Changes in non-histone chromosomal proteins during the development of potato tubers; their involvement in wound- and hormone-induced processes

摘要

The electrophoretic pattern of non-histone chromosomal proteins (NHC proteins) changes specifically during the formation, dormancy and sprouting of white potato tubers (Solanum tuberosumL.). With increasing age some NHC proteins evidently become eliminated. Consequently the electrophoretic pattern of these proteins is strictly dependent on the developmental stage of the organ.Wounding and treatment of wounded tissues with 10−7Mgibberellic acid (GA3) drastically influence the pattern of NHC proteins in potato tuber tissues. Although actively growing organs respond to injury by increased synthesis of the NHC proteins already present in the intact tuber, older tubers react with the formation of new NHC proteins. By contrast, sprouts loose many NHC proteins, if wounded or wounded and concomitantly treated with GA3. Wounding and treatment of wounded tuber parenchyma with GA3both induce qualitative changes in NHC proteins: these proteins become highly active in restoring the histone-inhibited transcription of DNA in vitro, whereas in the intact resting tuber they are virtually inactive. Our present results support the hypothesis that hormones govern the quality of NHC proteins of a given tissue and through this the quality of transcriptio