PexRAP Inhibits PRDM16-Mediated Thermogenic Gene Expression

Area of Science:

• Metabolism
• Cell Biology
• Endocrinology

Background:

• The nuclear receptor PPARγ's role in regulating brown and white adipose tissue development and the browning of white fat is not fully understood.
• Previous research indicated PexRAP, a peroxisomal enzyme, influences PPARγ signaling and white adipogenesis.

Purpose of the Study:

• To investigate the role of PexRAP in regulating adipose tissue types and browning.
• To elucidate the molecular mechanisms by which PexRAP affects adipocyte function and energy expenditure.

Main Methods:

• Investigated PexRAP's function in brown adipocyte gene expression and adipocyte browning.
• Identified PexRAP-interacting proteins using proteomic approaches.
• Assessed the impact of PexRAP inactivation on energy expenditure and adiposity.
• Examined the interaction of PexRAP with importin-β1, PPARγ, and PRDM16.

Main Results:

• PexRAP was identified as an inhibitor of brown adipocyte gene expression.
• PexRAP inactivation led to increased adipocyte browning, enhanced energy expenditure, and reduced adiposity.
• PexRAP interacts with importin-β1, affecting nuclear phospholipid levels.
• PexRAP disrupts the PRDM16-PPARγ complex, inhibiting adipocyte browning.

Conclusions:

• PexRAP is a key regulator of adipose tissue remodeling.
• PexRAP's function extends beyond lipid synthesis, involving nuclear transport and transcriptional regulation.
• Targeting PexRAP may offer therapeutic strategies for metabolic disorders related to adipose tissue dysfunction.