Project description:Heatwaves resulting from global warming are a leading threat to plants because they specifically impair reproductive (gametophytic) development. We investigated pollen development using proteomics after exposure to heat (38/28 °C; day/night). Sampling enabled the identification of the impact of heat on gene products in tetrads (immediately post-meiosis), uninucleate and binucleate microspores (early mitosis), and mature pollen. A library consisting of 5257 G. hirsutum proteins was constructed using SWATH-MS, which led to quantification of 4501 proteins at the four distinct stages. Data analysis revealed that 880, 360, 307 and 166 proteins were differentially expressed when the tetrad, uninucleate, binucleate and mature pollen stages, respectively, were subjected to heat. Surprisingly, most of these DEPs were identified only at a single developmental stage, indicating translation of stage-specific proteins in response to heat. Especially, high numbers of differentially expressed proteins (DEPs) were identified in tetrads compared with the late developmental stages; these were mainly associated with protein processing in endoplasmic reticulum, oxidative phosphorylation, spliceosome, cytoskeletal response, chaperones and folding catalysts, carbon metabolism and membrane trafficking. We conclude that protein synthesis in tetrad cells responded acutely to heat by supplying cellular components that enable subsequent mitosis and structural changes in the haploid germ cells leading the mature pollen. We hypothesise that fewer DEPs at the later stages might reflect a lower sensitivity to high temperatures. Identifying the stage-specific proteins will lead to the identity of key heat-responsive genes and new genetic tools for improved resilience of all seed and fruit-based crops as climates keep warming.
Project description:The development of viable gametes is especially susceptible to heat in all higher plants, including cotton (Gossypium hirsutum cv. Sicot 71), resulting in substantial reduction in lint quantity and quality at temperatures above 32 °C. Male reproductive cells are especially vulnerable to heat. This study demonstrates a relatively small impact of heat on leaves compared with a profound impact during early and late male gametophyte development. To investigate the mechanisms leading to heat sensitivity, the proteome of pollen was analyzed after two distinct phases of development (tetrads or binucleate microspores) had been exposed for 5 d to 36/25 °C (day/night) or 40/30 °C. The resulting mature pollen grains were collected for quantitative label-free shotgun proteomic analysis. A total of 868 proteins was quantified. Interestingly, Hsp70s were highly induced in response to extreme heat indicating key roles of this family to cope with heat stress.
Project description:This SuperSeries is composed of the following subset Series: GSE29566: Global gene expression analysis of cotton (Gossypium hirsutum L.) under drought stress in leaf tissue. GSE29567: Global gene expression analysis of cotton (Gossypium hirsutum L.) under drought stress during fibre development stages. Refer to individual Series
Project description:Purpose: The goal of this experiment was to use RNA-seq to compare the two commercial cotton species Gossypium hirsutum and Gossypium barbadense and determine what transcripts may account for the better fiber quality in the latter. Methods: RNA was extracted from Gossypium barbadense or Gossypium hirsutum fibers at 10, 15, 18, 21, and 28 days post anthesis. Paired-end, 100-bp RNA-seq was performed on an Illumina HiSeq2000 and the reads were mapped to the Gossypium raimondii genome at www.phytozome.net and non-homologous contig assemblies from Gossypium arboreum. Results from RNA-seq were combined with non-targeted metabolomics. Results: Approximately 38,000 transcripts were expressed (RPKM>2) in each fiber type and approximately 2,000 of these transcripts were differentially expressed in a cross-species comparison at each timepoint. Enriched Gene Ontology biological processes in differentially expressed transcripts suggested that Gh fibers were more stressed. Conclusions: Both metabolomic and transcriptomic data suggest that better mechanisms for managing reactive oxygen species contribute to the increased fiber length in Gossypium barbadense. This appears to result from enhanced ascorbate biosynthesis via gulono-1,4-lactone oxidase and ascorbate recycling via dehydroascorbate reductase.
Project description:Purpose: The goal of this experiment was to use RNA-seq to compare the two commercial cotton species Gossypium hirsutum and Gossypium barbadense and determine what transcripts may account for the better fiber quality in the latter. Methods: RNA was extracted from Gossypium barbadense or Gossypium hirsutum fibers at 10, 15, 18, 21, and 28 days post anthesis. Paired-end, 100-bp RNA-seq was performed on an Illumina HiSeq2000 and the reads were mapped to the Gossypium raimondii genome at www.phytozome.net and non-homologous contig assemblies from Gossypium arboreum. Results from RNA-seq were combined with non-targeted metabolomics. Results: Approximately 38,000 transcripts were expressed (RPKM>2) in each fiber type and approximately 2,000 of these transcripts were differentially expressed in a cross-species comparison at each timepoint. Enriched Gene Ontology biological processes in differentially expressed transcripts suggested that Gh fibers were more stressed. Conclusions: Both metabolomic and transcriptomic data suggest that better mechanisms for managing reactive oxygen species contribute to the increased fiber length in Gossypium barbadense. This appears to result from enhanced ascorbate biosynthesis via gulono-1,4-lactone oxidase and ascorbate recycling via dehydroascorbate reductase. See Bioproject PRJNA263926 and SRA accession SRP049330 for study design and raw sequencing data and Bioproject PRJNA269608 and TSA accession GBYK00000000 for Gossypium arboreum assembled contig sequences used for transcriptome mapping - Cotton fiber mRNA from 10,15,18,21 and 28 day post anthesis fiber from either Gossypium hirusutm or Gossypium barbadense was sequenced and differential gene expression analysis was conducted between species for each timepoint and between adjacent timepoints. Each timepoint was representative of fiber from 9 individual plants processed as 3 biological replicate pools (material from 3 individual plants per pool).
Project description:Each plant's architecture, composed of patterns of indeterminate and determinate growth, is defined through the activities of meristems. Understanding the regulation of meristem identity can benefit plant architecture and crop yield. To understand how meristem activities contribute to different architectures in cotton (Gossypium hirsutum), we used RNA-Seq to determine the transcriptomes from meristems isolated from different developmental stages of wild photoperiodic and domesticated day-neutral cotton grown under different photoperiods.