CAJ | 학술논문

以大豆幼苗初生叶为材料研究了衰老过程中质膜蛋白激酶自磷酸化状态和催化活性的变化。结果发现质膜上一个57kD的蛋白激酶分子上有多个自磷酸化位点，而且自磷酸化反应能提高该酶催化组蛋白H1磷酸化的激酶活力。进一步的研究表明诱导衰老处理造成的57kD蛋白激酶自磷酸化状态的变化，可能对调节它在衰老过程中催化活性的变化起重要作用；而外源6-BA预处理则能够维持57kD蛋白激酶体内高自磷酸化状态，保持该激酶在衰老过程中的催化活力。对衰老和6-BA处理过程中质膜上39和47kD蛋白激酶自磷酸化状态变化的研究表明，这两种激酶可能参与大豆叶片对6-BA刺激信号的传导和/或应答反应过程。
이대두유묘초생협위재료연구료쇠로과정중질막단백격매자린산화상태화최화활성적변화。결과발현질막상일개57kD적단백격매분자상유다개자린산화위점，이차자린산화반응능제고해매최화조단백H1린산화적격매활력。진일보적연구표명유도쇠로처리조성적57kD단백격매자린산화상태적변화，가능대조절타재쇠로과정중최화활성적변화기중요작용；이외원6-BA예처리칙능구유지57kD단백격매체내고자린산화상태，보지해격매재쇠로과정중적최화활력。대쇠로화6-BA처리과정중질막상39화47kD단백격매자린산화상태변화적연구표명，저량충격매가능삼여대두협편대6-BA자격신호적전도화/혹응답반응과정。
Here we report an experimental system in volving soybean primaryleaves which are highly sensi tive to senescence-inducing treatment (ST) and exog enous 6-BA application for the study of the mechanism of the retardation of leaf senescence. By using a modified method suggested by Ferrell and Martin (1991)for detecting autophosphorylation activity of protein kinases, as well as by using a protocol of in vitro rephosphorylation of the samples with unlabelled ATP,we studied the possible effect of autophosphorylation on catalytic activity of protein kinases associated with plasma membrane of soybean primary leaves. The results suggested that there were multiple sites on a 57kD calcium-dependent protein kinase (CDPK) molecule for utophosphorylation and that autophosphorylation could improve its catalytic activity in phosphorylating histone H1. ST-induced changes in in vivo autophosphorylation status of the 57 kD CDPK may play an important role in regulating its catalytic activity during leaf senescence, and 6-BA pretreatment may make the high catalytic activity of this kinase longlasting. The effect of 6-BA application on ST-induced changes of utophosphorylation activity of a 39 kD and a 47 kD protein kinases implied involvement of these two kina ses in cytokinin stimulus/response cascade system.