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===Resolution===
In budding yeast ''[[Saccharomyces cerevisiae]]'', Holliday junctions can be resolved by four different pathways that account for essentially all Holliday junction resolution [[in vivo]].<ref name=Zakh>{{cite journal | last1 = Zakharyevich | first1 = K | last2 = Tang | first2 = S | last3 = Ma | first3 = Y | last4 = Hunter | first4 = N | date = Apr 2012 | title = Delineation of joint molecule resolution pathways in meiosis identifies a crossover-specific resolvase | url = | journal = Cell. | volume = 149 | issue = 2| pages = 334–47 | doi = 10.1016/j.cell.2012.03.023 | pmid = 22500800 | pmc=3377385}}</ref> The pathway that produces the majority of [[Chromosomal crossover|crossovers]] in ''S. cerevisiae'' budding yeast, and possibly in mammals, involves proteins [[Exonuclease 1|EXO1]], [[MLH1]]-[[MLH3]] heterodimer (called MutL gamma) and [[Sgs1|SGS1]] (ortholog of [[Bloom syndrome protein|Bloom syndrome helicase]]).<ref name=Zakh /> The MLH1-MLH3 heterodimer binds preferentially to Holliday junctions.<ref name=Ranjha>Ranjha L, Anand R, Cejka P. 2014. The Saccharomyces cerevisiae Mlh1-Mlh3 heterodimer is an endonuclease that preferentially binds to Holliday junctions. J Biol Chem. 2014 Feb 28;289(9):5674-86. doi: 10.1074/jbc.M113.533810. PMID 24443562</ref> It is an endonuclease that makes single-strand breaks in supercoiled double-stranded DNA.<ref name=Ranjha /><ref name="pmid24403070">{{vcite2 journal |vauthors=Rogacheva MV, Manhart CM, Chen C, Guarne A, Surtees J, Alani E |title=Mlh1-Mlh3, a meiotic crossover and DNA mismatch repair factor, is a Msh2-Msh3-stimulated endonuclease |journal=J. Biol. Chem. |volume=289 |issue=9 |pages=5664–73 |year=2014 |pmid=24403070 |pmc=3937641 |doi=10.1074/jbc.M113.534644 |url=}}</ref> The MLH1-MLH3 heterodimer promotes the formation of [[Chromosomal crossover|crossover recombinants]].<ref name=Brown>{{vcite2 journal |vauthors=Sonntag Brown M, Lim E, Chen C, Nishant KT, Alani E |title=Genetic analysis of mlh3 mutations reveals interactions between crossover promoting factors during meiosis in baker's yeast |journal=G3:
Double mutants deleted for both MLH3 (major pathway) and MMS4 (minor pathway) showed dramatically reduced crossing over compared to wild-type (6- to 17-fold); however spore viability was reasonably high (62%) and chromosomal disjunction appeared mostly functional.<ref name=Brown />
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== Use in DNA nanotechnology ==
[[File:Mao-DX-schematic-2.svg|thumb| This double-crossover (DX) [[supramolecular complex]] contains two Holliday junctions between the two [[Double helix|double-helical]] domains, on the top and the bottom in this image. This tile is capable of forming two-dimensional arrays.<ref name="Mao04">{{cite journal | last=Mao | first=Chengde | date=December 2004 | title=The emergence of complexity: lessons from DNA | journal=PLoS Biology | volume=2 | issue=12 | pages=2036–2038 | pmid=15597116 | pmc=535573 | doi=10.1371/journal.pbio.0020431}}</ref>]]
{{Main article | DNA nanotechnology}}
DNA nanotechnology is the design and manufacture of artificial nucleic acid structures as engineering materials for [[nanotechnology]] rather than as the carriers of genetic information in living cells. The field uses branched DNA structures as fundamental components to create more complex, rationally designed structures. Holliday junctions are thus components of many such DNA structures. As isolated Holliday junction complexes are too flexible to assemble into large ordered arrays, [[structural motif]]s with multiple Holliday junctions are used to create rigid "[[tessellation|tiles]]" that can then assemble into larger "arrays".<ref name="Seeman-sciam">{{cite journal | last=Seeman | first=Nadrian C. | title=Nanotechnology and the double helix | journal=Scientific American | date=June 2004 | pages=64–75 | pmid=15195395 | url=http://www.scientificamerican.com/article.cfm?id=nanotechnology-and-the-do | volume=290 | issue=6 | doi=10.1038/scientificamerican0604-64}}</ref><ref name="Seeman2010">{{Cite journal | last1 = Seeman | first1 = Nadrian C. | doi = 10.1146/annurev-biochem-060308-102244 | title = Nanomaterials based on DNA | journal = Annual Review of Biochemistry | volume = 79 | pages = 65–87 | year = 2010 | pmid = 20222824| pmc = 3454582}}</ref>
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