Department of Biological Science, Sungkyunkwan University, Suwon, Gyeong-gi 440-746, Korea.
Plant Physiol. 2012 Apr;158(4):1955-64. doi: 10.1104/pp.111.189829. Epub 2012 Jan 9.
Sucrose-nonfermentation1-related protein kinase1 (SnRK1) is an evolutionarily conserved energy sensor protein that regulates gene expression in response to energy depletion in plants. Efforts to elucidate the functions and mechanisms of this protein kinase are hampered, however, by inherent growth defects of snrk1-null mutant plants. To overcome these limitations and study SnRK1 functions in vivo, we applied a method combining transient expression in leaf mesophyll protoplasts and stable expression in transgenic plants. We found that both rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana) SnRK1 activities critically influence stress-inducible gene expression and the induction of stress tolerance. Genetic, molecular, and chromatin immunoprecipitation analyses further revealed that the nuclear SnRK1 modulated target gene transcription in a submergence-dependent manner. From early seedling development through late senescence, SnRK1 activities appeared to modulate developmental processes in the plants. Our findings offer insight into the regulatory functions of plant SnRK1 in stress-responsive gene regulation and in plant growth and development throughout the life cycle.
蔗糖非发酵 1 相关蛋白激酶 1（SnRK1）是一种进化上保守的能量传感器蛋白，可调节植物中因能量耗竭而导致的基因表达。然而，由于 snrk1 缺失突变体植物固有的生长缺陷，阐明这种蛋白激酶的功能和机制的努力受到了阻碍。为了克服这些限制并在体内研究 SnRK1 功能，我们应用了一种结合叶肉原生质体瞬时表达和转基因植物稳定表达的方法。我们发现，水稻（Oryza sativa）和拟南芥（Arabidopsis thaliana）的 SnRK1 活性都严重影响胁迫诱导基因表达和胁迫耐受性的诱导。遗传、分子和染色质免疫沉淀分析进一步表明，核 SnRK1 以依赖淹水的方式调节靶基因转录。从早期幼苗发育到后期衰老，SnRK1 活性似乎调节植物的发育过程。我们的研究结果为植物 SnRK1 在胁迫响应基因调控以及植物生长发育整个生命周期中的作用提供了新的认识。
