Changes in Soluble Sugars and Proteins during Development of Rye Coleoptiles

Abstract

Summary An analysis was made of the changes in dry mass, soluble sugars and protein complement in coleoptiles of rye seedlings ( Secale cereale L.) that were either grown in darkness or irradiated with white light. Dry mass and the concentration of soluble sugars (glucose, fructose) increased during growth of the juvenile organ. After emergence of the primary leaf (cessation of coleoptile elongation) dry mass and sugar content decreased. Cytoplasmic proteins have been extracted from growing and non-growing (mature) coleoptiles and separated by gel electrophoresis. Examination of the silver stained profiles of polypeptides revealed only minor chnages, i.e. no loss of protein was detected. Because protein breakdown is a main characteristic of senescence, we conclude that the pierced coleoptile is a mature, metabolically active organ that provides carbohydrates for the growing parts of the developing seedling.