Rapid Changes in Protein Phosphorylation Associated with Light-Induced Gravity Perception In Corn Roots

Abstract
The effect of light and calcium depletion on in vivo protein phosphorylation was tested using dark-grown roots of Merit corn. Light caused rapid and specific promotion of phosphorylation of three polypeptides. Pretreatment of roots with ethylene glycol bis N,N,N'',N'' tetraacetic acid and A23187 prevented light-induced changes in protein phosphorylation. We postulate that these changes in protein phosphorylation are involved in the light-induced gravity response.