Nevada Dividends!

Engineering Plants For Increased Nutrition And Increased Stress Tolerance


Issue:

Thiamin (Vitamin B1) is an essential plant derived nutrient in human and animal diets. While not limiting in typical Western diets, thiamin deficiencies are common in developing countries where people subsist on diets consisting primarily of polished grains and seed products. By increasing thiamin levels in the seeds of important subsistence crop species such as rice and wheat, we can make a positive impact on human nutrition and global food security.

What has been done?

Using standard molecular biology techniques, the open reading frames corresponding to the Arabidopsis enzymes (HET-P synthase, HMP-PP synthase and TMPPase), complementary DNA sequences were sub-cloned behind the rapeseed’s napin and oleosin promoters, and the soybean glycinin promoter, respectively. Mature seed from each line were analyzed for seed thiamin content using reverse phase HPLC. The team obtained a cDNA clone corresponding to the sesame seed thiamin binding protein and created constructs that were transferred into first Arabidopsis and then into Camelina. To assess stress tolerance in the transgenic plants with elevated seed thiamin, the team used the highly sensitive root growth assay developed for Arabidopsis in an earlier NAES HATCH project.

Impact:

This year significant progress has been made in engineering thiamine production in the model plant Arabidopsis. The team engineered Arabidopsis seed with 8+ fold increase in seed thiamine continent. Improved seed mass of thiamine enriched plants by 25% over wild types, increased seed oil continent by 10%, increased carbohydrates by 30%, and proved to be more tolerant to paraquate and salt induced oxidative stress. Finally, the team has genetically engineered False Flax (Camelina sativa) with three thiamine biosynthetic genes cloned behind seed specific promoters.

CONTACT INFORMATION

David Shintani

Department of Biochemistry and Molecular Biology

1664 North Virginia Street

Reno, Nevada   89557

 

Phone: (775) 784-1740

Email: shintani@unr.edu

Personal Web Site: