Author Type

Graduate Student

Date of Award

Spring 4-3-2026

Document Type

Dissertation

Publication Status

Version of Record

Submission Date

April 2026

Department

Biological Sciences

College Granting Degree

Charles E. Schmidt College of Science

Department Granting Degree

Biology

Degree Name

Doctor of Philosophy (PhD)

Thesis/Dissertation Advisor [Chair]

Massimo Caputi

Abstract

Serine/Arginine splicing factor 1 (SRSF1) is an RNA-binding protein (RBP) that serves as a central regulator of RNA biogenesis. SRSF1 has been implicated in cell replication, motility, ageing, immune function, and other physiological processes, while its dysregulation is associated with multiple cancers and autoimmune diseases. In this study, we characterized the global impact and structural requirements of SRSF1-mediated gene regulation to elucidate its proto-oncogenic functions.

Utilizing a time-course RNA sequencing (RNA-seq) approach in HEK293 cells, we identified 28 primary transcriptional targets of SRSF1, 18 of which were consistently upregulated in the established cancer cell models PC-3 and MCF-7. These targets form a functional cluster associated with cytoskeletal organization, vascular remodeling, and immune modulation, suggesting that SRSF1 coordinates transcriptional programs that directly shape tumor behavior.

In parallel, RNA-seq analysis identified 603 alternative splicing events across 441 genes, including 418 protein-coding genes, enriched in pathways governing DNA repair, replication, and cell-cycle control. Experimental validation confirmed 67 of 140 analyzed events (64 genes), each showing a distinctive switch in alternative splicing following SRSF1 overexpression. Comparative analysis across HEK293, PC-3, and MCF-7 cells identified 35 conserved splicing events in 33 genes, 16 of which are involved in p53 regulation. SRSF1-induced splicing frequently generated isoforms predicted to undergo nonsense-mediated decay or encode truncated proteins, collectively attenuating p53-dependent transcriptional responses. Collectively, these alterations suggest that SRSF1 rewires the p53 regulatory network through a coordinated “push–pull” mechanism. On one hand, certain splice switches may promote p53 stabilization by increasing replication stress and reducing inhibitory control. On the other hand, additional splicing alterations impair key components of DNA damage checkpoint signaling and the transcriptional machinery required for effective p53 responses, ultimately promoting genomic instability and oncogenesis. Consistent with this model, SRSF1 overexpression was associated with replication stress, impaired checkpoint signaling, and increased proliferative capacity, reflecting a functional uncoupling of cell-cycle progression from genome maintenance. Mechanistically, this phenotype arises from the combined transcriptional activation of pro-survival pathways and the splicing-mediated suppression of replication stress response genes.

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Biology Commons

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