Department of Plant, Soil and Environmental Sciences, University of Florence, Florence, Italy.
Plant Cell Physiol. 2011 Jun;52(6):1107-16. doi: 10.1093/pcp/pcr061. Epub 2011 May 6.
The effect of a hypoxic pre-treatment (HPT) on improving tolerance to prolonged anoxia conditions in two contrasting Vitis species (V. riparia, anoxia tolerant; V. rupestris, anoxia sensitive) was evaluated. The energy economy of root cells was studied by measuring heat production, the activity of pyruvate decarboxylase (PDC) and alcohol dehdrogenase (ADH), ethanol and ATP production, and K(+) fluxes. The results showed that HPT is an effective tool in order to maintain a sustainable metabolic performance in both the species under anoxia conditions, especially in sensitive species such as V. rupestris. Our results showed that the improved tolerance was mainly driven by: (i) an enhanced activity of key enzymes in alcohol fermentation (ADC and PDC); (ii) the capability to maintain a higher level of respiration, evidenced by a lesser decrease in heat development and ATP production; and (iii) the maintenance of a better ion homeostasis (highlighted by measurement of K(+) fluxes) and K(+) channel functionality.
本研究评估了低氧预处理（HPT）对提高两种葡萄属植物（耐缺氧的 V. riparia 和缺氧敏感的 V. rupestris）耐受长时间缺氧条件能力的影响。通过测量产热量、丙酮酸脱羧酶（PDC）和醇脱氢酶（ADH）活性、乙醇和 ATP 产生以及 K(+)通量来研究根细胞的能量代谢。结果表明，HPT 是在缺氧条件下维持两种植物可持续代谢性能的有效工具，特别是在 V. rupestris 等敏感物种中。我们的结果表明，耐受性的提高主要归因于：（i）增强了酒精发酵中的关键酶（ADC 和 PDC）的活性；（ii）维持更高水平呼吸的能力，表现在产热量和 ATP 产生的减少较少；以及（iii）维持更好的离子稳态（通过测量 K(+)通量来突出）和 K(+)通道功能。
