Project description:Highly rearranged and mutated cancer genomes present major challenges in the identification of pathogenetic events driving the cancer process. Here, we engineered lymphoma-prone mice with chromosomal instability to assess the utility of mouse models in cancer gene discovery and the extent of cross-species overlap in cancer-associated copy number aberrations. Integrating with targeted re-sequencing, our comparative oncogenomic studies efficiently identified FBXW7 and PTEN as commonly deleted or mutated tumor suppressors in human T-cell acute lymphoblastic leukemia/lymphoma (T-ALL). More generally, the murine cancers acquire widespread recurrent clonal amplifications and deletions targeting loci syntenic to alterations present in not only human T-ALL but also diverse tumors of hematopoietic, mesenchymal and epithelial types. These results thus support the view that murine and human tumors experience common biological processes driven by orthologous genetic events as they evolve towards a malignant phenotype. The highly concordant nature of genomic events encourages the use of genome unstable murine cancer models in the discovery of biologically relevant driver events in human cancer. Keywords: comparative genomic hybridization
Project description:The closely related Coffea arabica cultivars ‘Tall Mokka’ and ‘Typica’, with excellent flavor, but differing distinctively in the size of aerial organs, branching pattern and branch numbers. Differential gene expression analysis of shoot tips of arabica coffee cultivars 'Tall Mokka' and 'Typica' were done using Potato cDNA microarray as cross-species platform. Using cross-species microarray hybridization, we identified a prolyl oligopeptidase (CaPOP) gene as differentially expressed between the shoot tips of ‘Tall Mokka’ and ‘Typica’. Isolation and sequencing of POP genes from coffee identified three paralogs, CaPOP1, CaPOP2 and CaPOP3. All three genes were present in both cultivars, which suggest that differences in the expression of CaPOP are caused by factor(s) regulating the transcription of CaPOPs. CaPOP1 differs in sequence from CaPOP2 primarily in having two large deletions in the promoter region. CaPOP genes are homologous to arabidopsis At1g20380, encoding a post-proline cleaving enzyme that acts on substrates shorter than 30 amino acids. Ectopic expression of CaPOP1 under its native promoter in transgenic arabidopsis resulted in more secondary branches than in the wild type. This is the first study to successfully isolate CaPOP genes and characterize their expression in the developing tissues of coffee. This study also identified a novel role for prolyl oligopeptidase in control of branching. Eight coffee trees of 'Typica' ('K') and six trees of 'Tall Mokka' ('M') cultivar were used in this study. The trees were equally divided into two groups 'A' and 'B' for each cultivar ('MA','MB', 'KA' and 'KB') and treated as biological replicates. Eight two channel microarray hybridizations were done in following pairs: MA x KA, MA x KB, MB x KA, MB x KB and dye swap replicate of each pair. Summary: Two-sample experiment: Tall Mokka vs. Typica . 8 Hybridizations. 2 Biological replicates per sample. 1 Dye swap per array.
Project description:Purpose: We aimed to dissect heat response of tall fescue and possible roles of melatonin and 24-epibrassinolide during thermotolerance. Methods: A total amount of 3 µg RNA was used for generation of sequencing libraries using NEBNext® Ultra™ RNA Library Prep Kit for Illumina® (NEB, USA) following manufacturer’s recommendations and index codes were added to attribute sequences to each sample. After cluster generation, the library preparations were sequenced on an Illumina Hiseq platform and 125 bp/150 bp paired-end reads were generated. Clean reads were obtained by removing low quality reads, reads containing adapter and ploy-N from raw data. At the same time, Q20, Q30 and GC content the clean data were calculated. Index of the Arabidopsis genome was built using Bowtie v2.2.3 and paired-end clean reads were aligned to the reference genome using TopHat v2.0.12. HTSeq v0.6.1 was used to count the reads numbers mapped to each gene. And then FPKM (Fragments Per Kilobase of transcript sequence per Millions base pairs sequenced) of each gene was calculated based on the length of the gene and reads count mapped to this gene. Differential expression analysis of drought stress versus control condition was performed using the DESeq R package (1.18.0). Results:In total, six samples with two biological replicates per genotype/treatment combination were used for RNA sequencing analysis. At least 2 G clean bases were generated for each sample. Comparative analysis identified genes modulated by short term heat (2h) and long term heat (12h) treatments.