The long noncoding RNA CHROME regulates cholesterol homeostasis in primate.

Area of Science:

• Genomics
• Molecular Biology
• Cardiovascular Research

Background:

• The human genome contains numerous long non-coding RNAs (lncRNAs), many of which remain uncharacterized.
• Dysregulation of cholesterol homeostasis is a hallmark of cardiovascular diseases like coronary artery disease.

Purpose of the Study:

• To identify and characterize novel lncRNAs involved in cholesterol regulation.
• To investigate the role of a primate-specific lncRNA, CHROME, in cholesterol homeostasis and its potential link to coronary artery disease.

Main Methods:

• Identification of a primate-specific lncRNA (CHROME) in plasma and atherosclerotic plaques.
• Analysis of CHROME expression regulation by dietary and cellular cholesterol via liver X receptors.
• Gain- and loss-of-function studies in human hepatocytes and macrophages to assess CHROME's impact on cholesterol efflux and HDL biogenesis.
• MicroRNA profiling (miR-27b, miR-33a, miR-33b, miR-128) and target gene analysis, including ABCA1.

Main Results:

• CHROME expression is elevated in individuals with coronary artery disease and is influenced by cholesterol levels.
• CHROME promotes cholesterol efflux and HDL biogenesis by inhibiting specific microRNAs (miR-27b, miR-33a, miR-33b, miR-128).
• CHROME knockdown leads to reduced expression of ABCA1, a key regulator of cholesterol efflux and HDL formation.

Conclusions:

• CHROME is a novel primate-specific lncRNA that critically regulates cholesterol homeostasis.
• CHROME acts as a central component in the non-coding RNA regulatory network controlling cholesterol metabolism.
• CHROME represents a potential therapeutic target for managing cholesterol levels and treating cardiovascular diseases.