Understanding Codon Usage Bias Disruption

Codon usage bias refers to the non-random selection of codons when coding for amino acids. In highly expressed genes, this bias typically aligns with the abundance of corresponding tRNAs, enabling efficient protein synthesis.

Effects on Translation Rate

Disrupting the codon usage bias in highly expressed genes can slow down the translation rate. The presence of rare codons necessitates waiting periods for less abundant tRNAs, impeding the ribosome's progression along the mRNA and thus reducing the speed of protein synthesis.

Effects on Translation Accuracy

Altering the codon usage bias can also compromise translation accuracy. Ribosomal pauses induced by suboptimal codons may increase the likelihood of errors, such as the incorporation of incorrect amino acids by near-cognate tRNAs. Correct codon usage ensures the right charged tRNA is readily available, enhancing fidelity.

Transcription Processes

The primary impact of codon usage bias disruption occurs during translation. While transcription and translation are coupled in some organisms, significant effects on transcription rate or transcription accuracy are less direct compared to the immediate consequences on translation.

Affected Genetic Processes

Based on the direct effects:

• Translation rate
• Translation accuracy

These are the genetic processes most likely affected by the disruption of codon usage bias in highly expressed genes.