A model for farnesoid feedback control in the mevalonate pathway

Area of Science:

• Biochemistry
• Molecular Biology
• Metabolic Regulation

Background:

• Mevalonate pathway is crucial for isoprenoid synthesis, including cholesterol.
• Identifying regulatory molecules in isoprenoid biosynthesis remains a challenge.
• Farnesyl pyrophosphate (FPP) is a central intermediate in this pathway.

Purpose of the Study:

• To investigate the role of nuclear receptors in regulating isoprenoid biosynthesis.
• To identify signaling molecules involved in the feedback control of cholesterol synthesis.
• To explore the function of FXR in the mevalonate pathway.

Main Methods:

• Characterization of nuclear receptor FXR.
• Analysis of FXR activation by farnesyl pyrophosphate metabolites.
• Examination of FXR expression in isoprenoidogenic tissues.

Main Results:

• FXR was identified as a nuclear receptor activated by farnesyl pyrophosphate metabolites (farnesol, farnesal, farnesoic acid, methyl farnesoate).
• FXR expression was detected in tissues involved in isoprenoid production.
• These findings support a role for intracellular farnesoids as signaling molecules.

Conclusions:

• FXR activation by farnesoid metabolites suggests a novel feedback mechanism.
• Intracellular farnesoids may act as signals for transcriptional regulation of cholesterol biosynthesis.
• FXR represents a potential target for modulating isoprenoid metabolic pathways.