Genome-wide translational profiling by ribosome footprinting

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Accurate measurement of gene expression at the translational level is crucial for understanding cellular processes.
• Existing methods lack the resolution to precisely map ribosome positions on mRNA.
• Quantitative analysis of translation provides insights into translational regulation.

Purpose of the Study:

• To present a detailed protocol for ribosome profiling, a novel technique for comprehensive and quantitative measurement of translation.
• To enable precise determination of ribosome positions on mRNA templates in yeast.
• To facilitate reproducible measurements of translational control and gene expression.

Main Methods:

• Ribosome profiling involves determining ribosome positions from their nuclease footprint on mRNA.
• Footprints are converted into a DNA library for deep sequencing using Illumina Genome Analyzer.
• Optimization of nuclease digestion conditions yields uniform ~28 nucleotide mRNA fragments.

Main Results:

• Ribosome profiling enables highly reproducible measurements of translational control.
• The technique revealed the presence of ribosomes on upstream open reading frames.
• Higher ribosome density was observed near the beginning of protein-coding genes.

Conclusions:

• Ribosome profiling is a powerful tool for quantitative analysis of translation.
• This method provides unprecedented resolution for studying ribosome dynamics and translational regulation.
• The protocol facilitates deep sequencing data analysis for precise gene expression quantification.