{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T03:29:58Z","timestamp":1791343798344,"version":"4.3.1"},"reference-count":49,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2014,11,6]],"date-time":"2014-11-06T00:00:00Z","timestamp":1415232000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Exposure to the ultraviolet component of sunlight causes DNA damage, which subsequently leads to mutations, cellular transformation, and cell death. DNA photoproducts with (6-4) pyrimidine-pyrimidone adducts are more mutagenic than cyclobutane pyrimidine dimers. These lesions must be repaired because of the high mutagenic potential of (6-4) photoproducts. We here reviewed the structures of (6-4) photoproducts, particularly the detailed structures of the (6-4) lesion and (6-4) lesion-containing double-stranded DNA.  We also focused on interactions with their binding proteins such as antibody Fabs,  (6-4) photolyase, and nucleotide excision repair protein. The (6-4) photoproducts that bound to these proteins had common structural features: The 5'-side thymine and 3'-side pyrimidone bases of the T(6-4)T segment were in half-chair and planar conformations, respectively, and both bases were positioned nearly perpendicularly to each other. Interactions with binding proteins showed that the DNA helices flanking the T(6-4)T segment were largely kinked, and the flipped-out T(6-4)T segment was recognized by these proteins. These proteins had distinctive binding-site structures that were appropriate for their functions.<\/jats:p>","DOI":"10.3390\/ijms151120321","type":"journal-article","created":{"date-parts":[[2014,11,7]],"date-time":"2014-11-07T02:03:59Z","timestamp":1415325839000},"page":"20321-20338","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":57,"title":["Structural Biology of DNA (6-4) Photoproducts Formed  by Ultraviolet Radiation and Interactions with Their  Binding Proteins"],"prefix":"10.3390","volume":"15","author":[{"given":"Hideshi","family":"Yokoyama","sequence":"first","affiliation":[{"name":"School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku,  Shizuoka 422-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryuta","family":"Mizutani","sequence":"additional","affiliation":[{"name":"Department of Applied Biochemistry, School of Engineering, Tokai University,  Kanagawa 259-1292, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,11,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1038\/362709a0","article-title":"Instability and decay of the primary structure of DNA","volume":"362","author":"Lindahl","year":"1993","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"805","DOI":"10.1111\/j.1751-1097.1989.tb05578.x","article-title":"The biology of the (6-4) photoproduct","volume":"49","author":"Mitchell","year":"1989","journal-title":"Photochem. 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