Project description:RNA-directed DNA methylation (RdDM) in plants is a well-characterized example of RNA interference-related transcriptional gene silencing. To determine the relationships between RdDM and heterochromatin in the repeat-rich maize (Zea mays) genome, we performed whole-genome analyses of several heterochromatic features: dimethylation of lysine 9 and lysine 27 (H3K9me2 and H3K27me2), chromatin accessibility, DNA methylation, and small RNAs; we also analyzed two mutants that affect these processes, mediator of paramutation1 and zea methyltransferase2.
Project description:The Helicoverpa armigera single-capsid nucleopolyhedrovirus (HaSNPV) can be propagated using H. zea insect cell cultures, for use as a biopesticide against Heliothine agricultural pests.This study sequenced, assembled and functionally annotated 29,586 transcript sequences from cultured H. zea cells using Illumina 100 bps and paired-end transcriptome sequencing (RNA-seq). From these sequences, a genome-scale microarray platform was constructed and validated for effective expression analysis of H. zea genes. This array also included probes for all HaSNPV genes, thereby allowing virus and host gene changes to be monitored simultaneously.
Project description:Genetic relationship of a newly discovered teosinte from Nicaragua, Zea nicaraguensis with waterlogging tolerance, was determined based on randomly amplified polymorphic DNA (RAPD) markers and the internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA using 14 accessions from Zea species. RAPD analysis showed that a total of 5,303 fragments were produced by 136 random decamer primers, of which 84.86% bands were polymorphic. RAPD-based UPGMA analysis demonstrated that the genus Zea can be divided into section Luxuriantes including Zea diploperennis, Zea luxurians, Zea perennis and Zea nicaraguensis, and section Zea including Zea mays ssp. mexicana, Zea mays ssp. parviglumis, Zea mays ssp. huehuetenangensis and Zea mays ssp. mays. ITS sequence analysis showed the lengths of the entire ITS region of the 14 taxa in Zea varied from 597 to 605 bp. The average GC content was 67.8%. In addition to the insertion/deletions, 78 variable sites were recorded in the total ITS region with 47 in ITS1, 5 in 5.8S, and 26 in ITS2. Sequences of these taxa were analyzed with neighbor-joining (NJ) and maximum parsimony (MP) methods to construct the phylogenetic trees, selecting Tripsacum dactyloides L. as the outgroup. The phylogenetic relationships of Zea species inferred from the ITS sequences are highly concordant with the RAPD evidence that resolved two major subgenus clades. Both RAPD and ITS sequence analyses indicate that Zea nicaraguensis is more closely related to Zea luxurians than the other teosintes and cultivated maize, which should be regarded as a section Luxuriantes species.
Project description:This is a cell culture based study to asses the impact of ZEA (Zearalenone) and E. coli co-contamination on IPEC cells, these is a normal epithelial cell line isolated from a new born piglet. ZEA is a mycotoxin with a negative impact in human health. The microarray is a custom Agilent Technology array slide with the AMAID: 05685.
