Two Arabidopsis mutants that overproduce ethylene are affected in the posttranscriptional regulation of 1-aminocyclopropane-1-carboxylic acid synthase.
Two Arabidopsis mutants that overproduce ethylene are affected in the posttranscriptional regulation of 1-aminocyclopropane-1-carboxylic acid synthase.
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DOI：
10.1104/pp.119.2.521
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发表时间：
1999-02
期刊：
影响因子：
7.4
通讯作者：
K. Woeste;Chen Ye;J. Kieber
中科院分区：
文献类型：
--
作者：
K. Woeste;Chen Ye;J. Kieber
拟南芥突变体eto 1（乙烯过度生产者）和eto 3作为黄化幼苗产生升高水平的乙烯。乙烯生产在这些幼苗的峰值在60至96小时，然后下降到几乎野生型的水平。乙烯在eto 1和eto 3中的过量产生主要限于黄化幼苗;光生长的幼苗和各种成体组织产生接近野生型乙烯量。通过不同的1-氨基环丙烷-1-羧酸（ACC）合酶（ACS）亚型诱导乙烯在野生型，黄化幼苗生物合成的几种化合物被发现与eto 1和eto 3协同作用，乙烯不敏感的突变etr 1（乙烯抗性），它阻止反馈抑制生物合成。ACS活性，乙烯生物合成的限速步骤，是非常高的eto 1和eto 3突变体幼苗，即使RNA凝胶印迹分析表明，ACS mRNA的稳态水平没有增加，包括一个新的拟南芥ACS基因，被确定。完整幼苗ACC转化为乙烯的测量表明，突变不影响ACC的共轭或ACC氧化酶的活性，乙烯生物合成的最后一步。两者合计，这些数据表明，eto 1和eto 3突变提高乙烯生物合成的影响ACS的转录后调控。
The Arabidopsis mutants eto1 (ethylene overproducer) and eto3 produce elevated levels of ethylene as etiolated seedlings. Ethylene production in these seedlings peaks at 60 to 96 h, and then declines back to almost wild-type levels. Ethylene overproduction in eto1 and eto3 is limited mainly to etiolated seedlings; light-grown seedlings and various adult tissues produce close to wild-type amounts of ethylene. Several compounds that induce ethylene biosynthesis in wild-type, etiolated seedlings through distinct 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) isoforms were found to act synergistically with eto1 and eto3, as did the ethylene-insensitive mutation etr1 (ethylene resistant), which blocks feedback inhibition of biosynthesis. ACS activity, the rate-limiting step of ethylene biosynthesis, was highly elevated in both eto1 and eto3 mutant seedlings, even though RNA gel-blot analysis demonstrated that the steady-state level of ACS mRNA was not increased, including that of a novel Arabidopsis ACS gene that was identified. Measurements of the conversion of ACC to ethylene by intact seedlings indicated that the mutations did not affect conjugation of ACC or the activity of ACC oxidase, the final step of ethylene biosynthesis. Taken together, these data suggest that the eto1 and eto3 mutations elevate ethylene biosynthesis by affecting the posttranscriptional regulation of ACS.