Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 10/30/2006
Publication Date: 12/24/2006
Citation: Luo, M., Liu, J., Lee, D., Guo, B. 2006. A microarray-based analysis of gene expression profiles of maize kernel during late development stages [abstract]. In: Proceedings of the Plant and Animal Genome XV Conference, January 13-17, 2007, San Diego, CA. p. 745. Interpretive Summary:
Technical Abstract: Maize oligonuleotide array was used to analyze the temporal patterns of gene expression in maize kernels during late developmental stages. There is a total of 57,452 70-mer oligonucleotides on the array. In this study, we analyzed gene expression profiles in the process of kernel development of inbred Tex6, which was reported with reduced aflatoxin contamination. We compared the transcriptional profiles of developing kernels at 25, 30, 35, 40, and 45 DAP (day after pollination). There was a total of 8621 positive array spots with unique sequence IDs and 4247 cross-talking genes identified in all sampling stages. These were averaged at 6218 array spots expressed in each sampling stage. Expression patterns of the key genes in several metabolic pathways including starch and lipid metabolisms as well as storage proteins were analyzed. Among the storage proteins, defense related genes of 2676 unique sequence IDs were selected for further comparison. The expression trends of these selected genes were identified as up-regulated, down-regulated, or no-change based on hierarchical analysis. Some defense related genes were found to be expressed extensively through the later kernel development. Twenty genes with different expression trends from microarray analysis were chosen for validation using quantitative real-time PCR. The real-time PCR data reproduced the expression trends of up- and down-regulated genes of microarray data, but did not completely reproduce the microarray data of genes without change in microarray expression analysis. Gene ontology annotation provided a global overview of the molecular biological function of these genes differentially expressed during maize kernels at the later development stages. This study investigated the gene categories at various stages of kernel development, therefore providing further insights into the molecular importance of the gene expression associated with the reduction of aflatoxin contamination in maize line Tex6.