Defects of the spliceosomal gene SNRPB affect osteo- and chondro-differentiation

SNRPB2: a prognostic biomarker and oncogenic driver in esophageal cancer via β-catenin/c-Myc signaling

Background

The SNRPB2 gene encodes Small Nuclear Ribonucleoprotein Polypeptide B2, a crucial component involved in RNA splicing processes. While SNRPB2 dysregulation has been observed in various cancers, its role in esophageal cancer (ESCA) remains unclear.

Methods

The mRNA level of SNRPB2 in ESCA was evaluated in combination with TCGA, GTEX, and GEO databases. The prognostic value of SNRPB2 was assessed using Kaplan-Meier analysis. Immunohistochemistry (IHC) was employed to confirm the expression of the SNRPB2 protein in tumor tissues from clinical samples. The biological functions of SNRPB2 were assessed in vitro cell assay and in vivo tumor models. The molecular mechanisms were determined by correlation and gene set enrichment analysis. Western blot experiments validated involvement in signaling pathways.

Results

Our findings unveiled that SNRPB2 was upregulated at both mRNA and protein levels in ESCA, which was associated with the pathological progression of the disease. Additionally, SNRPB2 served as a robust prognostic biomarker, implicated in driving oncogenic functions in ESCA. It facilitated cell proliferation, migration, and invasion, transitioned the cell cycle, and inhibited apoptosis. Mechanistically, SNRPB2 activated genes associated with the β-catenin/c-Myc signaling pathway, such as β-catenin, c-Myc, CCNA2, CCNB1, CDK1, and CDK2. This activation also regulated the epithelial-to-mesenchymal transition (EMT), thereby facilitating the progression of ESCA.

Conclusion

Our findings demonstrate that SNRPB2 contributes to ESCA progression by regulating the β-catenin/c-Myc axis, suggesting its potential as a prognostic biomarker and therapeutic target for ESCA patients.

Alternative pre-mRNA splicing in stem cell function and therapeutic potential: A critical review of current evidence

Alternative splicing is a crucial regulator in stem cell biology, intricately influencing the functions of various biological macromolecules, particularly pre-mRNAs and the resultant protein isoforms. This regulatory mechanism is vital in determining stem cell pluripotency, differentiation, and proliferation. Alternative splicing's role in allowing single genes to produce multiple protein isoforms facilitates the proteomic diversity that is essential for stem cells' functional complexity. This review delves into the critical impact of alternative splicing on cellular functions, focusing on its interaction with key macromolecules and how this affects cellular behavior. We critically examine how alternative splicing modulates the function and stability of pre-mRNAs, leading to diverse protein expressions that govern stem cell characteristics, including pluripotency, self-renewal, survival, proliferation, differentiation, aging, migration, somatic reprogramming, and genomic stability. Furthermore, the review discusses the therapeutic potential of targeting alternative splicing-related pathways in disease treatment, particularly focusing on the modulation of RNA and protein interactions. We address the challenges and future prospects in this field, underscoring the need for further exploration to unravel the complex interplay between alternative splicing, RNA, proteins, and stem cell behaviors, which is crucial for advancing our understanding and therapeutic approaches in regenerative medicine and disease treatment.

Bi-allelic loss-of-function variants in WBP4, encoding a spliceosome protein, result in a variable neurodevelopmental syndrome

Over two dozen spliceosome proteins are involved in human diseases, also referred to as spliceosomopathies. WW domain-binding protein 4 (WBP4) is part of the early spliceosomal complex and has not been previously associated with human pathologies in the Online Mendelian Inheritance in Man (OMIM) database. Through GeneMatcher, we identified ten individuals from eight families with a severe neurodevelopmental syndrome featuring variable manifestations. Clinical manifestations included hypotonia, global developmental delay, severe intellectual disability, brain abnormalities, musculoskeletal, and gastrointestinal abnormalities. Genetic analysis revealed five different homozygous loss-of-function variants in WBP4. Immunoblotting on fibroblasts from two affected individuals with different genetic variants demonstrated a complete loss of protein, and RNA sequencing analysis uncovered shared abnormal splicing patterns, including in genes associated with abnormalities of the nervous system, potentially underlying the phenotypes of the probands. We conclude that bi-allelic variants in WBP4 cause a developmental disorder with variable presentations, adding to the growing list of human spliceosomopathies.