Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/15/2004
Publication Date: 9/15/2004
Citation: Chen, G.Q., He, X., Liao, L., McKeon, T.A. 2004. 2s Albumin Gene Expression in Castor Plant (Ricinus communis L.). Journal of the American Oil Chemists' Society. 81(9):867-872. Interpretive Summary: Castor seed 2S albumins are highly allergenic proteins and are detrimental to reintroduction of castor as crop. As part of a genetic approach to eliminate 2S albumin from castor, we investigated the developmental expression of this gene in castor seed.
Technical Abstract: In the castor plant (Ricinus communis L.), 2S albumins are highly allergenic seed proteins and are detrimental to reintroduction of castor as crop. Others have previously shown that the two 2S albumins are encoded by a single gene and processed from a precursor protein in castor. Little is known about the expression pattern of the 2S albumin gene. As part of a genetic approach to eliminate 2S albumin from castor, we investigated the developmental expression of this gene in castor seed. In order to assess seed developmental age quickly and accurately, we established a set of simple criteria, which includes two visual markers, seed coat color and endosperm volume, and defined three phases that encompass the course of castor seed development. Northern analysis indicated that the 2S albumin mRNA is highly abundant in the mid-phase of seed development. A comparison of 2S albumin genomic DNA and cDNA clones from two castor cultivars indicates that there is only a single gene expressed. Protein domain sequence analysis revealed that castor 2S albumin contains the trypsin/alpha-amylase inhibitor family domain, suggesting a role for the albumin in insect resistances.