Project description:Little is known of the transcriptome of in vivo-grown pollen tubes, due to the difficulty of collection of pollen tubes elongating within the maternal gynoecium.We obtained the mRNAs undergoing translation (the translatome) of in vivo-grown pollen tubes from self-pollinated gynoecia of Arabidopsis thaliana(Col-0). Transgenic Arabidopsis plants (LAT52-HF-RPL18) harboring an epitope tagged ribosomal protein L18 driven by the pollen specific promoter (ProLAT52) were used for mRNA-ribosome complex isolation. After collection of polyribosomal (polysomal) complexes from self-pollinated (in vivo), unpollinated styles (buds), and in vitro-cultured pollen tubes, the actively translated mRNAs (the translatome) were purified, amplified to antisense RNA (aRNA). These aRNAs were hybridized to microarrays.Three independent biological replicates samples of aRNA from Bud, in vivo, and in vitro polysomal mRNA (translatomes) were hybridized to GeneChips to produce CEL files.
Project description:Little is known of the transcriptome of in vivo-grown pollen tubes, due to the difficulty of collection of pollen tubes elongating within the maternal gynoecium.We obtained the mRNAs undergoing translation (the translatome) of in vivo-grown pollen tubes from self-pollinated gynoecia of Arabidopsis thaliana(Col-0).
Project description:Pollen development from the microspore involves a series of coordinated cellular events, and the resultant mature pollen is specialized in function that it can quickly germinate and produces a polar-growth pollen tube derived from the vegetative cell to deliver two sperms for fertilization. Understanding the molecular program underlying pollen development and germination still remains a major challenge for plant biology. We used Affymetrix GeneChip Rice Genome Array to comprehensively analyzed the dynamic changes in the transcriptomes of rice pollen at five sequential developmental stages from microspores to germinated pollen. Among the 51,279 transcripts on the array, we found 25,062 pollen-preferential transcripts, among which 2,203 were development stage-enriched. The diversity of transcripts decreased greatly from microspores to mature and germinated pollen, whereas the number of stage-enriched transcripts displayed a U-type change, with the lowest at the bicellular pollen stage; and a transition of overrepresented stage-enriched transcript groups associated with different functional categories, which indicates a shift in gene expression program at the bicellular pollen stage. About 54% of the now-annotated rice F-box protein genes were expressed preferentially in pollen. The transcriptome profile of germinated pollen was significantly and positively correlated with that of mature pollen. Analysis of expression profiles and coexpressed features of the pollen-preferential transcripts related to cell cycle, transcription, the ubiquitin/26S proteasome system, phytohormone signalling, the kinase system and defense/stress response revealed five expression patterns, which are compatible with changes in major cellular events during pollen development and germination. A comparison of pollen transcriptomes between rice and Arabidopsis revealed that 56.6% of the rice pollen preferential genes had homologs in Arabidopsis genome, but 63.4% of these homologs were expressed, with a small proportion being expressed preferentially, in Arabidopsis pollen. Rice and Arabidopsis pollen had non-conservative transcription factors each. These results supply novel insights into the molecular program and key components of the regulatory network regulating pollen development and germination. KEYWORDS: rice (Oryza sativa L.), pollination and fertilization, stigma, molecular functions, signaling, microarray, stress response
Project description:Pollen tubes extend through pistil tissues and are guided to ovules where they release sperm for fertilization. Although pollen tubes can germinate and elongate in a synthetic medium, their trajectory is random and their growth rates are slower compared to growth in pistil tissues. Furthermore, interaction with the pistil renders pollen tubes competent to respond to guidance cues secreted by specialized cells within the ovule. The molecular basis for this potentiation of the pollen tube by the pistil remains uncharacterized. We used a surgical procedure to obtain large quantities of uncontaminated pollen tubes that grew through the pistil and defined their transcriptome by microarray analysis. We also characterized the transcriptome of in vitro-grown pollen tubes (for 0.5hours or 4hours) and dessicated mature pollen in Arabidopsis.
Project description:Pollen germination, along with pollen tube growth, is an essential process for the reproduction of flowering plants. The germinating pollen with tip-growth characteristics provides an ideal model system for the study of cell growth and morphogenesis. As an essential step towards a detailed understanding of this important process, the objective of this study was to comprehensively analyze the transcriptome changes during pollen germination and pollen tube growth. Using Affymetrix Arabidopsis ATH1 Genome Arrays, this study is the first to show the changes in the transcriptome from desiccated mature pollen grains to hydrated pollen grains and then to pollen tubes of Arabidopsis thaliana. The number of expressed genes, either for total expressed genes or for specifically expressed genes, increased significantly from desiccated mature pollen to hydrated pollen and again to growing pollen tubes, which is consistent with the finding that pollen germination and tube growth was significantly inhibited in vitro by a transcriptional inhibitor. The results of GO analyses showed that expression of genes related to cell rescue, transcription, signal transduction and cellular transport were significantly changed, especially for up-regulation, during pollen germination and tube growth, respectively. In particular, genes of the CaM/CML, CHX and Hsp families showed the most significant changes during pollen germination and tube growth. These results demonstrate that the overall transcription of genes, both in the number of expressed genes and in the levels of transcription, was increased. Furthermore, the appearance of many novel transcripts during pollen germination as well as tube growth indicates that these newly expressed genes may function in this complex process. SUBMITTER_CITATION: Yi Wang, Wen-Zheng Zhang, Lian-Fen Song, Jun-Jie Zou, Zhen Su, and Wei-Hua Wu. Transcriptome analyses show changes in gene expression to accompany pollen germination and tube growth in Arabidopsis. Plant Physiol. September 5, 2008; 10.1104/pp.108.126375 Experiment Overall Design: Three samples are analyzed in this experiment. They are desiccated mature pollen grains (MP), hydrated pollen grains (HP) and growing pollen tubes (PT) of Arabidopsis thaliana, respectively. Each sample has two biological replicates, so that there are 6 data sets of ATH1 array in this experiment.
Project description:Pollen germination, along with pollen tube growth, is an essential process for the reproduction of flowering plants. The germinating pollen with tip-growth characteristics provides an ideal model system for the study of cell growth and morphogenesis. As an essential step towards a detailed understanding of this important process, the objective of this study was to comprehensively analyze the transcriptome changes during pollen germination and pollen tube growth. Using Affymetrix Arabidopsis ATH1 Genome Arrays, this study is the first to show the changes in the transcriptome from desiccated mature pollen grains to hydrated pollen grains and then to pollen tubes of Arabidopsis thaliana. The number of expressed genes, either for total expressed genes or for specifically expressed genes, increased significantly from desiccated mature pollen to hydrated pollen and again to growing pollen tubes, which is consistent with the finding that pollen germination and tube growth was significantly inhibited in vitro by a transcriptional inhibitor. The results of GO analyses showed that expression of genes related to cell rescue, transcription, signal transduction and cellular transport were significantly changed, especially for up-regulation, during pollen germination and tube growth, respectively. In particular, genes of the CaM/CML, CHX and Hsp families showed the most significant changes during pollen germination and tube growth. These results demonstrate that the overall transcription of genes, both in the number of expressed genes and in the levels of transcription, was increased. Furthermore, the appearance of many novel transcripts during pollen germination as well as tube growth indicates that these newly expressed genes may function in this complex process.
Project description:Pollen tubes extend through pistil tissues and are guided to ovules where they release sperm for fertilization. Although pollen tubes can germinate and elongate in a synthetic medium, their trajectory is random and their growth rates are slower compared to growth in pistil tissues. Furthermore, interaction with the pistil renders pollen tubes competent to respond to guidance cues secreted by specialized cells within the ovule. The molecular basis for this potentiation of the pollen tube by the pistil remains uncharacterized. We used a surgical procedure to obtain large quantities of uncontaminated pollen tubes that grew through the pistil and defined their transcriptome by microarray analysis. We also characterized the transcriptome of in vitro-grown pollen tubes (for 0.5hours or 4hours) and dessicated mature pollen in Arabidopsis. Experiment Overall Design: Pollen and pollen tubes were collected as described in the protocols section for RNA extraction and hybridization on Affymetrix ATH1 Genechip microarrays.
Project description:Transcript profiling analysis of csn4-1 light grown mutant seedlings compared to wild type using Arabidopsis ATH1 GeneChip array Keywords: 7 day old light grown seedlings, wild type and mutant
Project description:Transcript profiling analysis of csn3-1, csn4-1 and csn5 (csn5a-2 csn5b) light grown and dark grown mutant seedlings compared to light grown and dark grown wild type using Arabidopsis ATH1 GeneChip array Keywords: mutant analysis, growth condition analysis