A brand new molecular recording technique is giving researchers a technique to seize DNA–protein interactions in single cells, together with the weak and transient contacts that form gene regulation however typically slip previous current assays. The strategy, referred to as D&D‑seq (docking and deamination adopted by sequencing), layers a base‑modifying enzyme onto an antibody‑binding nanobody, turning fleeting interactions into sturdy sequence marks.
The paper is titled “Single-cell mapping of regulatory DNA-protein interactions,” and was revealed just lately in Cell.
“D&D-seq {couples} an antibody-binding nanobody to a cytosine base editor, a mix that allows detection of weak or transient issue binding by way of focused cytosine-to-uracil [C→U] modifying at protein-bound genomic websites,” the authors wrote. These edits grow to be a molecular breadcrumb path, revealing the place regulatory proteins have interacted with the genome.
This strategy immediately addresses a protracted‑standing hole within the area. Conventional strategies for mapping transcription issue binding, corresponding to ChIP‑seq or CUT&RUN, “can’t be simply integrated into high-throughput single-cell workflows, limiting functions to bulk evaluation or to single-cell profiling of solely the strongest interacting chromatin elements. Single-cell profiling of TF binding in main samples has been primarily restricted to inferential approaches based mostly on expression ranges of downstream TF goal genes or by way of motif evaluation of assay for transposase-accessible chromatin utilizing sequencing (ATAC-seq) peaks, however identification of particular TF-binding websites requires extra direct strategies,” in response to the authors.
The workforce demonstrated that D&D‑seq can map binding websites for transcription elements and different regulatory proteins, like chromatin reworking proteins, throughout a number of cell varieties and situations. One utility concerned profiling CTCF binding in main T cells carrying an IDH2 mutation generally present in leukemia. As a result of D&D‑seq operates at single‑cell decision, it exposes heterogeneity in regulatory wiring that’s typically masked in inhabitants‑stage assays.
Crucially, the tactic is platform‑agnostic. The authors confirmed that D&D‑seq may be built-in into commonplace single‑cell multiomics workflows, together with ATAC‑seq, scATAC‑seq, and entire‑genome sequencing. That compatibility permits researchers to pair DNA–protein interplay maps with chromatin accessibility, gene expression, and genomic variation—all inside the similar cell.
As transcription elements and different regulatory proteins more and more emerge as therapeutic targets, instruments that reveal how these elements behave in affected person‑derived cells will likely be important. D&D‑seq presents a technique to monitor how mutations, medicine, or engineered perturbations reshape regulatory landscapes at single‑cell decision.
“We’re getting into an period of drugs during which transcription elements and different gene-activity regulators will more and more be therapeutic targets,” stated Dan Landau, MD, PhD, the Bibliowicz Household professor of drugs and a member of the Sandra and Edward Meyer Most cancers Middle and the Englander Institute for Precision Drugs at Weill Cornell, who can be an oncologist at NewYork-Presbyterian/Weill Cornell Medical Middle. “This sort of know-how ought to have an essential position in creating and evaluating such therapies.”
Though the tactic continues to be evolving, its conceptual class and technical flexibility have already sparked broad curiosity. By turning DNA right into a recording floor for protein exercise, D&D‑seq opens a brand new window into the “regulome”—one which captures the refined, transient interactions that drive mobile id and illness.
