ABSTRACT\n\n Plants systemically regulate growth and gene expression according to their internal nitrate status. Our previous study reported that shoot nitrate accumulation increases shoot expression of adenosine phosphate\u2010 ISOPENTENYLTRANSFERASE 3 ( IPT3 ) and shoot levels of N 6<\/sup> \u2010(\u0394 2<\/sup> \u2010isopentenyl) adenine (iP)\u2010type cytokinins (CKs). IPT3 expression is localized in the phloem, and iP\u2010type CKs, which are synthesized by IPT3, are phloem\u2010mobile. As CKs are a class of phytohormones that control growth and genome\u2010wide gene expression, shoot\u2010expressed IPT3 may mediate the systemic regulation of growth and transcriptomic responses to shoot nitrate status. To examine this, we developed a novel system to manipulate nitrate levels and IPT3 expression in a shoot\u2010specific manner and performed growth analysis, CK determination, and RNA\u2010sequencing. Our results demonstrated that shoot nitrate accumulation significantly promoted shoot growth and elevated shoot concentrations of iP ribotides, iP\u20107\u2010 N \u2010glucoside, and iP\u20109\u2010 N \u2010glucoside through the action of shoot IPT3. Transcriptomic responses to shoot nitrate accumulation were largely tuned by shoot IPT3, with opposite effects in shoots and roots. Shoot IPT3 amplified shoot responses of nitrate\u2010inducible genes and immune response genes to shoot nitrate accumulation, while it dampened root responses of nitrate transport\/assimilation genes. This transcriptomic modulation via shoot IPT3 was accompanied by coherent transcriptional changes in genes encoding mobile peptides and transcriptional repressors. Here we present a novel scheme integrating shoot nitrate status responses with CK signaling.<\/p>","protected":false},"excerpt":{"rendered":"Kota Monden, Takamasa Suzuki, Mikiko Kojima, Yumiko Takebayashi, Daisuke Sugiura, Tsuyoshi Nakagawa, Hitoshi S […]","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-3549","post","type-post","status-publish","format-standard","hentry","category-article"],"_links":{"self":[{"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/posts\/3549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/comments?post=3549"}],"version-history":[{"count":0,"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/posts\/3549\/revisions"}],"wp:attachment":[{"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/media?parent=3549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/categories?post=3549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/biochemistry.isc.chubu.ac.jp\/labo\/suzuki\/wp-json\/wp\/v2\/tags?post=3549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}