Molecular Biology and Evolution<\/a>, focused on a group of genes called SERPINs, which encode a protein that blocks a common ingredient in snake venom. Previous research demonstrated that SERPINA1 inhibits European rattlesnake venom, but much less is known about a related gene called SERPINA3.<\/p>\n\u201cWe wanted to see if we could determine a genetic basis underlying this venom resistance,\u201d says Matthew Holding, an evolutionary biologist in the lab of David Ginsburg at the University of Michigan Life Sciences Institute.<\/p>\n
\u201cWe noticed that, whereas humans have only one SERPINA3 gene, these rats have 12 copies. They each encode a slightly different protein, and we have no idea what any of them do.\u201d<\/p>\n
This research was supported by the National Institutes of Health and the University of Michigan\u2019s Honors Summer Fellowship.<\/p>\n
The dozen SERPINA3 genes in woodrats arose through a process called tandem duplication, whereby an extra copy of one gene is inserted into the genome during development. Because the original gene remains intact, performing its original functions, the new copy may evolve to encode a different protein with another function.<\/p>\n
Tandem duplications are frequently found in snake venom. As snakes\u2019 prey become resistant to the venom, new proteins evolve to make the venom toxic in other ways. The research team wondered if genetic changes in snake venom could be driving SERPINA3 to duplicate and diversify in response.<\/p>\n
Meilyn Ward, a former undergraduate student in the Ginsburg lab who co-led the study with Holding, tested the proteins made by each of the 12 woodrat SERPINA3 genes against venom samples gathered from the rattlesnakes that hunt these rodents. They found that many of the SERPINA3 proteins bound directly to components of the venom that make it toxic, blocking their ability to cause damage.<\/p>\n
The research team also observed substantial variation in the different proteins\u2019 activities. Some of the proteins did not show any interaction with the venom, indicating that they have an entirely different role in the mammals\u2019 survival, whereas another protein simultaneously inhibited two different components that form the basis of the venom\u2019s toxicity.<\/p>\n
\u201cOur findings brought SERPINA3 proteins into the conversation about venom resistance,\u201d says Ward, who is now a medical student at Duke University. \u201cPrevious work in this area had focused mainly on SERPINA1, and we now know that these duplicate SERPINA3 genes are an important factor in the coevolution between woodrats and their predators.<\/p>\n
Holding says this gives us an idea of how gene duplication can play a role in the evolution of venom resistance, as one of potentially many factors.<\/p>\n
\u201cAnd it uncovers one more tool in the rodents\u2019 toolbox and that can be studied across other animals as part of this larger question of how to survive venomous snakebites,\u201d he says.<\/p>\n
In addition to Holding and Ward, study authors were Laura Haynes and David Ginsburg of the University of Michigan, Mark Margres of the University of South Florida, and Marjorie Matocq of the University of Nevada Reno.<\/p>\n
Source: University of Michigan<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Share this Article You are free to share this article under the Attribution 4.0 International license. A genetic…\n","protected":false},"author":2,"featured_media":202395,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[61,60,11166,82,5199],"class_list":{"0":"post-202394","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-ie","9":"tag-ireland","10":"tag-rodents","11":"tag-science","12":"tag-snakes"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/202394","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=202394"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/202394\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/202395"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=202394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=202394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=202394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}