XTH20 and XTH19 regulated by ANAC071 under auxin flow are involved in cell proliferation in incised Arabidopsis inflorescence stems. (1st October 2014)

• Record Type: Journal Article
• Authors: Pitaksaringkarn, Weerasak; Matsuoka, Keita; Asahina, Masashi; Miura, Kenji; Sage‐Ono, Kimiyo; Ono, Michiyuki; Yokoyama, Ryusuke; Nishitani, Kazuhiko; Ishii, Tadashi; Iwai, Hiroaki; Satoh, Shinobu
• Is Part Of: Plant journal. Volume 80:Number 4(2014:Nov.)
• Page Start: 604
• Page End: 614
• Publication Date: 2014-10-01
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12654
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12654-abs-0001"> <title>Summary</title> <p>One week after partial incision of <italic>Arabidopsis</italic> inflorescence stems, the repair process in damaged tissue includes pith cell proliferation. Auxin is a key factor driving this process, and <italic>ANAC071</italic>, a transcription factor gene, is upregulated in the distal region of the incised stem. Here we show that <italic>XTH20</italic> and the closely related <italic>XTH19</italic>, members of xyloglucan endotransglucosylase/hydrolases family catalyzing molecular grafting and/or hydrolysis of cell wall xyloglucans, were also upregulated in the distal part of the incised stem, similar to <italic>ANAC071</italic>. <italic>XTH19</italic> was expressed in the proximal incision region after 3 days or after auxin application to the decapitated stem. Horizontal positioning of the plant with the incised side up resulted in decreased <italic>Pro</italic><sub><italic>DR</italic></sub><sub><italic>5</italic></sub><italic>:GUS</italic>, <italic> ANAC071</italic>, <italic> XTH20</italic>, and <italic>XTH19</italic> expression and reduced pith cell proliferation. In incised stems of <italic>Pro</italic><sub><italic>35S</italic></sub><italic>:ANAC071‐SRDX</italic> plants, expression of <italic>XTH20</italic> and <italic>XTH19</italic> was substantially and moderately decreased, respectively. <italic>XTH20</italic> and <italic>XTH19</italic> expression and pith cell proliferation were suppressed in <italic>anac071</italic> plants and were increased in <italic>Pro</italic><sub><italic>35S</italic></sub><italic>:ANAC071</italic> plants. Pith cell proliferation was also inhibited in the <italic>xth20xth19</italic> double mutant. Furthermore, ANAC071 bound to the <italic>XTH20</italic> and <italic>XTH19</italic> promoters to induce their expression. This study revealed <italic>XTH20</italic> and <italic>XTH19</italic> induction by auxin via ANAC071 in the distal part of an incised stem and their involvement in cell proliferation in the tissue reunion process.</p> </abstract>