Editing Reverse transcriptase (section)

== In cellular life ==

Self-replicating stretches of [[eukaryotic]] genomes known as [[retrotransposon]]s utilize reverse transcriptase to move from one position in the genome to another via an RNA intermediate. They are found abundantly in the genomes of plants and animals. [[Telomerase]] is another reverse transcriptase found in many eukaryotes, including humans, which carries its own [[RNA]] template; this RNA is used as a template for [[DNA replication]].<ref name="isbn0-7167-4366-3">{{cite book | vauthors = Krieger M, Scott MP, Matsudaira PT, Lodish HF, Darnell JE, Zipursky L, Kaiser C, Berk A | title = Molecular cell biology | publisher = W.H. Freeman and CO | location = New York | year = 2004 | isbn = 978-0-7167-4366-8 | url-access = registration | url = https://archive.org/details/molecularcellbio00harv }}</ref>

Initial reports of reverse transcriptase in prokaryotes came as far back as 1971 in France ([[Mirko Beljanski|Beljanski]] et al., 1971a, 1972) and a few years later in the USSR (Romashchenko 1977<ref>{{cite journal | vauthors = Romashchenko AG, etal |title=Otdelenie ot preparatov DNK-polimeraz I RNK-zavisimoy DNK-polimeraz; oshistka i svoystva fermenta |journal=[[Proceedings of the USSR Academy of Sciences]] |date=1977 |volume=233 |pages=734–737}}</ref>).  These have since been broadly described as part of bacterial [[Retron]]s, distinct sequences that code for reverse transcriptase, and are used in the synthesis of [[multicopy single-stranded DNA|msDNA]]. In order to initiate synthesis of DNA, a primer is needed. In bacteria, the primer is synthesized during replication.<ref name="pmid4333538">{{cite journal | vauthors = Hurwitz J, Leis JP | title = RNA-dependent DNA polymerase activity of RNA tumor viruses. I. Directing influence of DNA in the reaction | journal = Journal of Virology | volume = 9 | issue = 1 | pages = 116–29 | date = January 1972 | pmid = 4333538 | pmc = 356270 | doi =  10.1128/JVI.9.1.116-129.1972}}</ref>

Valerian Dolja of Oregon State argues that viruses, due to their diversity, have played an evolutionary role in the development of cellular life, with reverse transcriptase playing a central role.<ref>{{cite news | last1 = Arnold | first1 = Carrie | name-list-style = vanc | title = Could Giant Viruses Be the Origin of Life on Earth? | url = http://news.nationalgeographic.com/news/2014/07/140716-giant-viruses-science-life-evolution-origins/ | archive-url = https://web.archive.org/web/20140718130943/http://news.nationalgeographic.com/news/2014/07/140716-giant-viruses-science-life-evolution-origins/ | url-status = dead | archive-date = July 18, 2014 | access-date = 29 May 2016 | work = National Geographic |date=17 July 2014}}</ref>