WDR5, ASH2L, and RBBP5 control the efficiency of FOS transcript processing

Area of Science:

• Molecular Biology
• Gene Regulation
• Epigenetics

Background:

• H3K4 trimethylation (H3K4me3) marks active transcription, deposited by SET-domain methyltransferases.
• The WDR5, ASH2L, and RBBP5 (WAR) subcomplex is crucial for H3K4me3 deposition.
• The ERK MAPK pathway regulates gene expression through phosphorylation events.

Purpose of the Study:

• To investigate the interplay between the WAR subcomplex and the ERK MAPK pathway.
• To explore their combined role in regulating immediate early genes (IEGs).

Main Methods:

• Depletion of WAR subcomplex components.
• Analysis of IEG transcript levels (unspliced and mature).
• Assessment of H3K4me3 levels at promoter regions.
• Focus on FOS gene regulation.

Main Results:

• WAR subcomplex depletion increased unspliced IEG transcripts without proportional changes in mature transcripts.
• This effect was independent of H3K4me3 promoter levels.
• WAR subcomplex component depletion impaired FOS transcript processing efficiency.

Conclusions:

• The WAR subcomplex plays a novel role in coordinating active transcription with efficient pre-mRNA processing.
• This suggests a link between epigenetic modification complexes and RNA processing.
• Findings reveal a new layer of gene expression regulation involving the WAR complex.