ScRALF3, a secreted RALF‐like peptide involved in cell–cell communication between the sporophyte and the female gametophyte in a solanaceous species. (25th February 2013)

• Record Type: Journal Article
• Authors: Chevalier, Eric; Loubert‐Hudon, Audrey; Matton, Daniel P.
• Is Part Of: Plant journal. Volume 73:Number 6(2013:Mar.)
• Page Start: 1019
• Page End: 1033
• Publication Date: 2013-02-25
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12096
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" xml:lang="en" id="tpj12096-abs-0001"> <title>Summary</title> <p>Small peptides have been shown to regulate numerous aspects of plant development through cell–cell communication. These signaling events are particularly important during reproduction, regulating gamete development and embryogenesis. Rapid alkalinization factor (RALF)<italic>‐like</italic> genes, a large gene family that encodes secreted peptides, have specific or ubiquitous expression patterns. Previously, five <italic>RALF‐like</italic> genes with potential involvement during reproduction were isolated from <italic>Solanum chacoense</italic>. Here, we show that ScRALF3 is an important peptide regulator of female gametophyte development. Its expression, which is auxin‐inducible, is strictly regulated before and after fertilization. Down‐regulation of <italic>ScRALF3</italic> expression by RNA interference leads to the production of smaller fruits that produce fewer seeds, due to improper development of the embryo sacs. Defects include loss of embryo sac nuclei polarization, as well as an increase in asynchronous division, accounting for cellular dysfunctions and premature embryo sac development arrest during megagametogenesis. <italic>ScRALF3</italic> is expressed in the sporophytic tissue surrounding the embryo sac, the integument and the nucellus, as revealed by <italic>in situ</italic> hybridization and GUS staining. As expected for a secreted peptide, fluorescence from an ScRALF3–GFP fusion construct is detected throughout the secretory pathway. Therefore, the ScRALF3 secreted peptide may be directly involved in the regulation of multiple aspects of cell–cell communication between the female gametophyte and its surrounding sporophytic tissue during ovule development.</p> </abstract>