Occurrence of prenylated proteins in plant cells.

In this paper evidence is presented for the occurrence of prenylated proteins in plants. When spinach leaves were incubated in the presence of [3H]mevalonate non-extractable lipids were found in the protein fraction after extraction with organic solvents. Alkaline hydrolysis liberated phytol, polyprenyl phosphates-11-15 and also, in contrast to animal cells, polyprenols-11-15. Complete removal of farnesol and geranylgeraniol required the cleavage of thioether linkages by iodomethane. The results indicate that several polyisoprenoid lipids in plant cells are covalently bound to proteins. So far a protein fraction dominated by one or more proteins in the 23 kDa region has been identified.