Protein Synthesis in the Desiccation Tolerant AngiospermXerophyta villosaduring Dehydration

Abstract

Leaves of the resurrection plant Xerophyta villosa appear to become desiccation tolerant while they dry on the intact plant. After a small decline during moderate water stress, the polyribosome content of attached leaves appears to rise at 50% relative water content (RWC) to almost double the content in controls, before it finally declines to zero at 20% RWC. Partition of leaf soluble protein by polyacrylamide gel electrophoresis indicates an increase in protein with low mobility in dehydrated leaves. Studies on the incorporation of ¹⁴C-valine and ³H-valine, and of proteins dissociated into their component polypeptddes suggest that protein synthesis during dehydration is at least partly responsible for the changes in soluble protein.