Aarhus University<\/a> combined structural biology, which reveals the three-dimensional shape of proteins, with biochemistry and experiments in living plants to investigate the receptors that detect chitin at the surface of plant root cells.<\/p>\nThey discovered that a receptor called CHIP13 binds long chitin chains much more strongly than short ones.<\/p>\n
![\"Plants](\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAADCAQAAAAe\/WZNAAAAEElEQVR42mM8U88ABowYDABAxQPltt5zqAAAAABJRU5ErkJggg==\")
<\/p>\n
Kira Gysel at Aarhus University. (Emma Steer via SWNS)<\/p>\n
By Talker<\/p>\n
A distinctive part of the receptor \u2014 which the team calls the \u201cbridge domain\u201d \u2014 helps it grip the chain at several points, so that only chains long enough to span them are held tightly.<\/p>\n
Study co-leader assistant professor Kira Gysel says the bridge domain is a \u201challmark\u201d of a whole class of related receptors.<\/p>\n
Gysel said: \u201cThe central question was how plants tell long chitin chains from short ones.<\/p>\n
\u201cWe learned that CHIP13, and specifically its bridge domain, works like a measuring tape.<\/p>\n
\u201cThat allows the plant to recognize signals associated specifically with a potential fungal attack and not confuse them with signals from potentially helpful microbes.\u201d<\/p>\n
She says plants also depend on a second receptor, called CERK6, to respond to chitin.<\/p>\n
Gysel and her colleagues investigated how the two receptors work together.<\/p>\n
The research team found that in the presence of chitin, CHIP13 recruits CERK6, and the two form a signaling complex that activates the plant\u2019s immune system, with a clear division of labor between the two proteins.<\/p>\n
Experiments in which either receptor was blocked confirmed that the plant needs both to mount a defense response.<\/p>\n
Gysel said: \u201cCHIP13 can recognize or \u2018see\u2019 the long chitin fragments associated with dangerous fungi in the soil.<\/p>\n
<\/p>\n
(Photo by ayana durand via Pexels)<\/p>\n
By Talker<\/p>\n
\u201cIt then physically comes together with CERK6, and only CERK6 can sound the alarm for the rest of the plant.<\/p>\n
\u201cBoth proteins have very specific jobs, and both are needed for this core pillar of the plant immune system.\u201d<\/p>\n
Study co-first author Simon Boje Hansen said: \u201cWe were facing a puzzle: how can CERK6 be essential for the plant\u2019s response to chitin, when it can barely hold on to it?<\/p>\n
\u201cIt turns out the two receptors split the work: one recognizes the signal, the other passes it on.<\/p>\n
\u201cNeither can do the job alone.\u201d<\/p>\n
Study co-first author Henriette R\u00fcbsam said: \u201cWe could see this directly in plants too.<\/p>\n
\u201cIt was only when chitin was bound to CHIP13 that CHIP13 could call on CERK6.<\/p>\n
\u201cImportantly, we saw that this was also true in a second legume plant, showing that this mechanism is preserved across different species.\u201d<\/p>\n
Gysel says the research is more than just discovering the structure and mechanism of the proteins.<\/p>\n
She said it provides valuable new insights into how plants perceive their environment and protect themselves from biological threats in soil.<\/p>\n
Gysel added: \u201cThis research is a window into the complex pattern recognition system that plants use to interpret the microbial world surrounding them.<\/p>\n
\u201cIf we can better understand this, we can start to think about designing receptors that read new signals altogether, expanding what plants are capable of sensing and responding to.\u201d<\/p>\n
She says the insight could help guide efforts to improve crop resilience<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Light microscopy image of crystallised CHIP13 protein. (Kira Gysel via SWNS) By Talker By Stephen Beech Plants use…\n","protected":false},"author":2,"featured_media":647748,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[85,46,141,39020],"class_list":["post-647747","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-il","tag-israel","tag-science","tag-stephen-beech"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/647747","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=647747"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/647747\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/647748"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=647747"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=647747"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=647747"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}