CLE6 expression recovers gibberellin deficiency to promote shoot growth in Arabidopsis. (26th March 2014)

• Record Type: Journal Article
• Authors: Bidadi, Haniyeh; Matsuoka, Keita; Sage‐Ono, Kimiyo; Fukushima, Jun; Pitaksaringkarn, Weerasak; Asahina, Masashi; Yamaguchi, Shinjiro; Sawa, Shinichiro; Fukuda, Hiroo; Matsubayashi, Yoshikatsu; Ono, Michiyuki; Satoh, Shinobu
• Is Part Of: Plant journal. Volume 78:Number 2(2014:Apr.)
• Page Start: 241
• Page End: 252
• Publication Date: 2014-03-26
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12475
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12475-abs-0001"> <title>Summary</title> <p>Small peptides act as local signals during plant development, but few studies have examined their interaction with phytohormone signaling. Here, we show that application of gibberellin (GA) to Arabidopsis shoots induces substantial accumulation of transcripts encoded by <italic>CLE6</italic>, a member of the <italic>CLAVATA</italic>/<italic>ESR‐RELATED</italic> (<italic>CLE</italic>) gene family, in the root stele, followed by promotion of organ growth by <italic>CLE6</italic> in GA‐deficient plants. The long‐distance effect of GA<sub>4</sub> was demonstrated by the observation that its application to the shoot apex of the GA‐deficient mutant <italic>ga3ox1</italic>/<italic>ga3ox2</italic> rescued the short–root phenotype. Microarray analysis was used to identify root‐expressed genes that respond to systemic application of GA, and <italic>CLE6</italic> was selected for further analysis. <italic>CLE6</italic> was highly expressed in roots at the young seedling stage, and <italic>CLE6</italic> promoter activity was strong in hypocotyls and roots, especially in root stele cells at branch points. Application of CLE6 peptide had no obvious effect on the growth and development of GA‐deficient mutant plants. Nonetheless, the fact that ectopic over‐expression of <italic>CLE6</italic> in the GA‐deficient mutant promoted root growth and branching, petiole elongation, bolting rate and stem length showed that <italic>CLE6</italic> expression partially compensates for the GA deficiency. Reciprocal grafting of GA‐deficient mutant plants to <italic>35S::CLE6</italic> transformants complemented the shoot phenotype associated with GA deficiency, demonstrating the systemic effect of CLE6 from root to shoot. These data suggest that root‐expressed <italic>CLE6</italic> is systemically involved in shoot growth under GA action in Arabidopsis.</p> </abstract>