Ribosome slowdown triggers codon-mediated mRNA decay independently of ribosome quality control

Area of Science:

• Molecular Biology
• Genetics
• Developmental Biology

Background:

• mRNA stability is a key regulator of gene expression.
• Recent research indicates codon composition within the open reading frame influences mRNA stability across organisms.
• This effect is linked to the kinetics of codon decoding by the ribosome.

Purpose of the Study:

• To experimentally investigate codon-mediated mRNA decay and ribosome stall-dependent mRNA decay.
• To clarify the mechanisms underlying codon effects on mRNA stability in zebrafish embryos.
• To differentiate codon-mediated decay from pathways involving ribosome stalling.

Main Methods:

• Utilized reporter-based analyses in zebrafish embryos.
• Performed genome-wide correlation approaches.
• Investigated the role of ribosome stalling and the Znf598 factor.

Main Results:

• Codon effects on mRNA stability are mediated by the decoding process.
• This process is independent of the ribosome quality control factor Znf598.
• Stalling-dependent mRNA decay pathways do not account for codon-mediated effects.

Conclusions:

• Codon-mediated mRNA decay in zebrafish embryos is triggered by transiently slowed ribosomes.
• These slowed ribosomes remain engaged in a productive translation cycle.
• The genetic code's kinetic properties directly impact mRNA stability and gene expression regulation.