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Abstract

Jasmonate (JA) is a signaling compound essential for anther development and pollen fertility in Arabidopsis. Mutations that block the pathway of JA synthesis result into male sterility. To understand the processes of anther and pollen maturation, we used microarray and differential display approaches to compare gene expression pattern in anthers of wild-type Arabidopsis and the male-sterile mutant, opr3. Microarray experiment revealed 25 genes that were up-regulated more than 1.8-fold in wild-type anthers as compared to mutant anthers. Experiments based on differential display identified 13 additional genes up-regulated in wild-type anthers compared to opr3 for a total of 38 differentially expressed genes. Searches of the Arabidopsis and non-redundant databases disclosed known or likely functions for 28 of the 38 genes identified, while 10 genes encode proteins of unknown function. Northern blot analysis of eight representative clones as probes confirmed low expression in opr3 anthers compared with wild-type anthers. JA responsiveness of these same genes was also investigated by northern blot analysis of anther RNA isolated from wild-type and opr3 plants, In these experiments, four genes were induced in opr3 anthers within 0.5-1 h of JA treatment while the remaining genes were up-regulated only 1-8 h after JA application. None of these genes was induced by JA in anthers of the coil mutant that is deficient in JA responsiveness. The four early-induced genes in opr3 encode lipoxygenase, a putative bHLH transcription factor, epithiospecifier protein and an unknown protein. We propose that these and other early components may be involved in JA signaling and in the initiation of developmental processes. The four late genes encode an extensin-like protein, a peptide transporter and two unknown proteins, which may represent components required later in anther and pollen maturation. Transcript profiling has provided a successful approach to identify genes involved in anther and pollen maturation in Arabidopsis.

Regulation and function of specifier proteins in plants

“…Similarly, microarray analysis of anthers of the Ws ecotype revealed a 5-fold increase in ESP transcript after spraying with JA (Mandaokar et al 2003). The latter result was further confirmed by differential display RT-PCR and Northern Blot analysis.…”

“…Application of JA itself resulted in an induction of ESP in rosette leaves of the Col-0 ecotype after only 2 h as shown in Northern Blot experiments with plants of different ages (Miao and Zentgraf 2007). No ESP transcript was detected in the JA-insensitive coi1 mutant (treated or untreated) which further supports the impact of JA on ESP transcript accumulation (Mandaokar et al 2003).…”

The Jasmonate-ZIM Domain Proteins Interact with the R2R3-MYB Transcription Factors MYB21 and MYB24 to Affect Jasmonate-Regulated Stamen Development in Arabidopsis

“…JA-deficient mutants fad3 fad7 fad8 (McConn and Browse, 1996), dad1 (Ishiguro et al, 2001), aos (Park et al, 2002), and opr3/dde1 (Sanders et al, 2000;Stintzi and Browse, 2000;Mandaokar et al, 2003) are male sterile due to short stamen filament, failure of anther dehiscence, and unviable pollens. Application of exogenous jasmonic acid can restore the male fertility of the JA-deficient mutants.…”

Genome-Wide Transcriptome Profiling Revealed Cotton Fuzz Fiber Development Having a Similar Molecular Model as Arabidopsis Trichome

“…GhHOX1 was able to restore the glabrous phenotype of gl2 mutant, indicating that this protein is a functional homologue of GL2 in controlling trichome development and may function in fiber development [30]. Two GL3-like bHLH cDNAs from cotton ovule, GhDEL65 and GhDEL61 , have been deposited in the Genbank [31], [32]. It will be interesting to examine if they work like GL3 during cotton fiber development.…”