酸性转化酶基因家族在番茄果实发育及逆境胁迫下的表达分析

Expression Analysis of Acid Invertase Gene Family in the Development of Tomato Fruits and under Adversity Stress

以普通栽培番茄(Lycopersicon esculentum)品种桃太郎为试材,通过半定量RT-PCR方法研究了5个转化酶基因在果实不同发育阶段不同部位的表达,并进一步研究了苗期番茄在亚高温、亚低温、NaCl盐胁迫和渗透胁迫下转化酶基因的表达变化。结果表明:果实膨大期主要受Lin5、Lin6和Lin8表达的调控;绿熟期仅有Lin8在发挥作用,而在果实完熟期Lin6、Lin8和AI2的表达明显。这说明在番茄果实发育的不同时期及果实的不同发育部位都受到酸性转化酶基因家族的不同成员的共同调控。亚适温对AI2的影响最明显,无论是亚低温还是亚高温,均能明显抑制AI2的基因表达;而对细胞壁束缚性的转化酶(Lin5、Lin6、Lin7)的表达影响不明显,对Lin8有明显的抑制作用。Lin5和Lin7在渗透胁迫和盐胁迫下均不表达,Lin6和Lin8的表达受盐胁迫和渗透胁迫的抑制,处理3 d时表达变弱,处理5 d后则完全抑制;AI2对渗透胁迫较敏感,处理3 d其表达完全受抑制,而盐胁迫随处理时间的延长,表达逐渐变弱,直至完全消失。

Five invertases were investigated by semi-quantitative RT-PCR in different developing stages of the fruit, using genotype tomatoes,＂Momotaro＂. The invertase genes expressions of tomato seedling under sub-high temperature, sublow temperature, NaCl salinity stress and osmotic stress were further studied. The resul riod of fruit is affected by the expression of Lin5, Lin6 and Lin8. Only Lin8 expressed Lin8 and AI2 expressed distinctly. The results showed that different members of acid different periods and tissues of tomato fruits development ts suggested that the expanding pein mature green stage, while Lin6, invertase gene family regulated the Suboptimal temperature had significant influence on AI2 Whether sub-low temperature or sub-high temperature, both of them inhibited gene expression siguificantly, however, they have little effect on the expression of the cell wall-binding acid invertase genes （ Lin5, Lin6 and Lin7） and have inhibited effect on Lin8. Lin5 and Lin7 have no expression in osmotic stress and salinity stress ; however, the expressions of Lin6 and Lin8 are inhibited by osmotic stress and salinity stress. The expression was low when treated for three days, and for five days it was totally inhibited. AI2 is sensitive to osmotic stress whose expression is totally inhibited when treated for three days, meanwhile under prolonging the time of the salt stress, the expression is low, then completely disappeared.