Dataset Information

Alternative splicing expands the repertoire of dominant JAZ repressors of jasmonate signaling.

ABSTRACT: Jasmonates (JAs) are fatty acid-derived signaling compounds that control diverse aspects of plant growth, development and immunity. The F-box protein COI1 functions both as a receptor for jasmonoyl-l-isoleucine (JA-Ile) and as the component of an E3-ubiquitin ligase complex (SCF(COI1) ) that targets JAZ transcriptional regulators for degradation. A key feature of JAZ proteins is the C-terminal Jas motif that mediates the JA-Ile-dependent interaction with COI1. Here, we show that most JAZ genes from evolutionarily diverse plants contain a conserved intron that splits the Jas motif into 20?N-terminal and seven C-terminal (X(5) PY) amino acid submotifs. In most members of the Arabidopsis JAZ family, alternative splicing events involving retention of this intron generate proteins that are truncated before the X(5) PY sequence. In?vitro pull-down and yeast two-hybrid assays indicate that these splice variants have reduced capacity to form stable complexes with COI1 in the presence of the bioactive stereoisomer of the hormone (3R,7S)-JA-Ile. cDNA overexpression studies showed that some, but not all, truncated splice variants are dominant repressors of JA signaling. We also show that strong constitutive expression of an intron-containing JAZ10 genomic clone is sufficient to repress JA responses. These findings provide evidence for functional differences between JAZ isoforms, and establish a direct link between the alternative splicing of JAZ pre-mRNA and the dominant repression of JA signal output. We propose that production of dominant JAZ repressors by alternative splicing reduces the negative consequences associated with inappropriate or hyperactivation of the JA response pathway.

SUBMITTER: Chung HS

PROVIDER: S-EPMC2966510 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Alternative splicing expands the repertoire of dominant JAZ repressors of jasmonate signaling.

Chung Hoo Sun HS Cooke Thomas F TF Depew Cody L CL Patel Lalita C LC Ogawa Narihito N Kobayashi Yuichi Y Howe Gregg A GA

The Plant journal : for cell and molecular biology 20100801 4

Jasmonates (JAs) are fatty acid-derived signaling compounds that control diverse aspects of plant growth, development and immunity. The F-box protein COI1 functions both as a receptor for jasmonoyl-l-isoleucine (JA-Ile) and as the component of an E3-ubiquitin ligase complex (SCF(COI1) ) that targets JAZ transcriptional regulators for degradation. A key feature of JAZ proteins is the C-terminal Jas motif that mediates the JA-Ile-dependent interaction with COI1. Here, we show that most JAZ genes f ...[more]

PMID: 20525008

Similar Datasets

Project description:Jasmonate is an essential phytohormone regulating plant growth, development, and defense. Alternative splicing (AS) in jasmonate ZIM-domain (JAZ) repressors is well-characterized and plays an important role in jasmonate signaling regulation. However, it is unknown whether other genes in the jasmonate signaling pathway are regulated by AS. We explore the potential for AS regulation in three Arabidopsis genotypes (WT, jaz2, jaz7) in response to methyl jasmonate (MeJA) treatment with respect to: (a) differential AS, (b) differential miRNA targeted AS, and (c) AS isoforms with novel functions. AS events identified from transcriptomic data were validated with proteomic data. Protein interaction networks identified two genes, SKIP and ALY4 whose products have both DNA- and RNA-binding affinities, as potential key regulators mediating jasmonate signaling and AS regulation. We observed cases where AS alone, or AS and transcriptional regulation together, can influence gene expression in response to MeJA. Twenty-one genes contain predicted miRNA target sites subjected to AS, which implies that AS is coupled to miRNA regulation. We identified 30 cases where alternatively spliced isoforms may have novel functions. For example, AS of bHLH160 generates an isoform without a basic domain, which may convert it from an activator to a repressor. Our study identified potential key regulators in AS regulation of jasmonate signaling pathway. These findings highlight the importance of AS regulation in the jasmonate signaling pathway, both alone and in collaboration with other regulators.Significance statementBy exploring alternative splicing, we demonstrate its regulation in the jasmonate signaling pathway alone or in collaboration with other posttranscriptional regulations such as nonsense and microRNA-mediated decay. A signal transduction network model for alternative splicing in jasmonate signaling pathway was generated, contributing to our understanding for this important, prevalent, but relatively unexplored regulatory mechanism in plants.

Dataset Information

Alternative splicing expands the repertoire of dominant JAZ repressors of jasmonate signaling.

Publications

Alternative splicing expands the repertoire of dominant JAZ repressors of jasmonate signaling.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets