Project description:SRSF3 (SRp20) is an essential RNA splicing factor. By conditional knockout (KO) of Srsf3, we discovered Srsf3 at its physiological level plays a tumor-suppressive role in mouse liver carcinogenesis. Srsf3 KO in hepatocytes led to disrupt sex disparity in the development of DEN-induced liver cancer and resulted in high incidence of liver cancer in both male and female mice. In contrast, Srsf3 is oncogenic in the mouse mammary glands and Srsf3 KO significantly delayed the development of Erbb2 breast cancer. Srsf3 KO significantly increased the expression of transcription factors Sox4, E2f1, and Myc, calcium channel factor Trpv4, and zinc-binding Trim6 in liver cancer, but did not in Erbb2 breast cancer. Srsf3 KO enhanced the expression of glucose transmembrane transporter Mfsd4a and translation initiator Eif4a2 in DEN-induced liver cancer but reduced Mfsd4a and Eif4a2 expression in breast cancer. More importantly, Srsf3 KO led to reduced expression of hepatocyte ERα and transcription factor Foxa family genes essential for sexual dimorphism in liver cancer and their downstream targets leukemia inhibitory factor receptor Lifr and epidermal growth factor receptor Egfr, but increased expression of Myc. We further evidenced that SRSF3 binds to FOXA1 promoter and is responsible for FOXA1 promoter activity and FOXA1 expression in liver cancer cells. Together, our data highlights a new functional paradigm of SRSF3 at its physiological level in tissue context-dependent gene regulation and in facilitating hepatocyte ERα and FOXA1 expression for sex disparity in liver cancer development.
Project description:This dataset examines the proteome of elongated spermatids in the testes of adult Mex3d knockout mice, with age-matched wild-type littermates used as controls.
Project description:mRNA expression was compared between wild type and hepatocyte-specific caveolin-1 knockout livers in healthy and non-alcoholic fatty liver disease (NAFLD) mice mRNA expression was compared between gender
Project description:The ER-resident prote in fat-inducing transcript 2 (FIT2) catalyzes acyl-CoA cleavage in vitro, and in cells is required for endoplasmic reticulum (ER)homeostasis and normal lipid storage. The gene encoding FIT2 is essential for viability of mice and worms. Whether FIT2 acts as anacyl-CoA diphosphatase in vivo and how this activity affects liver, where the protein was discovered,is unknown. Here, we report that hepatocyte-specific Fitm2 knockout (FIT2-LKO) mice exhibited elevated acyl-CoA levels, ER stress, and signs of liver injury. FIT2-LKO mice had increased triglyceride (TG) content in liver when fed a chow diet, compared with control littermates due in part to impaired secretion of TG-rich lipoproteins and reduced capacity for fatty acid oxidation. Challenging FIT2-LKO mice with a high-fat diet to increase FIT2 acyl-CoA substrates worsened hepatic ER stress and liver injury, yet unexpectedly reversed the steatosis phenotype, similar to what is observed in FIT2-deficient cells loaded with fatty acids. Our findings show that FIT2 acts as anacyl-CoA diphosphatase in vivo and is crucial for normal hepatocyte function and ER homeostasis in murine liver
