环境胁迫和激素诱导甘蔗ACC合成酶基因家族三个成员的表达

Expression of Three Members of ACC Synthase Gene Family in Sugarcane Induced by Hormones and Environmental Stress

ACC合成酶(ACS)是高等植物乙烯生物合成途径中的限速酶。在克隆到甘蔗ACC合成酶基因家族3个成员Sc-ACS1、Sc-ACS2和Sc-ACS3的基础上,分别以它们作为探针,检测了激素诱导和环境胁迫对甘蔗苗期该3成员表达的影响。结果表明,乙烯利诱导Sc-ACS1在叶中表达,在根中不表达;Sc-ACS2在根、叶中表达;Sc-ACS3主要在根部表达,在叶中不表达。在甘蔗叶片中,Sc-ACS1对冷胁迫、暗培养和LiCl胁迫均有应答,并受植物生长激素IAA诱导而表达;Sc-ACS2无论是在生长激素诱导还是环境胁迫下,其mRNA均维持较低水平。

1-aminocyclopropane-1-carboxylic acid synthase is one of the key rate-limiting enzymes for ethylene biosynthesis in higher plants. Based on the cloning of Sc-ACS1, Sc-ACS2 and Sc-ACS3 of ACS gene families, their expressions were tested in the roots and leaves of sugarcane with Sc-ACS1, Sc-ACS2 and Sc-ACS3 as the probes, respectively. The results of Northern blotting analysis showed that the expression of Sc-ACS1 was induced by ethephon in leaves, but not in roots; that of Sc-ACS2 in leaves and roots; and that of Sc-ACS3 in roots, while not in leaves. Under the environmental stresses （cold stress, dark-growing condition and LiCl stress）and hormone inducement （IAA）, the mRNA of Sc-ACS1 showed a higher expression while that of Sc-ACS2 maintained low expression level in leaves.