{"id":74,"date":"2006-07-14T11:27:00","date_gmt":"2006-07-14T11:27:00","guid":{"rendered":"http:\/\/scientopia.org\/blogs\/goodmath\/2006\/07\/14\/using-good-math-to-study-evolution-using-fitness-landscapes\/"},"modified":"2006-07-14T11:27:00","modified_gmt":"2006-07-14T11:27:00","slug":"using-good-math-to-study-evolution-using-fitness-landscapes","status":"publish","type":"post","link":"http:\/\/www.goodmath.org\/blog\/2006\/07\/14\/using-good-math-to-study-evolution-using-fitness-landscapes\/","title":{"rendered":"Using Good Math to Study Evolution Using Fitness Landscapes"},"content":{"rendered":"<p>Via [Migrations][migrations], I&#8217;ve found out about a really beautiful computational biology paper that very elegantly demonstrates how, contrary to the [assertions of bozos like Dembski][dembski-nfl], an evolutionary process can adapt to a fitness landscape. The paper was published in the PLOS journal &#8220;Computational Biology&#8221;, and it titled [&#8220;Evolutionary Potential of a Duplicated Repressor-Operator Pair: Simulating Pathways Using Mutation Data&#8221;][plos].<br \/>\nHere&#8217;s their synopsis of the paper:<br \/>\n&gt;The evolution of a new trait critically depends on the existence of a path of<br \/>\n&gt;viable intermediates. Generally speaking, fitness decreasing steps in this path<br \/>\n&gt;hamper evolution, whereas fitness increasing steps accelerate it.<br \/>\n&gt;Unfortunately, intermediates are hard to catch in action since they occur only<br \/>\n&gt;transiently, which is why they have largely been neglected in evolutionary<br \/>\n&gt;studies.<br \/>\n&gt;<br \/>\n&gt;The novelty of this study is that intermediate phenotypes can be predicted<br \/>\n&gt;using published measurements of Escherichia coli mutants. Using this approach,<br \/>\n&gt;the evolution of a small genetic network is simulated by computer. Following<br \/>\n&gt;the duplication of one of its components, a new protein-DNA interaction<br \/>\n&gt;develops via the accumulation of point mutations and selection. The resulting<br \/>\n&gt;paths reveal a high potential to obtain a new regulatory interaction, in which<br \/>\n&gt;neutral drift plays an almost negligible role. This study provides a<br \/>\n&gt;mechanistic rationale for why such rapid divergence can occur and under which<br \/>\n&gt;minimal selective conditions. In addition it yields a quantitative prediction<br \/>\n&gt;for the minimum number of essential mutations.<br \/>\nAnd one more snippet, just to show where they&#8217;re going, and to try to encourage you to make the effort to get through the paper. This isn&#8217;t an easy read, but it&#8217;s well worth the effort.<br \/>\n&gt;Here we reason that many characteristics of the adaptation of real protein-DNA<br \/>\n&gt;contacts are hidden in the extensive body of mutational data that has been<br \/>\n&gt;accumulated over many years (e.g., [12-14] for the Escherichia coli lac<br \/>\n&gt;system). These measured repression values can be used as fitness landscapes, in<br \/>\n&gt;which pathways can be explored by computing consecutive rounds of single base<br \/>\n&gt;pair substitutions and selection. Here we develop this approach to study the<br \/>\n&gt;divergence of duplicate repressors and their binding sites. More specifically,<br \/>\n&gt;we focus on the creation of a new and unique protein-DNA recognition, starting<br \/>\n&gt;from two identical repressors and two identical operators. We consider<br \/>\n&gt;selective conditions that favor the evolution toward independent regulation.<br \/>\n&gt;Interestingly, such regulatory divergence is inherently a coevolutionary<br \/>\n&gt;process, where repressors and operators must be optimized in a coordinated<br \/>\n&gt;fashion.<br \/>\nThis is a gorgeous paper, and it shows how to do *good* math in the area of search-based modeling of evolution. Instead of the empty refrain of &#8220;it can&#8217;t work&#8221;, this paper presents a real model of a process, shows what it can do, and *makes predications* that can be empirically verified to match observations. This, folks, is how it *should* be done.<br \/>\n[migrations]: http:\/\/migration.wordpress.com\/2006\/07\/12\/duplication_and_coevolutionary_modeling\/<br \/>\n[dembski-nfl]: http:\/\/scienceblogs.com\/goodmath\/2006\/06\/dembski_and_no_free_lunch_with_2.php<br \/>\n[plos]: http:\/\/compbiol.plosjournals.org\/perlserv\/?request=get-document&amp;doi=10.1371\/journal.pcbi.0020058<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Via [Migrations][migrations], I&#8217;ve found out about a really beautiful computational biology paper that very elegantly demonstrates how, contrary to the [assertions of bozos like Dembski][dembski-nfl], an evolutionary process can adapt to a fitness landscape. The paper was published in the PLOS journal &#8220;Computational Biology&#8221;, and it titled [&#8220;Evolutionary Potential of a Duplicated Repressor-Operator Pair: Simulating [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[24],"tags":[],"class_list":["post-74","post","type-post","status-publish","format-standard","hentry","category-goodmath"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p4lzZS-1c","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/74","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/comments?post=74"}],"version-history":[{"count":0,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/74\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/media?parent=74"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/categories?post=74"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/tags?post=74"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}