A comprehensive strategy for identifying long‐distance mobile peptides in xylem sap. (7th October 2015)

• Record Type: Journal Article
• Authors: Okamoto, Satoru; Suzuki, Takamasa; Kawaguchi, Masayoshi; Higashiyama, Tetsuya; Matsubayashi, Yoshikatsu
• Is Part Of: Plant journal. Volume 84:Number 3(2015:Nov.)
• Page Start: 611
• Page End: 620
• Publication Date: 2015-10-07
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.13015
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj13015-abs-0001"> <title>Summary</title> <p>There is a growing awareness that secreted pemediate organ‐to‐organ communication in higher plants. Xylem sap peptidomics is an effective but challenging approach for identifying long‐distance mobile peptides. In this study we developed a simple, gel‐free purification system that combines <italic>o</italic>‐chlorophenol extraction with HPLC separation. Using this system, we successfully identified seven oligopeptides from soybean xylem sap exudate that had one or more post‐transcriptional modifications: glycosylation, sulfation and/or hydroxylation. RNA sequencing and quantitative PCR analyses showed that the peptide‐encoding genes are expressed in multiple tissues. We further analyzed the long‐distance translocation of four of the seven peptides using gene‐encoding peptides with single amino acid substitutions, and identified these four peptides as potential root‐to‐shoot mobile oligopeptides. Promoter–GUS analysis showed that all four peptide‐encoding genes were expressed in the inner tissues of the root endodermis. Moreover, we found that some of these peptide‐encoding genes responded to biotic and/or abiotic factors. These results indicate that our purification system provides a comprehensive approach for effectively identifying endogenous small peptides and reinforce the concept that higher plants employ various peptides in root‐to‐shoot signaling.</p> </abstract>