Team:Nevada/Project/

iRICE: A Novel, Non-GM Approach to Biofortification of Rice
Even though white rice is a major source of calories for over half the world’s population, it is a poor source of nutrients. While rice can be fortified using vitamin powders, such approaches have had limited success because many vitamins are leeched away during the washing process prior to cooking. To address this problem, we have engineered proteins that will adhere nutrients to rice grains and prevent losses. These proteins contain a starch-binding domain that is fused to specific nutrient-binding domains. Because rice is composed mainly of starch, the starch-binding domain prevents nutrient leeching during washing. Upon cooking, the nutrient-binding domain denatures and releases the nutrients into the cooked rice. Supplementing rice with these fusion proteins will provide a novel, non-GMO approach to fortifying rice. Proteins with a starch-binding domain connected to a Vitamin b12-binding domain, a thiamine-binding domain, a lysine-rich protein, and a RFP have been created.

The Problem with Rice

The Old GMO Approach to Fortification

The iRICE System

Starch-binding Protein

Customizable Constructs

The idea behind this project was to create a complex that is not only effective in nutrient enhancement but adaptable to the specific needs of various populations. The costruct consists of a starch binding protein that will adhere to (in this case) the starch in rice, and one of any number of binding proteins. This is where the customization comes in. The combinations or binding proteins you can use is diverse. In our case we have used Thiamine and Cobalamin binding proteins that will adhere available vitamins from the environment, but one could use any number of vitamin, amino acid, or pharamaceutical (speculatively) binding proteins.

Possiblility of GM utilization

Given the current opinion towards GMOs we have designed our constructs to be used as an additive that could be used in a coating or dusting process. However, the potential for GMO exists should popular opinion change in the future. Rather than create supplimental proteins that must be added in the milling process the vitamin binding proteins would be expressed by the plants themselves.

Vitamin B12 Binding Protein

Thiamine Binding Protein

Lysine Rich Protein

Our Results

Proof of Concept

Red Fluorescent Protein

Red Fluorescent Protein is a protein that glows red when exposed to visible light. RFP and other fluorescent proteins are used frequently in biological experiments as marker proteins.

Results

RFP was combined with Starch binding protein successfully. The construct was used to show that the starch binding protein can bind to rice. After binding, we also used an amylase column to show binding.

Conclusions for project

Each of the proteins was expressed successfully with a starch binding domain and their nutrient binding components shown to bind their nutrient. The red fluorescent protein shows the functionality of the starch binding protein. With both domains shown to be working, our project comes to a successful close.

References