Devaiah Shivakumar P, Pan Xiangqing, Hong Yueyun, Roth Mary, Welti Ruth, Wang Xuemin
Department of Biology, University of Missouri, St Louis, MO 63121, USA.
Plant J. 2007 Jun;50(6):950-7. doi: 10.1111/j.1365-313X.2007.03103.x.
Seed aging decreases the quality of seed and grain and results in agricultural and economic losses. Alterations that impair cellular structures and metabolism are implicated in seed deterioration, but the molecular and biochemical bases for seed aging are not well understood. Ablation of the gene for a membrane lipid-hydrolyzing phospholipase D (PLDalpha1) in Arabidopsis enhanced seed germination and oil stability after storage or exposure of seeds to adverse conditions. The PLDalpha1-deficient seeds exhibited a smaller loss of unsaturated fatty acids and lower accumulation of lipid peroxides than did wild-type seeds. However, PLDalpha1-knockdown seeds were more tolerant of aging than were PLDalpha1-knockout seeds. The results demonstrate the PLDalpha1 plays an important role in seed deterioration and aging in Arabidopsis. A high level of PLDalpha1 is detrimental to seed quality, and attenuation of PLDalpha1 expression has the potential to improve oil stability, seed quality and seed longevity.
种子老化会降低种子和谷物的质量，并导致农业和经济损失。损害细胞结构和新陈代谢的变化与种子劣变有关，但种子老化的分子和生化基础尚未得到充分了解。拟南芥中一种膜脂水解磷脂酶D（PLDα1）基因的缺失增强了种子在储存或暴露于不利条件后的萌发和油脂稳定性。与野生型种子相比，PLDα1缺陷型种子的不饱和脂肪酸损失较小，脂质过氧化物积累较低。然而，PLDα1基因敲低的种子比PLDα1基因敲除的种子更耐老化。结果表明，PLDα1在拟南芥种子劣变和老化中起重要作用。高水平的PLDα1对种子质量有害，降低PLDα1的表达水平有可能提高油脂稳定性、种子质量和种子寿命。
