CUTANA™ Hia5 for Fiber-seq

CUTANA™ Hia5 is the key enzyme for Fiber-seq [1], a multiomic long-read sequencing (LRS) assay that simultaneously profiles chromatin accessibility, DNA methylation, and genetic variation at single-molecule resolution. By layering chromatin accessibility on top of standard LRS workflows, Fiber-seq uniquely links epigenetic information (DNA methylation) and complex genetic architecture (e.g., structural variants and haplotype phasing) to chromatin states within the same molecules of DNA. Hia5 is a DNA adenine methyltransferase (MTase) that uses S-adenosylmethionine (SAM) to catalyze methylation at the N6 position of adenine, producing N6-methyladenine (6mA). Fiber-seq leverages the nonspecific activity of Hia5 to methylate adenines within accessible chromatin regions in situ. This records chromatin accessibility information onto native DNA while preserving endogenous methylation (5mC). Hia5-modified DNA is fully compatible with LRS on both Pacific Biosciences® (PacBio® HiFi Sequencing) and Oxford Nanopore Technologies® (ONT® Nanopore Sequencing) platforms. Key Advantages Multiomic insights in one assay - Fiber-seq simultaneously profiles chromatin accessibility, DNA methylation, and genetic variants, consolidating what typically requires three or more separate assays into one long-read sequencing assay. Highest activity 6mA-MTase - Faster labeling via Hia5 enables higher resolution of accessible DNA, with demonstrated utility in protein footprinting applications to resolve transcription factor binding and nucleosome positioning [2-4]. Access complex genomic regions - Profile chromatin accessibility in repetitive and structurally complex regions such as transposable elements, centromeres, telomeres, segmental duplications, and chromosomal rearrangements. Easy workflow integration - Fiber-seq can be performed in <2 hours directly upstream of routine long-read sequencing library preparation. Resolve chromatin state heterogeneity - PCR-free approach leverages long-read sequencing to directly profile individual DNA molecules, uncovering chromatin structure heterogeneity in cell populations often missed by short-read techniques.