{"id":163754,"date":"2013-10-06T15:05:18","date_gmt":"2013-10-06T18:05:18","guid":{"rendered":"http:\/\/revistapesquisa.fapesp.br\/?p=163754"},"modified":"2015-02-06T17:00:52","modified_gmt":"2015-02-06T19:00:52","slug":"ramifications-of-sugarcane-2","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/ramifications-of-sugarcane-2\/","title":{"rendered":"Ramifications of sugarcane"},"content":{"rendered":"

\"038-039_Cana_208\"<\/a>Published in June 2013<\/em><\/p>\n

Planting a sugarcane crop does not\u00a0involve seeds. Instead, pieces of\u00a0the plant’s stalk, known as the\u00a0culm, are used. Each fragment\u00a0generates a new plant as its lateral buds\u00a0develop. The genetics behind the architecture\u00a0of sugarcane is being unveiled\u00a0by a group of researchers led by agricultural\u00a0engineer Fabio Nogueira from\u00a0Universidade Estadual Paulista (Unesp)\u00a0in the city of Botucatu, in partnership\u00a0with bioinformaticist Renato Vicentini\u00a0from the University of Campinas (Unicamp).\u00a0In a study reported in the Journal\u00a0of Experimental Botany in May 2013,\u00a0the researchers showed that small RNA\u00a0molecules (sRNA) control gene silencing\u00a0and activation in these lateral buds,\u00a0known as axillary buds.<\/p>\n

\u201cEach segment of the culm has one or\u00a0two dormant axillary buds,\u201d Nogueira\u00a0explains. \u201cWhen you cut the culm, the\u00a0hormonal and metabolic balance changes,\u00a0causing the buds to sprout and produce\u00a0a new plant.\u201d The protagonists of\u00a0this phenomenon are RNA molecules\u00a0that serve as \u201con\/off switches\u201d for genes\u00a0(see Pesquisa FAPESP Issue No. 133<\/a>).\u00a0One example is microRNA 159, abundantly\u00a0present in dormant axillary buds,\u00a0which also contain large amounts of the\u00a0plant hormone abscisic acid. This microRNA\u00a0blocks the plant’s physiological\u00a0response to another hormone, gibberellic\u00a0acid, which stimulates cell proliferation.\u00a0When the plant is cut, a signal (as\u00a0yet unidentified) reduces the amount of\u00a0abscisic acid in the axillary buds, which\u00a0in turn reduces the effects of microRNA\u00a0159 and activates the gibberellic acid\u00a0signaling pathway.<\/p>\n

The origin of many of these small RNAs\u00a0that can influence hormonal signaling and\u00a0responses to stressful situations \u2014 such\u00a0as drought \u2014 may be mobile fragments\u00a0of plant DNA known as transposable elements.\u00a0Nogueira reached this conclusion\u00a0when he compared the RNA sequences\u00a0detected in his project with those in the\u00a0database produced by the research group\u00a0led by University of S\u00e3o Paulo (USP) biologist\u00a0Marie-Anne Van Sluys (see Pesquisa\u00a0FAPESP Issue No. 198<\/a>). According to\u00a0Nogueira, transposable elements associated\u00a0with small RNAs increase diversity and\u00a0control genome function. The association\u00a0between the two genetic entities does\u00a0not end there. \u201cSome transposable elements\u00a0are negatively regulated by small\u00a0RNAs, which serve as buffers to prevent\u00a0DNA modification,\u201d Nogueira notes. In\u00a0the case of sugarcane, protecting DNA\u00a0from change is important for maintaining\u00a0the properties of commercial varieties\u00a0developed to produce more sugar or\u00a0to flourish in less rainy areas.<\/p>\n

\u201cI sought basic knowledge with my\u00a0project, but this understanding is also\u00a0essential for the propagation and productivity\u00a0of sugarcane,\u201d Nogueira explains.\u00a0The plant’s architecture is central\u00a0to determining the intended purpose\u00a0of a given plantation. Sugarcane culms\u00a0with few ramifications are better for producing\u00a0sugar, whereas plants with more\u00a0lateral buds and more leaves generate\u00a0more biomass, the raw material used for\u00a0the manufacture of second-generation\u00a0ethanol. Knowing the genetic players\u00a0involved in controlling these characteristics\u00a0makes it possible to develop\u00a0markers for plant selection and can contribute\u00a0to the improvement of commercial\u00a0varieties. The importance of this\u00a0work was acknowledged by the 2012 edition\u00a0of the Top Ethanol awards; second\u00a0place in the academic works category\u00a0was awarded to Fausto Ortiz-Morea for\u00a0his master’s thesis, which generated the\u00a0paper recently published in the Journal\u00a0of Experimental Botany. An additional\u00a0publication by Nogueira’s team, published\u00a0in BMC Plant Biology in 2010,\u00a0won second place at the same awards\u00a0program in 2013.<\/p>\n

Nogueira’s work has yielded a catalogue\u00a0of active small RNA molecules (microtranscriptome)\u00a0from the axillary buds\u00a0of sugarcane, and has made it available to\u00a0other researchers. In collaboration with\u00a0a group from the Luiz de Queiroz School\u00a0of Agriculture (Esalq\/USP), Nogueira\u00a0is testing some of these RNAs on plant\u00a0models in order to observe their effects\u00a0on metabolism.<\/p>\n

The researcher celebrates being the\u00a0first to examine the genetic regulation\u00a0of sugarcane architecture, but he is actually\u00a0the pioneer of a broader field.\u00a0There are no studies on small RNA\u00a0activity in the axillary buds of other\u00a0plants because these structures are very\u00a0small and difficult to isolate. With axillary\u00a0buds that can be viewed with the\u00a0naked eye, have measurable hormonal\u00a0concentrations, and contain DNA and\u00a0RNA that can be extracted, sugarcane\u00a0has all the essential characteristics to\u00a0become a model organism for plant architecture\u00a0studies.<\/p>\n

Project
\n<\/strong>Isolation and characterization of microRNAs and their target genes in sugarcane (No. 2007\/58289-5)<\/a>; Grant Mechanism: <\/strong>Young Investigators Awards Program; Coordinator: <\/strong>Fabio Tebaldi Silveira Nogueira (IB\/Unesp); Investment: <\/strong>R$ 314,903.10 (FAPESP).<\/p>\n

Scientific article<\/em>
\nORTIZ-MOREA, F.A. et al<\/em>. Global analysis of the sugarcane\u00a0microtranscriptome reveals a unique composition of small\u00a0RNAs associated with axillary bud outgrowth<\/a>. Journal of\u00a0Experimental Botany<\/strong>. v. 64, n. 8, p. 2.307-20. May 2013.<\/p>\n","protected":false},"excerpt":{"rendered":"RNA molecules control lateral stem growth in sugarcane","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[159],"tags":[153,237],"coauthors":[95],"class_list":["post-163754","post","type-post","status-publish","format-standard","hentry","category-science","tag-agronomy","tag-genetics"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/163754","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=163754"}],"version-history":[{"count":0,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/163754\/revisions"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=163754"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=163754"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=163754"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=163754"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}