Immunoblotting Analysis of nsLTP1 in Cereal Grains with Antiserum Raised against Recombinant Rice nsLTP1

Nonspecific lipid transfer protein 1 (nsLTP1) is widely distributed in plants and has been recognized as a widely cross-reacting plant pan-allergen. In the present study, a recombinant protein of rice nsLTP1 was prepared with an Escherichia coli expression system, and polyclonal antiserum was raised by immunizing rabbits with this recombinant nsLTP1. The antiserum specifically immunoreacted with rice nsLTP1 and homologous nsLTP11 proteins of other kinds of cereal grains. Moreover, the antiserum was applied to compare nsLTP1 content among rice cultivars and among rice fractions separated by grain-milling. Variation of nsLTP1 contents were observed among rice cultivars, and rice nsLTP1 was proved to be mainly located in the outer layer of rice grains, providing evidence for decreasing nsLTP1 content by grain-milling.