Integrative multiomic analysis reveals co-ordinated alternative splicing in human bone marrow stromal stem cells.

Area of Science:

• Molecular Biology
• Cell Biology
• Genomics

Background:

• Alternative splicing generates mRNA diversity from single genes, but its role in osteoblast differentiation is not fully understood.
• Mesenchymal stromal cells (MSCs) are multipotent stem cells that can differentiate into various cell types, including osteoblasts, which are crucial for bone formation.

Purpose of the Study:

• To investigate the comprehensive landscape of alternative splicing during human MSC differentiation into osteoblasts.
• To identify key genes and pathways regulated by alternative splicing during osteoblastogenesis.

Main Methods:

• Deep RNA sequencing (short- and long-read) was performed on differentiating hMSC-TERT4 cells.
• Proteomic and phosphoproteomic analyses were employed to complement transcriptomic data.

Main Results:

• Extensive alternative splicing changes were observed during lineage commitment, affecting genes with known transcriptional regulators (e.g., RUNX2, TEAD1).
• During osteoblast maturation, splicing alterations occurred in genes encoding cytoskeletal, extracellular matrix, and Golgi trafficking proteins.
• Proteomic data confirmed alternative splicing in proteins involved in RNA splicing, autophagy, and other cellular processes.

Conclusions:

• Alternative splicing plays an integrated role throughout the multiphasic osteoblast differentiation program.
• The study provides a detailed transcriptomic and proteomic view of splicing dynamics during MSC osteogenic differentiation.
• Understanding these splicing events offers insights into the regulation of bone formation and potential therapeutic targets.