing RNA-Binding Protein Family in Cinnamomum camphora.

N6-methyladenosine (m6A) is one of the most abundant chemical modifications on mRNA in eukaryotes. RNA-binding proteins containing the YT521-B (YTH) domain play crucial roles in post-transcriptional regulation of plant growth, development, and stress response by reading the m6A mark. However, the YTH domain-containing RNA-binding protein family has not been studied in a valuable and medicinal tree such as Cinnamomum camphora (C. camphora) yet. In this study, we identified 10 YTH genes in C. camphora, located on eight out of 12 chromosomes. Phylogenetic analysis revealed that these genes can be classified into two major classes, YTHDF (CcDF) and YTHDC (CcDC). Closely related CcYTHs within the same class exhibited a similar distribution of conserved motifs and domain organization, suggesting functional similarities among these closely related CcYTHs. All CcYTH proteins possessed a highly conserved YTH domain, with CcDC1A containing an additional CCCH domain. The liquid-liquid phase separation (LLPS) predictions indicate that CcDC1A, CcDF1A, CcDF1C, CcDF3C, CcDF4C, and CcDF5C may undergo phase transitions. Quantitative expression analysis revealed that tissue-specific expression was observed fo CcYTHs. Notably, there were two genes, CcDF1A and CcDF5C; both exhibited significantly higher expression levels in various tissues than other genes, indicating that the m6A-YTH regulatory network in C. camphora might be quite distinct from that in most plants such as Arabidopsis thaliana (A. thaliana) with only one abundant YTH protein. According to the analysis of the up-stream cis-regulatory elements of these YTH genes, these genes could be closely related to stress, hormones, and development. The following stress response experiments further verified that their expression levels indeed changed under both PEG and NaCl treatments. These findings not only provide a foundation for future functional analysis of CcYTHs in C. camphora, but also provide insights into the functions of epigenetic mark m6A in forest trees.

Bioinformatic Analysis of Roquin Family Reveals Their Potential Role in Immune System.

The Roquin family is a recognized RNA-binding protein family that plays vital roles in regulating the expression of pro-inflammatory target gene mRNA during the immune process in mammals. However, the evolutionary status of the Roquin family across metazoans remains elusive, and limited studies are found in fish species. In this study, we discovered that the RC3H genes underwent a single round of gene duplication from a primitive ancestor during evolution from invertebrates to vertebrates. Furthermore, there were instances of species-specific gene loss events or teleost lineage-specific gene duplications throughout evolution. Domain/motif organization and selective pressure analysis revealed that Roquins exhibit high homology both within members of the family within the same species and across species. The three rc3h genes in zebrafish displayed similar expression patterns in early embryos and adult tissues, with rc3h1b showing the most prominent expression among them. Additionally, the promoter regions of the zebrafish rc3h genes contained numerous transcription factor binding sites similar to those of mammalian homologs. Moreover, the interaction protein network of Roquin and the potential binding motif in the 3'-UTR of putative target genes analysis both indicated that Roquins have the potential to degrade target mRNA through mechanisms similar to those of mammalian homologs. These findings shed light on the evolutionary history of Roquin among metazoans and hypothesized their role in the immune systems of zebrafish.

ADR-2 regulates fertility and oocyte fate in C. elegans.

RNA binding proteins play essential roles in coordinating germline gene expression and development in all organisms. Here, we report that loss of ADR-2, a member of the Adenosine DeAminase acting on RNA (ADAR) family of RNA binding proteins and the sole adenosine-to-inosine RNA editing enzyme in C. elegans, can improve fertility in multiple genetic backgrounds. First, we show that loss of RNA editing by ADR-2 restores normal embryo production to subfertile animals that transgenically express a vitellogenin (yolk protein) fusion to green fluorescent protein. Using this phenotype, a high-throughput screen was designed to identify RNA binding proteins that when depleted yield synthetic phenotypes with loss of adr-2. The screen uncovered a genetic interaction between ADR-2 and SQD-1, a member of the heterogenous nuclear ribonucleoprotein (hnRNP) family of RNA binding proteins. Microscopy, reproductive assays, and high-throughput sequencing reveal that sqd-1 is essential for the onset of oogenesis and oogenic gene expression in young adult animals, and that loss of adr-2 can counteract the effects of loss of sqd-1 on gene expression and rescue the switch from spermatogenesis to oogenesis. Together, these data demonstrate that ADR-2 can contribute to the suppression of fertility and suggest novel roles for both RNA editing-dependent and independent mechanisms in regulating embryogenesis.

YTHDF1 is pivotal for maintenance of cardiac homeostasis

The YTH-domain family (YTHDF) of RNA binding proteins can control gene expression at the post-transcriptional level by regulating mRNAs with N6-methyladenosine (m6A) modifications. Despite the established importance of m6A in the heart, the cardiac role of specific m6A-binding proteins remains unclear. Here, we characterized the function of YTHDF1 in cardiomyocytes using a newly generated cardiac-restricted mouse model. Deletion of YTHDF1 in adult cardiomyocytes led to hypertrophy, fibrosis, and dysfunction. Using mass spectrometry, we identified the necessity of YTHDF1 for the expression of cardiomyocyte membrane raft proteins. Specifically, YTHDF1 bound to m6A-modified Caveolin 1 (Cav1) mRNA and favored its translation. We further demonstrated that YTHDF1 regulates downstream ERK signaling. Altogether, our findings highlight a novel role for YTHDF1 as a post-transcriptional regulator of caveolar proteins which is necessary for the maintenance of cardiac function.

Tomato (Solanum lycopersicum L.) YTH Domain-Containing RNA-Binding Protein (YTP) Family Members Participate in Low-Temperature Treatment and Waterlogging Stress Responses

YT521-B homology (YTH) domain-containing RNA-binding proteins (YTPs) are important N6-methyladenosine (m6A) readers that have crucial roles in determining the destiny of m6A-modified RNAs, which are the most widespread RNA modifications in eukaryotes. Tomatoes (Solanum lycopersicum L.) hold significant importance in both dietary consumption patterns and scientific inquiries. While the YTP gene family has been characterized in tomatoes, their specific reactions to the low temperature and waterlogging stresses remain to be elucidated. In our study, nine tomato SlYTPs could be divided into five subclasses, YTHDFa-c and YTHDCa-b. After gene cloning and measuring their expression levels under stress conditions, it was revealed that SlYTP8 exhibited increased sensitivity to low-temperature treatment, while the expression levels of SlYTP9 were notably upregulated in leaf tissues subjected to waterlogging conditions. As members of the YTHDFc subfamily, SlYTP8 and SlYTP9 are both localized in the cytoplasm. Nevertheless, overexpression (OE) of SlYTP8 increased the sensitivity of tomato plants to low-temperature treatment, which was manifested by a higher accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and a weaker reactive oxygen species scavenging ability compared to wild-type (WT) tomatoes. However, in comparison to WT plants, the leaves of SlYTP9 OE tomatoes showed higher chlorophyll content and a stronger reactive oxygen species scavenging ability after 3 days of waterlogging treatment, thereby increasing the resistance of tomatoes to waterlogging stress. Moreover, in order to investigate the possible molecular mechanisms underlying their responses to the low temperature and waterlogging stresses, the transcription factors and interacting protein networks associated with SlYTP8/9 promoters and proteins were also predicted, respectively. These results could fill the gap in the understanding of tomato YTPs in response to the low temperature and waterlogging stresses, while also providing a theoretical and experimental basis for subsequent studies on their molecular mechanisms.

Heterogeneous nuclear ribonucleoprotein A3 binds to the internal ribosomal entry site of enterovirus A71 and affects virus replication in neural cells.

Enterovirus A71 (EV-A71) belongs to the genus Enterovirus of the Picornaviridae family and often causes outbreaks in Asia. EV-A71 infection usually causes hand, foot, and mouth disease and can even affect the central nervous system, causing neurological complications or death. The 5'-untranslated region (5'-UTR) of EV-A71 contains an internal ribosome entry site (IRES) that is responsible for the translation of viral proteins. IRES-transacting factors can interact with the EV-A71 5'-UTR to regulate IRES activity. Heterogeneous nuclear ribonucleoprotein (hnRNP) A3 is a member of the hnRNP A/B protein family of RNA-binding proteins and is involved in RNA transport and modification. We found that hnRNP A3 knockdown promoted the replication of EV-A71 in neural calls. Conversely, increasing the expression of hnRNP A3 within cells inhibits the growth of EV-A71. HnRNP A3 can bind to the EV-A71 5'-UTR, and knockdown of hnRNP A3 enhances the luciferase activity of the EV-A71 5'-UTR IRES. The localization of hnRNP A3 shifts from the nucleus to the cytoplasm of infected cells during viral infection. Additionally, EV-A71 infection can increase the protein expression of hnRNP A3, and the protein level is correlated with efficient viral growth. Based on these findings, we concluded that hnRNP A3 plays a negative regulatory role in EV-A71 replication within neural cells.

The RNA binding protein EHD6 recruits the m6A reader YTH07 and sequesters OsCOL4 mRNA into phase-separated ribonucleoprotein condensates to promote rice flowering

N6-Methyladenosine (m6A) is one of the most abundant modifications of eukaryotic mRNA, but its comprehensive biological functionality remains further exploration. In this study, we identified and characterized a new flowering-promoting gene, EARLY HEADING DATE6 (EHD6), in rice. EHD6 encodes an RNA recognition motif (RRM)-containing RNA binding protein that is localized in the non-membranous cytoplasm ribonucleoprotein (RNP) granules and can bind both m6A-modified RNA and unmodified RNA indiscriminately. We found that EHD6 can physically interact with YTH07, a YTH (YT521-B homology) domain-containing m6A reader. We showed that their interaction enhances the binding of an m6A-modified RNA and triggers relocation of a portion of YTH07 from the cytoplasm into RNP granules through phase-separated condensation. Within these condensates, the mRNA of a rice flowering repressor, CONSTANS-like 4 (OsCOL4), becomes sequestered, leading to a reduction in its protein abundance and thus accelerated flowering through the Early heading date 1 pathway. Taken together, these results not only shed new light on the molecular mechanism of efficient m6A recognition by the collaboration between an RNA binding protein and YTH family m6A reader, but also uncover the potential for m6A-mediated translation regulation through phase-separated ribonucleoprotein condensation in rice.

Abstract 162: Post-transcriptional Regulation Of FGF21 In Obesity And Metabolism

Imbalances in energy intake and expenditure are the leading cause of the dramatic surge in obesity and cardiovascular disease affecting >60% of Americans. Increasing fat content in the average diet alters metabolism and contributes to disease. FGF21, a secreted hepatokine, modulates feeding behavior and energy expenditure (EE) primarily through signaling in brain and adipose tissue. FGF21 analogues are actively in clinical trials for several metabolic diseases, and it is therefore important to understand the various pathways that control FGF21. FGF21 is regulated by well-defined transcriptional programs, but its post-transcriptional regulation is less understood. Post-transcriptional regulation is mediated by RNA binding proteins (RBPs) that control mRNA stability. One family of such RBPs is the ZFP36 family proteins (ZFP36, ZFP36L1, ZFP36L2) that bind to AU-rich regions in the 3’UTR, leading to mRNA degradation. All 3 ZFP36 family proteins are redundant, therefore we knocked out Zfp36 , Zfp36l1 and Zfp36l2 in livers of adult mice. Fgf21 was the most upregulated gene following loss of ZFP36 family proteins in the liver. Consistent with elevated FGF21, these mice rapidly lost weight and fat mass while remaining metabolically healthy. Using metabolic cages, we observed that mice lacking hepatic ZFP36 family proteins had increased food intake and EE and decreased respiratory exchange ratio, indicating preferential fat burning. We then generated mice lacking the ZFP36 family proteins and Fgf21 which partially restored the metabolic phenotypes observed, leading to the hypothesis that ZFP36 family proteins post-transcriptionally regulate Fgf21 in controlling food intake and energy homeostasis. To determine if loss of ZFP36 family proteins protects against diet-induced obesity, we fed mice lacking the ZFP36 family proteins a high fat diet, however, they were entirely protected from diet induced obesity. The protection was partially reversed by additional deletion of Fgf21 . These findings demonstrate that FGF21 is regulated post-transcriptionally by the ZFP36 family proteins and loss of this mode of regulation has significant metabolic implications in diet-induced obesity and could lead to new therapeutic approaches to treat metabolic disease.

Bruno 1/CELF regulates splicing and cytoskeleton dynamics to ensure correct sarcomere assembly in Drosophila flight muscles.

Muscles undergo developmental transitions in gene expression and alternative splicing that are necessary to refine sarcomere structure and contractility. CUG-BP and ETR-3-like (CELF) family RNA-binding proteins are important regulators of RNA processing during myogenesis that are misregulated in diseases such as Myotonic Dystrophy Type I (DM1). Here, we report a conserved function for Bruno 1 (Bru1, Arrest), a CELF1/2 family homolog in Drosophila, during early muscle myogenesis. Loss of Bru1 in flight muscles results in disorganization of the actin cytoskeleton leading to aberrant myofiber compaction and defects in pre-myofibril formation. Temporally restricted rescue and RNAi knockdown demonstrate that early cytoskeletal defects interfere with subsequent steps in sarcomere growth and maturation. Early defects are distinct from a later requirement for bru1 to regulate sarcomere assembly dynamics during myofiber maturation. We identify an imbalance in growth in sarcomere length and width during later stages of development as the mechanism driving abnormal radial growth, myofibril fusion, and the formation of hollow myofibrils in bru1 mutant muscle. Molecularly, we characterize a genome-wide transition from immature to mature sarcomere gene isoform expression in flight muscle development that is blocked in bru1 mutants. We further demonstrate that temporally restricted Bru1 rescue can partially alleviate hypercontraction in late pupal and adult stages, but it cannot restore myofiber function or correct structural deficits. Our results reveal the conserved nature of CELF function in regulating cytoskeletal dynamics in muscle development and demonstrate that defective RNA processing due to misexpression of CELF proteins causes wide-reaching structural defects and progressive malfunction of affected muscles that cannot be rescued by late-stage gene replacement.

A guide to selecting high-performing antibodies for RNA-binding protein TIA1 for use in Western Blot, immunoprecipitation and immunofluorescence.

A member of the RNA-binding protein family, T-cell intracellular antigen-1 (TIA1) regulates mRNA translation and splicing as well as cellular stress by promoting stress granule formation. Variants of the TIA1 gene have implications in neurogenerative disorders including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Reproducible research on TIA1 would be enhanced with the availability of high-quality anti-TIA1 antibodies. In this study, we characterized twelve TIA1 commercial antibodies for Western Blot, immunoprecipitation, and immunofluorescence using a standardized experimental protocol based on comparing read-outs in knockout cell lines and isogenic parental controls. We identified many high-performing antibodies and encourage readers to use this report as a guide to select the most appropriate antibody for their specific needs.

Bibliometric Overview on T-Cell Intracellular Antigens and Their Pathological Implications.

T-cell intracellular antigen 1 (TIA1) and TIA1-like/related protein (TIAL1/TIAR) are two members of the classical family of RNA binding proteins. Through their selective interactions with distinct RNAs and proteins, these multifunctional regulators are involved in chromatin remodeling, RNA splicing and processing and translation regulation, linking them to a wide range of diseases including neuronal disorders, cancer and other pathologies. From their discovery to the present day, many studies have focused on the behavior of these proteins in order to understand their impact on molecular and cellular processes and to understand their relationship to human pathologies. The volume of research on these proteins in various fields, including molecular biology, biochemistry, cell biology, immunology and cancer, has steadily increased, indicating a growing interest in these gene expression regulators among researchers. This information can be used to know the most productive institutions working in the field, understand the focus of research, identify key areas of involvement, delve deeper into their relationship and impact on different diseases, and to establish the level of study associated with them.

Human antigen R: Exploring its inflammatory response impact and significance in cardiometabolic disorders.

RNA-binding proteins (RBPs) play a crucial role in the regulation of posttranscriptional RNA networks, which can undergo dysregulation in many pathological conditions. Human antigen R (HuR) is a highly researched RBP that plays a crucial role as a posttranscriptional regulator. HuR plays a crucial role in the amplification of inflammatory signals by stabilizing the messenger RNAof diverse inflammatory mediators and key molecular players. The noteworthy correlations between HuR and its target molecules, coupled with the remarkable impacts reported on the pathogenesis and advancement of multiple diseases, position HuR as a promising candidate for therapeutic intervention in diverse inflammatory conditions. This review article examines the significance of HuR as a member of the RBP family, its regulatory mechanisms, and its implications in the pathophysiology of inflammation and cardiometabolic illnesses. Our objective is to illuminate potential directions for future research and drug development by conducting a comprehensive analysis of the existing body of research on HuR.

Studying the Effect of MBNL1 and MBNL2 Loss in Skeletal Muscle Regeneration.

Loss of function of members of the muscleblind-like (MBNL) family of RNA binding proteins has been shown to play a key role in the spliceopathy of RNA toxicity in myotonic dystrophy type 1 (DM1), the most common muscular dystrophy affecting adults and children. MBNL1 and MBNL2 are the most abundantly expressed members in skeletal muscle. A key aspect of DM1 is poor muscle regeneration and repair, leading to dystrophy. We used a BaCl2-induced damage model of muscle injury to study regeneration and effects on skeletal muscle satellite cells (MuSCs) in Mbnl1∆E3/∆E3 and Mbnl2∆E2/∆E2 knockout mice. Similar experiments have previously shown deleterious effects on these parameters in mouse models of RNA toxicity. Muscle regeneration in Mbnl1 and Mbnl2 knockout mice progressed normally with no obvious deleterious effects on MuSC numbers or increased expression of markers of fibrosis. Skeletal muscles in Mbnl1∆E3/∆E3/ Mbnl2∆E2/+ mice showed increased histopathology but no deleterious reductions in MuSC numbers and only a slight increase in collagen deposition. These results suggest that factors beyond the loss of MBNL1/MBNL2 and the associated spliceopathy are likely to play a key role in the defects in skeletal muscle regeneration and deleterious effects on MuSCs that are seen in mouse models of RNA toxicity due to expanded CUG repeats.

ADARs regulate cuticle collagen expression and promote survival to pathogen infection

BackgroundIn all organisms, the innate immune system defends against pathogens through basal expression of molecules that provide critical barriers to invasion and inducible expression of effectors that combat infection. The adenosine deaminase that act on RNA (ADAR) family of RNA-binding proteins has been reported to influence innate immunity in metazoans. However, studies on the susceptibility of ADAR mutant animals to infection are largely lacking.ResultsHere, by analyzing adr-1 and adr-2 null mutants in well-established slow-killing assays, we find that both Caenorhabditis elegans ADARs are important for organismal survival to gram-negative and gram-positive bacteria, all of which are pathogenic to humans. Furthermore, our high-throughput sequencing and genetic analysis reveal that ADR-1 and ADR-2 function in the same pathway to regulate collagen expression. Consistent with this finding, our scanning electron microscopy studies indicate adr-1;adr-2 mutant animals also have altered cuticle morphology prior to pathogen exposure.ConclusionsOur data uncover a critical role of the C. elegans ADAR family of RNA-binding proteins in promoting cuticular collagen expression, which represents a new post-transcriptional regulatory node that influences the extracellular matrix. In addition, we provide the first evidence that ADAR mutant animals have altered susceptibility to infection with several opportunistic human pathogens, suggesting a broader role of ADARs in altering physical barriers to infection to influence innate immunity.