【摘要】 水稻黄化幼苗在萌发生长的3～9天中,苯丙氨酸解氨酶活性不断增强,9天以后酶活性有所下降。幼苗不同组织的PAL活性差别很大,以幼叶的活性最高,依次为根、胚轴、胚芽鞘;胚乳中则无PAL活性。去胚乳和根的离体苗随着自然老化的时间进程,PAL活性逐步下降,以最初4小时下降最为明显。PAL活性降低的原因可能是体内合成了某种大分子“抑制蛋白”。PAL的失活与幼苗去除胚乳有关,推测水稻萌发种子的胚乳中可能存在“抑制蛋白”的调节因子。更多还原

【Abstract】 The activity of PAL in etiolated rice seedling gradually increased for 3—9 days during germination, and then decreased slightly. Large differences were observed in the level of PAL activity in different tissues of rice seedling, the highest activity being in the young leaf, next the root, the plumular axis, and the coleopfile, in decreasing order. No activity had been detected in the endosperm.The interesting point was that during ageing, the activity of PAL decreased gradually in excised seedling from which the endosperm and the root had been removed, the largest decrease occurring during the first 4 hours.The inactivation of PAL in rice seedling was closely related with the removal of the endosperm, the extent of inactivation parallelling the severity of cutting. It was thought that rice endosperm might contain some regulating factors which inactivate the "inhibiting protein" of PAL during germination.更多还原