Srf conditional knockout in the mouse liver

Serum response factor (SRF) is a transcription factor that binds to the serum response element (SRE) of genes that are expressed in response to mitogens. SRF plays essential roles in muscle and nervous system development; however, little is known about the role of SRF during liver growth and function. To examine the function of SRF in the liver, we generated mice in which the Srf gene was specifically disrupted in hepatocytes. The survival of mice lacking hepatic SRF activity was lower than that of control mice; moreover, surviving mutant mice were smaller and had lower blood glucose and triglyceride levels compared with control mice. Srf-deficient livers were also smaller than control livers, hepatocyte morphology was abnormal, and liver-cell proliferation and viability was compromised. Gene array and quantitative RT-PCR analysis of SRF depleted livers revealed a reduction in mRNAs encoding components of the growth hormone/IGF1 pathway, cyclins, several metabolic regulators, and cytochrome p450 enzymes. Conclusion: SRF is essential for hepatocyte proliferation and survival, liver function, and control of postnatal body growth by regulating hepatocyte gene expression.

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