{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T22:52:17Z","timestamp":1781823137312,"version":"3.54.5"},"reference-count":29,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Epigenet. Epigenom."],"abstract":"<jats:p>\n                    Cellular development and differentiation are critically regulated by the spatiotemporal expression of genes within the genome, which are packaged into a highly organized chromatin structure. Genes in the human genome are often regulated by long-distance promoter\u2013enhancer interactions. To better understand gene expression regulation, it is essential to identify specific interactions between distal\n                    <jats:italic>cis<\/jats:italic>\n                    -regulatory elements and their target promoters. To this end, we developed Hi-TrAC, a technique that generates high-resolution interaction maps among accessible chromatin regions without relying on\n                    <jats:italic>in vitro<\/jats:italic>\n                    proximity ligation, while maintaining low sequencing cost. In addition, Hi-TrAC provides a genome-wide landscape of chromatin accessibility. In this article, we present a robust detailed protocol for performing Hi-TrAC assay.\n                  <\/jats:p>","DOI":"10.3389\/freae.2026.1858923","type":"journal-article","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T22:10:15Z","timestamp":1781820615000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Elucidation of chromatin loops among regulatory regions using Hi-TrAC"],"prefix":"10.3389","volume":"4","author":[{"given":"Yaqiang","family":"Cao","sequence":"first","affiliation":[{"name":"Laboratory of Epigenome Biology, Systems Biology Center, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health","place":["Bethesda, MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qingsong","family":"Tang","sequence":"additional","affiliation":[{"name":"Laboratory of Epigenome Biology, Systems Biology Center, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health","place":["Bethesda, MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keji","family":"Zhao","sequence":"additional","affiliation":[{"name":"Laboratory of Epigenome Biology, Systems Biology Center, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health","place":["Bethesda, MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1758","DOI":"10.1126\/science.1200700","article-title":"Revealing the dark matter of the genome","volume":"330","author":"Blaxter","year":"2010","journal-title":"Science"},{"key":"B2","doi-asserted-by":"publisher","first-page":"1213","DOI":"10.1038\/nmeth.2688","article-title":"Transposition of native chromatin for fast and sensitive epigenomic profiling of open chromatin, DNA-Binding proteins and nucleosome position","volume":"10","author":"Buenrostro","year":"2013","journal-title":"Nat. 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