胞外ATP参与调控拟南芥对过量强度光照的部分生理学响应  

Extracellular ATP is involved in regulating partial physiological responses of Arabidopsis thaliana to excess light

作　　者：王馨 李丽[1] 李颖 贾凌云[1] 冯汉青[1] WANG Xin;LI Li;LI Ying;JIA Lingyun;FENG Hanqing(College of Life Sciences,Northwest Normal University,Lanzhou 730070,China)

机构地区：[1]西北师范大学生命科学学院,兰州730070

出　　处：《植物生理学报》2022年第8期1528-1536,共9页Plant Physiology Journal

基　　金：国家自然科学基金(31870246和31560070);甘肃省重点研发计划项目(18YF1NA051);甘肃省引导科技创新发展专项资金(2019ZX-05);甘肃省科技重大专项项目(22ZD1NA001);西北师范大学新农村发展研究院开放基金。

摘　　要：植物在自然环境中往往受到过量强度光照的影响。作为植物中较新鉴定的信号分子,胞外ATP (extracellular ATP,eATP)是否参与了植物对过量强度光照的生理学响应尚不清楚。本研究发现,过量强度光照使得拟南芥(Arabidopsis thaliana)植株叶片胞外ATP水平上升、光系统II (photosystem II,PSII)受到抑制、气孔开度下降,而过氧化氢(HO)含量、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性升高。通过野生型(Col)和植物胞外ATP受体突变型(dorn1-3)拟南芥对比发现,在过量强度光照下2种植株叶片PSII均受到损伤,但较之野生型植株,dorn1-3植株受损伤程度较低。过量强度光照引起了野生型植株叶片中APX和POD活性的升高,但并未引起dorn1-3植株内2种酶活性显著性变化。同时,在过量强度光照下dorn1-3植株叶片气孔开度显著高于野生型,但过量强度光照下dorn1-3植株叶片H_(2)O_(2)含量和野生型相比无显著差异。因此,上述结果表明,在过量强度光照下,拟南芥eATP水平的上升通过刺激其受体DORN,参与了植物PSII的抑制和气孔的关闭,并同时调节了抗氧化酶APX和POD的活性。Plants are often affected by excessive light in the natural environment.Extracellular ATP is a newly identified signaling molecule in plants.However,whether extracellular ATP could be involved in the physiological response of plants to excessive light remains unclear.In this study,we found that excessive light increased extracellular ATP level,inhibited the activity of photosystem II(PSII),and decreased stomatal opening,while H_(2)O_(2)content and the activities of peroxidase(POD) and ascorbate peroxidase(APX) increased in Arabidopsis thaliana leaves.By the comparison of wild-type(Col) and extracellular ATP(eATP) receptor mutant(dorn1-3),it was shown that PSII was inhibited in Col and dorn1-3 mutant by excessive light,but the inhibition degree was lower in dorn1-3 mutant than that in wild-type plants.Excessive light increased the activities of APX and POD enzymes in wild-type leaves,but it did not cause significant changes in the activities of the two enzymes in dorn1-3 mutant plants.The stomatal aperture of dorn1-3 mutant was higher than that of wild type under excessive light.Under excessive light,there was no significant difference in H_(2)O_(2)content between the wild type and dorn1-3 mutant plants.These results indicate that the increase of eATP level under excessive light participates in the inhibition of PSII and stomatal closure by stimulating its receptor DORN,and eATP is also involved in the regulation of activities of antioxidant enzymes APX and POD.

关 键 词：过量强度光照 胞外ATP 叶绿素荧光 H2O2 抗氧化酶 

分 类 号：Q945[生物学—植物学]