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Updated: Aug 14, 2026

An Adipocyte Cell Culture Model to Study the Impact of Protein and Micro-RNA Modulation on Adipocyte Function
09:20

An Adipocyte Cell Culture Model to Study the Impact of Protein and Micro-RNA Modulation on Adipocyte Function

Published on: May 4, 2021

Protein inhibitor of activated STAT3 inhibits adipogenic gene expression

Jianbei Deng1, Kunjie Hua, Erica J Caveney

  • 1Department of Nutrition, CB# 7461, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.

Biochemical and Biophysical Research Communications
|December 7, 2005
PubMed

Insights

Protein inhibitor of activated STAT3 (PIAS3) inhibits adipogenesis by affecting insulin signaling. Increased PIAS3 in adipose tissue may contribute to obesity-related metabolic issues.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Background:

  • Protein inhibitor of activated STAT3 (PIAS3) is expressed in white adipose tissue.
  • The role of PIAS3 in adipogenesis (fat cell formation) is currently unknown.
  • PIAS3 is a repressor of signal transducer and activator of transcription 3 (STAT3).

Purpose of the Study:

  • To investigate the role of PIAS3 in adipogenesis.
  • To determine PIAS3's cellular localization and expression patterns during fat cell differentiation.
  • To elucidate PIAS3's impact on key adipogenic gene expression and signaling pathways.

Main Methods:

  • Studied PIAS3 expression and localization in 3T3-L1 cells during adipogenesis.
  • Analyzed PIAS3 expression in white adipose tissue of ob/ob mice versus lean mice.
  • Utilized PIAS3 overexpression in preadipocytes to assess effects on adipogenic gene expression and promoter activity.

Main Results:

  • PIAS3 translocated from the nucleus to the cytoplasm during 3T3-L1 cell differentiation.
  • PIAS3 expression was elevated in the white adipose tissue of obese mice.
  • Overexpression of PIAS3 inhibited key adipogenic transcription factors (C/EBPalpha, PPARgamma) and downstream genes (aP2, adiponectin).
  • PIAS3 specifically inhibited insulin-mediated C/EBPalpha promoter activation.

Conclusions:

  • PIAS3 appears to inhibit adipogenesis by modulating insulin-activated transcription.
  • Elevated PIAS3 in adipose tissue may contribute to metabolic disturbances associated with obesity.

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