Disome-seq Services: Uncovering Ribosome Collisions and Translational Stalling

Translation isn't always a smooth highway. Detect the "traffic jams" that dictate protein fate.

High mRNA expression does not guarantee functional protein. When ribosomes stall due to cellular stress, drug treatment, or sequence anomalies, they collide—triggering quality control pathways that can degrade your therapeutic protein or alter cellular phenotypes.

CD Genomics offers premier Disome-seq (Disome Sequencing) services. We isolate and sequence the ~60nt footprints of colliding ribosomes to reveal the hidden landscape of translational pausing, co-translational folding, and Ribosome-Associated Quality Control (RQC).

  • Pinpoint Stalling: Identify exact codon sites causing ribosome traffic jams.
  • Mechanism of Action: Elucidate how drugs or stressors impact elongation dynamics.
  • High Resolution: Single-nucleotide precision for determining pause durations.
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Disome-seq ribosome collision mapping showing disome footprints and translational stress
Overview Disome-seq vs Ribo-seq Workflow Data Specs Applications Case Study FAQ

What is Disome-seq?

Disome-seq (Disome Sequencing) is a specialized high-throughput sequencing method that specifically isolates and analyzes mRNA fragments protected by two colliding ribosomes (a "disome"). Unlike standard Ribo-seq, which maps general ribosome positions, Disome-seq allows researchers to pinpoint specific ribosome stalling sites, investigate Ribosome-Associated Quality Control (RQC), and study the kinetics of co-translational protein folding by identifying where translation slows down or halts.

The Science of the "Ribosome Crash"

In the central dogma, translation is often viewed as a linear process. However, ribosomes frequently encounter obstacles—such as rare codons, rigid mRNA secondary structures, or damaged RNA—that cause the leading ribosome to stall. The trailing ribosome then collides with it, forming a Disome.

These collisions are not merely accidents; they are critical signaling events that:

  1. Trigger RQC Pathways: Initiating the degradation of the potentially toxic nascent peptide chain.
  2. Regulate Co-translational Folding: A "pause" allows protein domains time to fold correctly before synthesis continues.
  3. mRNA Surveillance: Leading to the cleavage and decay of aberrant mRNA transcripts (No-Go Decay).

By capturing the unique ~60-65 nucleotide footprint of these colliding pairs (compared to the ~28-30nt footprint of a single ribosome), Disome-seq provides a direct readout of translational stress.

Why Measure Collisions?

Our Pharma and Academic partners utilize Disome-seq to answer questions that standard RNA-seq cannot touch.

1. Mechanism of Action (MoA) Studies

Drugs targeting the translation machinery (e.g., antibiotics, anti-cancer compounds) often induce specific ribosome stalling patterns. Disome-seq reveals exactly where and how a drug disrupts elongation, providing a distinct mechanistic signature.

2. Codon Optimization for mRNA Therapeutics

For mRNA vaccines and protein replacement therapies, "smooth" translation is critical.

  • The Problem: Poor codon usage can cause stalling, leading to premature termination or protein misfolding.
  • The Solution: Disome-seq identifies "traffic jams" in your construct, guiding the replacement of problematic codons to enhance protein yield and stability.

3. Studying Protein Misfolding Diseases

In neurodegenerative conditions (e.g., Alzheimer's, Huntington's), protein aggregation is often linked to failures in RQC. Disome-seq helps map the loss of translational fidelity that contributes to aggregate formation.

4. Co-translational Folding Analysis

Protein folding begins while the chain is still emerging from the ribosome tunnel. Disome-seq maps the "pause sites" that are evolutionarily conserved to facilitate domain folding, distinguishing them from pathological stalling.

Technology Comparison: Choosing the Right Tool

We offer a multi-tiered translatome portfolio. Use this comparison to select the resolution your project requires.

Feature Polysome Profiling Ribo-seq (Standard) Disome-seq (Advanced) RNC-seq (3rd Gen)
Core Technology Sucrose Gradient + UV RNase Digestion + NGS Disome Enrichment + NGS Full-length TGS (Nanopore)
Resolution Global / Component Level Codon (Single Ribosome) Codon (Colliding Pair) Transcript Isoform Level
Primary Output Translation Efficiency (TE) ORF Localization Pause Sites & Stress Active Isoform Identity
Fragment Size N/A (Full RNA) ~28-32 nt ~50-65 nt Full Length (>1kb)
Solves For... "Is translation active?" "Where is the ribosome?" "Where is it stuck?" "Which splice variant?"
Ideal Context General Phenotype Screen Gene Expression Control RQC & Protein Folding Complex Transcriptomes

The Disome-seq Workflow

Generating high-quality disome libraries requires precise experimental handling to prevent "run-off" or false collisions.

Step 1: Cell Lysis & Ribosome Stabilization

We use a specialized lysis buffer containing elongation inhibitors (e.g., Cycloheximide or Tigecycline) to "freeze" ribosomes in place instantly, preserving the collision state.

Note: Buffer conditions are optimized to maintain the integrity of the 80S monosome and disome structures.

Step 2: RNase Digestion

Controlled digestion with RNase I is performed to degrade exposed mRNA, leaving only the RNA protected by ribosomes.

  • Crucial QC Point: Over-digestion destroys the footprint; under-digestion leaves contaminants. We titrate RNase for every sample type.

Step 3: Sucrose Gradient Fractionation

This is the defining step for Disome-seq.

We perform ultracentrifugation to separate the lysate into fractions. Unlike Ribo-seq (which targets the Monosome peak), we specifically isolate and collect the Disome Peak (representing two ribosomes).

Step 4: Library Construction & Sequencing

  • De-phosphorylation & Linker Ligation: The ~60nt RNA fragments are prepared for NGS.
  • rRNA Depletion: Removal of ribosomal RNA contaminants.
  • Sequencing: Illumina NovaSeq PE150 mode is typically used to ensure accurate mapping of the longer disome footprint.

Disome-seq workflow illustrating disome enrichment, sequencing, and pause site analysisDisome-seq workflow for isolating and sequencing ribosome collision footprints.

Advanced Bioinformatics Pipeline

Raw data is useless without a specialized computational lens. Our proprietary pipeline is tuned to distinguish collision footprints from background noise.

1. Quality Control & Pre-processing

2. Genome Mapping

Step-by-step Disome-seq data analysis workflow: filtering ribosome collisions and calculating translation pause scores.

3. P-Site Offset & Periodicity

  • Metagene Analysis: We map the 5' ends of reads relative to the Start and Stop codons.
  • 3-nt Periodicity: Like monosomes, disomes should show a 3-nucleotide periodicity (phasing), confirming they are actively engaged in the Open Reading Frame (ORF).
  • P-Site Determination: We calculate the P-site offset for both the leading and trailing ribosome within the disome footprint.

4. Pause Score & Stall Index Calculation

This is the core deliverable.

  • Genome-wide Scan: We scan every codon in the transcriptome.
  • Metric: We calculate the Pause Score = (Disome Reads at Codon X) / (Monosome Reads at Codon X).
  • Result: A high Pause Score indicates a site where ribosomes are colliding frequently relative to normal flow.

5. Motif Discovery

  • Sequence Context: We extract sequences flanking the stall sites (e.g., -30 to +30 nt).
  • Enrichment: Tools like MEME or Homer are used to identify motifs (e.g., Poly-Proline stretches, specific rare codon clusters) that are statistically enriched in the collision dataset.

Applications: Solving High-Value Problems

For mRNA Therapeutics & Vaccines

The efficacy of an mRNA drug is defined by its translation efficiency and stability.

  • Challenge: "Silent" mutations introduced during codon optimization can sometimes create accidental stall sites or increase translation speed too much, leading to misfolding.
  • Disome-seq Solution: We screen candidate sequences to ensure a "smooth" translation profile. We calculate the Codon Stabilization Coefficient (CSC) based on disome data to select codons that promote stability without causing collisions.

For Drug Discovery (Mechanism of Action)

Many small molecules affect the ribosome.

  • Elongation Inhibitors: Drugs like Emetine or Cycloheximide capture ribosomes in different conformational states. Disome-seq reveals if a drug causes "stacking" at specific motifs.
  • Stress Response Modulators: Analyzing how a drug impacts the Unfolded Protein Response (UPR) by measuring the global increase in ribosome collisions.

For Fundamental Biology

  • Gene Regulation: Discover novel regulatory elements in 3' UTRs that induce stalling to regulate protein levels.
  • Evolutionary Biology: Compare stalling patterns across species to identify conserved "slow-down" zones essential for protein function.

Sample Requirements & Specifications

Due to the rarity of disomes (typically 5-10% of the ribosome population), higher input is required than standard Ribo-seq.

Sample Type Cell Lines, Animal Tissue, Plant Tissue Fresh samples preferred; Snap-frozen accepted.
Input Amount ≥ 2 × 10^7 cells or 200mg tissue Disomes are low-abundance; high input is critical.
RIN Value ≥ 7.0 (Recommended) High integrity RNA ensures valid collision data.
Sequencing Depth > 50 Million reads / sample Deep sequencing required to detect rare stall sites.
Bioinformatics Included Mapping, Pause Score, Motif Analysis, GO Enrichment.

Case Study: Mapping Collisions in Stress Response

Study Title: Disome-seq reveals the landscape of ribosome collisions in yeast and human cells.

Source: Zhao T, et al. Genome Biology. 2021.

The researchers aimed to understand how cellular stress (oxidative stress) impacts translational dynamics globally. They utilized Disome-seq to differentiate between normal translation and pathological stalling.

  • System: HeLa cells treated with reagents to induce amino acid starvation or oxidative stress.
  • Technique: Disome-seq libraries were constructed by isolating the disome fraction from sucrose gradients after RNase digestion.
  1. Structural Validation: The study confirmed that Disome-seq captures a precise ~62 nt footprint, corresponding to two tightly packed ribosomes.
  2. Stress Response: Under oxidative stress, there was a global accumulation of disomes, specifically at sites encoding amino acids sensitive to oxidation.

Disome-seq data from Zhao et al 2021 showing ribosome collisions accumulating at stop codons under stress. A Metagene plot showing a dramatic accumulation of disome reads (peaks) at the Stop codon and specific internal pause sites under stress conditions, compared to untreated controls.

The study demonstrated that Disome-seq is a powerful tool for monitoring translational distress, revealing that "ribosome traffic jams" are a regulated aspect of the cellular stress response.

Frequently Asked Questions (FAQ)

References:

  1. Zhao, T., et al. Disome-seq reveals the landscape of ribosome collisions in yeast and human cells. Genome Biology 22, 28 (2021).
  2. Arpat AB., et al. Transcriptome-wide sites of collided ribosomes reveal principles of translational pausingGenome Res. 2020
  3. Su, S., et al. Comparative analysis of translatomics and transcriptomics in the longissimus dorsi muscle of Luchuan and Duroc pigs. PLoS One 20, 3 (2025).
  4. Zhao, J., et al. Translatomics: The Global View of Translation. Int. J. Mol. Sci. 20, 1 (2019).


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  • For research purposes only, not intended for clinical diagnosis, treatment, or individual health assessments.
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