Preliminary characterization of wheat, Triticum aestivum , embryo globulins

Abstract

The 7S globulins are a subclass of seed storage proteins characterized by their solubility in saline solution. These proteins are major legume storage reserves, and have been studied extensively; in the cereals, they represent a minor seed protein fraction and have been characterized to a lesser extent. Recently, a study associating a wheat 7S globulin, WP5212, with the development of type 1 diabetes in diabetes-prone rats, has renewed interest in this protein class. The present study aimed to better characterize the 7S globulins of wheat. The majority of the wheat embryo globulins were detected by anti-WP5212 polyclonal serum. These proteins varied significantly in their molecular masses and isoelectric points. Six major polypeptides were identified by mass spectrometry and/or N-terminal sequencing as belonging to the globulin 1 family. These results combined with prior studies have allowed the construction of a hypothetical model of the post-translational events contributing to the wheat 7S globulin profile in mature kernels.