Evidence against the occurrence of adenosine-3′:5′-cyclic monophosphate in higher plants

摘要

Previous reports on the incorporation of 14Cadenine into adenosine-3′:5′-cyclic monophosphate (cyclic AMP) in oat (Avena sativaL.) and maize (Zea maysL.) coleoptile sections, chick-pea (Cicer arietinumL.) embryos and barley (Hordeum vulgareL.) aleurone layers were reexamined. Separation of labelled nucleotides on DEAE-Sephadex A 25 showed that a peak of14C activity, previously considered to be cyclic AMP, is not identical with this compound. Attempts to detect the cyclic nucleotide by means of a highly specific protein-kinase assay in various plant tissues (Nicotiana tabacumL., tissue culture;Catharanthus roseusDon., tissue culture;Lycopersicon esculentumMill, seedlings;Nicotiana tabacum, pith parenchyma;Avena sativa, coleoptiles) failed even though up to 100 g of plant material was extracted and a number of control experiments were carried out to insure that cyclic AMP, if present in the extracts, could be measu