ARS | Publication request: INCREASED CALCIUM IN CARROTS BY EXPRESSION OF AND ARABIDOPSIS H+/CA2+ TRANSPORTER

Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 11, 2004
Publication Date: November 1, 2004
Citation: Park, S., Kim, C., Pike, L., Smith, R., and Hirschi, K. 2004. Increased calcium in carrots by expression of an Arabidopsis H+/Ca2+ transporter. Molecular Breeding. 14:275-282.

Interpretive Summary: A diet low in calcium can lead to fragile bones and a condition termed osteoporosis. Here we engineer carrot plants to express high levels of a calcium transporter which confers greater levels of calcium to this agriculturally important crop. This type of technology can be used to increased the calcium content in our diets and may eventually help curb the incidence of osteoporosis.

Technical Abstract: Here we demonstrate that carrots expressing the Arabidopsis H+/Ca2+ transporter CAX1 (Cation Exchanger 1) contained up to 50% more calcium (CA)than plants transformed with control vectors. The CAX1-expressing carrots were fertile, and robust plant growth was seen in the majority of the transgenic plants. CAX1-expressing carrots were crossed to a commercial carrot variety to confirm that the increased Ca accumulation was mediated by CAX1-expression, and the increased Ca content was clearly correlated with the transgene. This study suggests that modulation of ion transporters could be an important means of increasing the Ca content of agriculturally important crops. To our knowledge, this study represents the first attempts to use biotechnology to increase the Ca content of an agriculturally important crop.