Project description:To uncover a suit of genes related to the consumer preferred flavours, whole RNA sequencing followed by de novo genome assembly was performed on extreme flavoured papaya varieties RB1 (preferred with sweet flavour and floral aroma) and 1B (non-preferred with bitter flavour and musty aroma) fruits at ripe and unripe stages. We then performed gene expression profiling analysis using data obtained from RNA-seq of 2 different papaya varieties at ripe and unripe stages.
Project description:For identifying genes for sex determination in papaya, digital gene expression analysis by Ht-SuperSAGE (Matsumura et al., 2010) was carried out in flowers from male, female and hermaphrodite plants of papaya. Total more than 9,273,744 26bp-tags were obtained by sequence analysis using SOLiD3 and mapped on papaya primitive sex chromosome sequences.
Project description:For identifying genes for sex determination in papaya, digital gene expression analysis by Ht-SuperSAGE (Matsumura et al., 2010) was carried out in flowers from male, female and hermaphrodite plants of papaya. Total more than 9,273,744 26bp-tags were obtained by sequence analysis using SOLiD3 and mapped on papaya primitive sex chromosome sequences. 6 samples examined: male young flowerbud, male mature flower bud, female young flower bud, female mature flower bud, hermaphrodite young flower bud, hermaphrodite mature flower bud
Project description:The Babaco Mosaic Virus (BabMV) is a Potexvirus that affects babaco (Vasconcellea heilbornii) and papaya (Carica papaya) plants. To understand the impact of the virus on the plant, we performed a genome-wide transcriptome analysis of the response of young leaves of 3-4 months old papaya plants at 2, 10, 15- and 30-days post infection (dpi) in comparison to uninfected controls. Results showed that in mock-infected plants and virus-infected plants at 2 and 10dpi more than 90% of the reads mapped to the papaya genome. In contrast, at 15 and 30 dpi only 31% mapped to the papaya genome in BabMV infected leaves, while the remaining 69% of the reads aligned to the virus genome, demonstrating a high viral load. A total of 1585 papaya genes were differentially expressed between mock and BabMV inoculated leaves, among which cell wall biogenesis, redox signaling, and ribosome Gene Ontology terms were overrepresented, interestingly, the virus induced specific responses at different time points. Sugar metabolism and cell wall modification including lignin accumulation genes were affected at 15 dpi. At 30 days post-infection, the virus primarily induced ROS production, possibly through the activation of cytochrome P450 enzymes. This led to the upregulation of genes associated with ROS scavenging and of transcription factors (TFs) belonging to the WRKY and AP2/ERF families, which play crucial roles in activating the plant's defense mechanisms against viral pathogens. This research enhances our understanding of BabMV infections, facilitating the development of effective disease control measures.
Project description:Background: Papaya (Carica papaya L.) is a commercially important crop that produces climacteric fruits with a soft and sweet pulp that contain a wide range of health promoting phytochemicals. Despite its importance, little is known about transcriptional modifications during fruit ripening and its control. In this study we report the analysis of ripe papaya transcriptome by using a cross-species (XSpecies) microarray technique based on the phylogenetic proximity between papaya and Arabidopsis thaliana. Results: Papaya transcriptome analyses resulted in the identification of 414 ripening-related genes and some of them had their expression validated by qPCR. The transcription profile was then compared with that from ripening tomato and grape. Overall, the transcriptomics analysis revealed many similarities between ripening in papaya and tomato especially with respect to primary metabolism, regulation of transcription, biotic and abiotic stress and cell wall metabolism. XSpecies microarray data indicate that transcription factors (TFs) of the MADS-box, NAC and AP2/ERF gene families are involved in the control of papaya ripening and reveal that cell wall-related gene expression in papaya showed similarities to the expression profiles seen in A. thaliana during hypocotyl development. Conclusion: The cross-species array experiment was successful in identifying ripening-related genes in papaya. The data indicated common and diverse elements of transcription control between fruit bearing taxa and has also indicated a possible distinct co-evolutionary mechanism for papaya cell wall disassembling system. The present study represents new topics for future researches that would help complement the structural genomic data provided by the papaya genome, since there is no gene-chip available for this plant organism. Papaya ripe transcriptome was analysed using mRNA extracted from unripe and ripe fruit from 2 replicates. After microarray hybridization in ATH1-121501 chip, data were normalized against data generated by papaya DNA hybridization in another ATH1-121501 chip and analysed using perl algorithms (masks).