Evidence for programmed cell death and activation of specific caspase-like enzymes in the tomato fruit heat stress response
Evidence for programmed cell death and activation of specific caspase-like enzymes in the tomato fruit heat stress response
复制标题
番茄果实热应激反应中程序性细胞死亡和特定半胱天冬酶样酶激活的证据
DOI：
10.1007/s00425-009-0908-4
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发表时间：
2009-05-01
期刊：
影响因子：
4.3
通讯作者：
Luo, Yun-Bo
中科院分区：
文献类型：
--
作者：
Qu, Gui-Qin;Liu, Xiang;Luo, Yun-Bo
番茄（Lycopersicon esculentum）果实是研究肉质果实胁迫反应的最佳模型。细胞程序性死亡（PCD）在哺乳动物和植物的逆境应答中起着重要作用。在这项研究中，我们提供的证据表明，PCD触发番茄果实热应激反应的检测顺序诊断PCD事件，包括释放的细胞色素，激活半胱天冬酶样蛋白酶和TUNEL阳性细胞核的存在。热处理后12小时调查这些事件的时间过程表明，细胞色素释放和半胱天冬酶样蛋白酶激活迅速发生，并与DNA片段化的发病一致。此外，LEHDase和DEVDase酶在热处理和恢复期间在番茄果皮中特异性地被激活。YVAD酶或IETDase蛋白酶无显著活化。预孵育的果皮光盘与广谱，细胞渗透性半胱天冬酶抑制剂Z-VAD-FMK，抑制热诱导的细胞死亡的台盼蓝测量，伴随着LEHDase和DEVDase活动的减少。
The tomato (Lycopersicon esculentum) fruit is the best available model to study the stress response of fleshy fruit. Programmed cell death (PCD) plays an important role in stress responses in mammals and plants. In this study, we provide evidence that PCD is triggered in the tomato fruit heat stress response by detection of the sequential diagnostic PCD events, including release of cytochromec, activation of caspase-like proteases and the presence of TUNEL-positive nuclei. Investigating the time course of these events for 12 h after heat treatment indicated that cytochromecrelease and caspase-like protease activation occurred rapidly and were consistent with the onset of DNA fragmentation. In addition, LEHDase and DEVDase enzymes were specifically activated in tomato fruit pericarp during the heat treatment and recovery time. There was no significant activation of YVADase or IETDase proteases. Preincubation of pericarp discs with the broad-spectrum, cell-permeable caspase inhibitor Z-VAD-FMK, suppressed heat-induced cell death measured by trypan blue, accompanied by a decrease in LEHDase and DEVDase activities.