{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T09:17:34Z","timestamp":1788340654239,"version":"build-2803163510"},"reference-count":27,"publisher":"American Chemical Society (ACS)","issue":"3","license":[{"start":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T00:00:00Z","timestamp":1521072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/pubs.acs.org\/page\/policy\/authorchoice_termsofuse.html"}],"funder":[{"DOI":"10.13039\/501100001412","name":"Council of Scientific and Industrial Research","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/501100001412","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007063","name":"University of Delhi","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/501100007063","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,3,31]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>A gradual dementia, which leads to the loss of memory and intellectual abilities, is the main characteristics of Alzheimer\u2019s disease. Amyloid-\u03b2 (A\u03b2) plaques are the main components that accumulate and form clumps in the brains of people suffering from Alzheimer\u2019s disease. Apolipoprotein E (APOE), an amyloid-binding protein is considered as one of the main genetic risk factor of the late-onset Alzheimer\u2019s disease. Different isoforms of APOE gene named APOE2, APOE3, and APOE4 are known to exist, which differ from each other at certain positions involving single-nucleotide polymorphisms (SNPs). Out of these isoforms, APOE4 increases the risk of developing late-onset Alzheimer\u2019s disease, whereas APOE3 is the most common among the general population. APOE4 differs from the common APOE3 by only one nucleotide at position +2985 (T to C), which results in immense alteration in the structure and function of the APOE gene. A combination of gel electrophoresis (polyacrylamide gel electrophoresis, PAGE), circular dichroism (CD), CD melting, thermal difference spectra and UV-thermal denaturation (TM) techniques was used to investigate the structural polymorphism associated with T \u2192 C single-nucleotide polymorphism (SNP) at the GC-rich sequence (d-TGGAGGACGTGTGCGGCCGCCT; APOE22T). Herein, we report that APOE22T DNA sequence switches between hairpin to antiparallel quadruplex from low to high oligomer concentration. On the contrary, its C-counterpart (APOE22C) forms hairpin as well as intermolecular antiparallel duplex structure. This structural change may possibly contribute to the protein recognition pattern, which, in turn, might control the APOE gene expression.<\/jats:p>","DOI":"10.1021\/acsomega.7b01654","type":"journal-article","created":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T11:05:55Z","timestamp":1521111955000},"page":"3173-3182","source":"Crossref","is-referenced-by-count":12,"title":["Structural Switch from Hairpin to Duplex\/Antiparallel\nG-Quadruplex at Single-Nucleotide Polymorphism (SNP) Site of\nHuman Apolipoprotein E (\n                    <i>APOE<\/i>\n                    ) Gene Coding Region"],"prefix":"10.1021","volume":"3","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0238-1217","authenticated-orcid":true,"given":"Swati","family":"Chaudhary","sequence":"first","affiliation":[{"name":"University of Delhi , , ,","place":["Delhi, India, 110007"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mahima","family":"Kaushik","sequence":"additional","affiliation":[{"name":"University of Delhi , , ,","place":["Delhi, India, 110007"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saami","family":"Ahmed","sequence":"additional","affiliation":[{"name":"University of Delhi , , ,","place":["Delhi, India, 110007"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ritushree","family":"Kukreti","sequence":"additional","affiliation":[{"name":"CSIR-Institute of genomics and Integrative Biology , ,","place":["Delhi, India, 110007"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shrikant","family":"Kukreti","sequence":"additional","affiliation":[{"name":"University of Delhi , , ,","place":["Delhi, India, 110007"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2018,3,15]]},"reference":[{"key":"2026090204390272500_cit1","doi-asserted-by":"publisher","first-page":"106","DOI":"10.1038\/nrneurol.2012.263","article-title":"Apolipoprotein E and\nAlzheimer disease: risk, mechanisms and therapy","volume":"9","author":"Liu","year":"2013","journal-title":"Nat. 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