Zein is a prolamine; an alcohol-soluble protein present
in amounts of 2.5-10% (dry basis) in corn. Zeins are the main storage proteins found in the seeds of maize. Following protein translation, the zeins are stored in the rough endoplasmic reticulum (ER)-derived protein bodies. The accumulation of zein in these ER-derived protein bodies results in the
formation of the endosperm - the food storage body of
seeds. Currently, there are four classes of zein: α, β, γ, and δ.
These classes are expressed sequentially in maize and are found to interact with each other for stability. Zein from corn was reported to be approximately 35% α-zein, which includes 2 prominent bands of 22 and 24 kDa. β-zein fails to enter an SDS-PAGE gel without reduction. Reducing SDS-PAGE analysis shows that β-zein has 3 major bands of 24, 22, and
14 kDa.
