Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download RGC8-S3O01_C. Dardick
Document related concepts
no text concepts found
Transcript
DECIPHERING THE MOLECULAR AND GENETIC CONTROL OF TREE ARCHITECTURE Chris Dardick Appalachian Fruit Research Station USDA Agricultural Research Service GREEN REVOLUTION FOR THE 21ST CENTURY Conventional Rice GR Rice Khush (2001) Nature Genetics Super Rice (21st Century) ? Conventional Fruit Tree Super Tree (21st century) ? Managing fruit/nut trees • Pruning • Training • Trellising • Dwarfing rootstocks • Chemical sprays • Flower/fruit thinning • Harvesting • Land/water use Labor is the major cost! Genetic Optimization of Tree Shape? Structural parameters: • Plant size • Branch outgrowth • Branch length • Branch orientation • Tensile strength *There is a growing body of literature on these aspects of plant development. Still, many key questions remain. Exploiting natural variations in tree shape Brachytic dwarf standard Compact pillar weeping Tree Architecture • Branch orientation • Branching pattern • Tree size PILLAR GROWTH IN PEACH • Pillar also called columnar or broomy • Codominant inheritance – br gene • Caused by mutation of the PpeTAC1 gene. (Dardick et al., 2013) Standard (BrBr) Upright (Brbr) Pillar (brbr) TAC1 influences tiller and leaf angle in rice and corn. TAC1 genes are part of a larger, poorly conserved gene family, dubbed IGT. EAR-like motif on C-terminus. The IGT Gene Family LAZY1 DRO1 TAC1 TAC1 is required for outward branch orientation in dicots Col tac1/tac1 control TAC1:RNAi LAZY1 is also an IGT family gene and functions opposite of TAC1 via altered gravitropism in rice and maize Yoshihara et al. 2007 Maize standard lazy1 Howard (2014) PLOSone Model for gravity signaling in rice shoots LAZY1 is required for upward branch orientation in dicots Col-0 lazy1 control LAZY1 RNAi Is there a genetic relationship between TAC1 and LAZY1? WT tac 1 lazy1 tac1;lazy1 * lazy1 is ‘epistatic’ to tac1 Hollender et al., Unpublished How do tac1 and lazy1 functions intersect with environmental responses? Gravitropic Response of tac1 and lazy1 plants. Rate of gravitropic bending. 6hrs 24hrs 90000 wild type (col) tac1 lazy1 Area of Best Fitting Circle 30min col 80000 tac lazy 70000 60000 50000 40000 30000 20000 10000 0 0 2 4 6 8 Time (hours) 10 Hollender et al., Unpublished 12 TAC1 expression (but not LAZY1) is light dependent Arabidopsis 160 80 0 Peach Relative Expression 2hr 140 70 0 0hr 10min 1hr 6hr 24hr 48hr 72hr RNA-seq Global Gene Expression Analysis Next gen sequencing Upright Orientation wt tac1 lazy1 After Gravistimulation 15 min 45 min 120 min Standard (BrBr) Pillar (brbr) Gene Expression Analysis Differential Expression of: • Cell wall and defense-related genes (peach and Arabidopsis) • Auxin transport and signaling genes in Arabidopsis lazy1 • Entire glucosinolate biosynthetic pathway in Arabidopsis • Auxin precursors • Up in tac1 mutants, down in lazy1 TAC1 and LAZY1 Integrate Light and Gravity Signals to Set Branch Orientation Ongoing and Future Work Automated 3D imaging for Precision Phenotyping of Tree Architecture (photos courtesy of Amy Tabb) Standard TAC1 RNAi LAZY1 RNAi ACKNOWLEDGEMENTS Collaborators Funding Co-PDs Ann Callahan Ralph Scorza Tom Tworkoski Amy tabb Kenong Xu Postdocs/Graduate Courtney Hollender Jessica Guseman Karina Ruiz-Carrasco Undergraduate Students Bert Abbott Tetyana Zhebentyayeva Michael Whitaker Emma Acly Courtney Knill Technicians Elizabeth Lutton Mark Demuth Linda Dunn Renate Horn This work was supported by the Agriculture and Food Research Initiative competitive grant #2012-67013-19395 from the USDA National Institute of Food and Agriculture and by the National Science Foundation Plant Genome Research Program #1339211.
Related documents