Location: Plant Gene Expression Center2010 Annual Report
1a. Objectives (from AD-416)
Determine the molecular mechanisms by which plants perceive and respond to developmental, biotic and abiotic signals throughout the life cycle to enhance the quality and production efficiency of agriculturally important crops.
1b. Approach (from AD-416)
A combination of modern molecular, genetic, genomic, proteomic and bioinformatic approaches will be used to address this multifaceted problem. Particular emphasis will be placed on identifying signaling components, regulatory genes and transcriptional networks involved in controlling plant responses to developmental, biotic and abiotic signals. Genes that respond to light under control of the phytochrome photosensory system will be identified and the regulatory mechanisms defined. Genes involved in regulating the circadian clock will be identified and functionally defined. Genes controlling vegetative and reproductive development will be identified and characterized. Plant hormone function in mediating growth and developmental responses will be explored. Genes involved in plant responses to biotic and abiotic challenges will be identified and characterized. On an ongoing basis, cutting-edge strategies and technologies in areas such as targeted reverse-genetic gene disruption, high-density microarray analysis, and biocomputational approaches, will be assimilated and will be identified and characterized. Formerly 5335-21000-027-03S (1/10). Documents SCA with UC Berkeley.
3. Progress Report
This is a new project that replaced 5335-21000-027-03-S which is continuing and expanding upon the work of the former projects 5335-21430-007-00D, 5335-22000-007-00D, and 5335-21000-026, -027, -028, -027, -029, -030 and -031-00D ARS scientist demonstrated that the BOP1 and BOP2 regulatory proteins control leaf formation by suppressing KNOX1 and YABBY transcription factor activity at the base of the organ. Results were reported in the peer-reviewed journal Genes & Development (Ron, M. et al. 2010. Genes & Dev 24: 1010-1021). ARS scientist identified a maize mutant with increased glucan in the cell wall, an impediment to plant feedstocks and identified the tasselsheath4 gene that regulates leaf size which is critical for improving biofeedstocks. Research results were published in six publications. ARS scientist demonstrated that mutants without normal circadian rhythms could not distinguish between moderate and warm temperatures and that maize genes with expression regulated by the circadian clock is integral to maize photosynthesis, carbohydrate metabolism, cell wall synthesis, and phytohormone production. Research results published in Genome sequencing and analysis of the model grass Brachypodium distachyon. Nature. 463:763-768. Demonstrated that ARS scientist analyzed plants regenerated from calluses and showed that site specific integration mediated by the Bxb1 recombination system occurred at a ~10% frequency. This is practical for commercial developers to obtain site-specifically integrated transgenes, and will help speed the development of more precisely engineered transgenic varieties. Research results were published in The phiC31 Recombinase Demonstrates Heritable Passage of Site-specific Genomic Excision in Arabidopsis. BioMed Central (BMC)Biotechnology.Available:doi:10.1186/1472-6750-10-17. An ARS scientist concluding 10 years of research on the function of the ACC synthase enzymes encoded by 9 genes in Arabidopsis. The results revealed a critical role for ACC and were published in A Combinatorial Interplay Among the 1-Aminocyclopropane-1-carboxylate Isoforms Regulates Ethylene Biosynthesis in Arabidopsis thaliana. Genetics. doi:10.1534/genetics.109.107102 An ARS scientist investigated the functional and evolutionary properties of three pathogen disease resistance loci of wild Solanum species using comparative genomics. Results were published Identification of miniature inverted-repeat transposable elements (MITEs) and biogenesis of their siRNAs in the Solanaceae: New functional implications for MITEs. Genome Research. 19:42-56 and Inferred origin of several Native American potatoes from the Pacific Northwest using SSR markers. Euphytica. 174:15-29. Research at the PGEC provides an essential knowledge base for biotechnology's impact on agriculture. The knowledge has moved from determining the function of single genes to elucidation of entire networks. This information can be used to understand the function of developmental processes in crop processes. Monitoring of activities is carried out by weekly seminars and monthly meetings.