Christianson Jed A, Wilson Iain W, Llewellyn Danny J, Dennis Elizabeth S
CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia.
Plant Physiol. 2009 Apr;149(4):1724-38. doi: 10.1104/pp.108.131912. Epub 2009 Jan 28.
Low-oxygen stress imposed by field waterlogging is a serious impediment to plant germination and growth. Plants respond to waterlogging with a complex set of physiological responses regulated at the transcriptional, cellular, and tissue levels. The Arabidopsis (Arabidopsis thaliana) NAC domain-containing gene ANAC102 was shown to be induced under 0.1% oxygen within 30 min in both roots and shoots as well as in 0.1% oxygen-treated germinating seeds. Overexpression of ANAC102 altered the expression of a number of genes, including many previously identified as being low-oxygen responsive. Decreasing ANAC102 expression had no effect on global gene transcription in plants but did alter expression patterns in low-oxygen-stressed seeds. Increasing or decreasing the expression of ANAC102 did not affect adult plant survival of low-oxygen stress. Decreased ANAC102 expression significantly decreased germination efficiency following a 0.1% oxygen treatment, but increased expression had no effect on germination. This protective role during germination appeared to be specific to low-oxygen stress, implicating ANAC102 as an important regulator of seed germination under flooding.
田间渍水造成的低氧胁迫是植物萌发和生长的严重障碍。植物通过一系列在转录、细胞和组织水平上调控的复杂生理反应来应对渍水。拟南芥中含NAC结构域的基因ANAC102在根和地上部分以及经0.1%氧气处理的萌发种子中,于30分钟内在0.1%氧气条件下被诱导表达。ANAC102的过表达改变了许多基因的表达,包括许多先前鉴定为低氧响应的基因。降低ANAC102的表达对植物的整体基因转录没有影响,但确实改变了低氧胁迫种子中的表达模式。增加或降低ANAC102的表达并不影响成年植物在低氧胁迫下的存活。降低ANAC102的表达在0.1%氧气处理后显著降低了萌发效率,但增加表达对萌发没有影响。这种在萌发过程中的保护作用似乎对低氧胁迫具有特异性,这表明ANAC102是淹水条件下种子萌发的重要调节因子。