Project description:We have employed whole genome microarray expression profiling as a discovery platform to identify genes to alter the transcript accumulation levels in a grass-clump dwarf line, which is a synthetic hexaploid line from triploid hybrids crossed between tetraploid wheat (Triticum turgidum ssp. durum cv. Langdon) and a diploid wheat relative Aegilops umbellulata (KU-4052). Up-regulation of metabolic and catabolic processes-related genes for cell wall-associated molecules was observed, and down-regulation of wheat APETALA1-like MADS-box genes, considered to act as flowering promoters, was found in the grass-clump dwarf line. Unusual expression of the branching-related SPLs and flowering time regulation-related MADS-box genes could explain the grass-clump dwarf phenotype.
Project description:We have employed whole genome microarray expression profiling as a discovery platform to identify genes to alter the transcript accumulation levels in SGA plants, which are triploid hybrids crossed between tetraploid wheat and a diploid wheat relative Aegilops umbellulata. Of the up-regulated genes, cell death and carboxy-lyase activity-related genes were the most frequently found in crown tissues of SGA plants. On the other hand, photosynthesis-related genes were highly down-regulated in crown tissues of SGA plants. In addition, transcript accumulation levels of shoot apical meristem (SGA)-related genes such as knotted-1 like homeobox (Knox) genes were also repressed in SGA plants. The microarray analysis strongly suggests that an autoimmune response-like reaction might be triggered by intergenomic incompatibility between the AB and U genomes in SGA. In addition, SAM-related and cell cycle-related genes were dramatically down-regulated in crown tissues of SGA, indicating that abnormalities of SAM are associated with the abnormal growth phenotypes in SGA.
