The Effect of Ultracentrifugation on Fine Structure and α-Amylase Production in Barley Aleurone Cells

Ultracentrifugation of barley aleurone cells results in the stratification of organelles thus allowing for a quantitation of those organelles. Gibberellic acid (GA(3))-stimulated alpha-amylase production in stratified cells is reduced by centrifugation at gravitational forces greater than 40,000g. Forces below 30,000g do not affect GA(3)-stimulated alpha-amylase production although stratification of organelles occurs at these forces. The ability of centrifuged cells to respond maximally to GA(3) by producing alpha-amylase is related to the degree of redistribution of organelles within these cells. Thus, recovery of cells from centrifugation at forces below 30,000g is rapid, while recovery from forces above 40,000g is slow.