GABA合成抑制剂对花粉管生长过程中线粒体活动及ROS分布的影响

GABA合成抑制剂对花粉管生长过程中线粒体活动及ROS分布的影响

崔亚宁，凌  宇，李晓娟^*

（北京林业大学生物科学与技术学院，北京100083）

摘 要  应用激光共聚焦显微镜和全内反射荧光显微镜，以青杄花粉为供试材料，研究γ-氨基丁酸(gamma-amino butyric acid，GABA)合成抑制剂3-MP对线粒体活动规律以及ROS分布范围的影响。结果表明：正常条件下，线粒体的活动规律为由花粉管基部移动到亚顶端后随即发生回流，并主要集中在花粉管的顶端和亚顶端；3-MP处理后，线粒体前移并充满整个花粉管的膨胀区，同时花粉管中快速移动线粒体的比例也逐渐减少。此外，正常条件下，花粉管的顶端区域存在一个以顶端为基础的陡峭的ROS梯度；用3-MP处理后，ROS由花粉管顶端扩散至整个膨胀区。这些结果丰富了GABA影响裸子植物花粉极性生长的研究。

关键词  青杄；花粉管；线粒体；活性氧(reactive oxygen species，ROS)；GABA

中图分类号：Q944.42；Q336   文献标识码：A     doi:10.3969/j.issn.1000-6281.2016.02.007

 The effects of inhibitor of gamma-amino butyric acid (GABA) synthesis on the motility and distribution of mitochondria and ROS in pollen tubes

CUI Ya-ning, LING Yu, LI Xiao-juan^*

(College of Biological Science and Technology, Beijing Forestry University, Beijing 100083, China)

Abstract  The effect of glutamate decarboxylase on pollen tube development in Picea wilsonii was investigated by using 3-mercaptopropionic acid (3-MP) as an inhibitor, together with confocal microscopy studies and total internal reflection fluorescence microscopy (TIRFM) analysis. The results showed that the motility and distribution of mitochondria and ROS were affected by 3-MP. Under normal conditions, mitochondria moved beneath the plasma membrane toward the sub apex where they turned and moved away from center of the tube toward the base, therefore mitochondria were mainly concentrated in apex and sub apex of the pollen tube. In contrast, with 3-MP treatment, the mitochondria extended to the whole expansion area, and the proportion of rapid moving mitochondria decreased. Moreover, under normal conditions, ROS gradient was detected at the top of the pollen tube, but it was located in the whole expansion area of the pollen tube when treated with 3-MP. These results provided useful information about the effects of GABA on mitochondria and ROS dynamics in gymnosperms pollen tube growth.

Keywords Picea wilsonii; pollen tube; mitochondria; reactive oxygen species;GABA

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[1] HEPLER PK, VIDALI L, CHEUNG AY.  Polarized cell growth in higher plants[J]. Annu Rev Cell Dev Biol，2001，17：159-187.

[2] LING Y, et al. Mutation in SUMO E3 ligase, SIZ1, disrupts the mature female gametophyte in Arabidopsis[J]. PLoS One, 2012，7(1): e29470.

[3] LING Y, et al. γ -Aminobutyric acid (GABA) homeostasis regulates pollen germination and polarized growth in Picea wilsonii[J]. Planta，2013，238(5): 831-843.

[4] CHEN T, et al. Disruption of actin filaments by latrunculin B affects cell wall construction in Picea meyeri pollen tube by disturbing vesicle trafficking[J]. Plant Cell Physiol，2007，48(1): 19-30.

[5] SHI SQ, et al. Effects of exogenous GABA on gene expression of Caragana intermedia roots under NaCl stress: regulatory roles for H₂O₂ and ethylene production[J]. Plant Cell Environ，2010，33(2): 149-162.

[6] SHENG X, et al. Roles of the ubiquitin/proteasome pathway in pollen tube growth with emphasis on MG132-induced alterations in ultrastructure, cytoskeleton, and cell wall components[J].  Plant Physiol，2006，141(4): 1578-1590.

[7] PARK MK, et al. Perinuclear, perigranular and sub-plasmalemmal mitochondria have distinct functions in the regulation of cellular calcium transport[J]. EMBO J，2001，20(8): 1863-1874.

[8] van BREUSEGEM F，DAT JF. Reactive oxygen species in plant cell death[J]. Plant Physiol，2006，141(2): 384-390.

[9] WANG CL，et al. S-RNase disrupts tip-localized reactive oxygen species and induces nuclear DNA degradation in incompatible pollen tubes ofPyrus pyrifolia[J]. J Cell Sci，2010，123(Pt 24): 4301-4309.

[10]BOUCHE N, LACOMBE B, FROMM H. GABA signaling: a conserved and ubiquitous mechanism[J]. Trends Cell Biol，2003，13(12): 607-610.

[11] VIDALI L，HEPLER PK. Actin and pollen tube growth[J]. Protoplasma，2001，215(1-4): 64-76.

[12] 苏国兴, 董必慧，刘友良，等.  g-氨基丁酸在高等植物体内的代谢和功能[J]. 植物生理学通讯，2003，39(6): 670-676.

[13] PALANIVELU R, et al. Pollen tube growth and guidance is regulated by POP2, an Arabidopsis gene that controls GABA levels[J]. Cell，2003，114(1): 47-59.

[14] LAZZARO MD. Microtubule organization in germinated pollen of the conifer Picea abies (Norway spruce, Pinaceae)[J]. Am J Bot，1999，86(6): 759-766.

[15] TAYLOR LP，HEPLER PK. Pollen germination and tube growth[J]. Annu Rev Plant Physiol Plant Mol Biol，1997，48: 461-491.

[16] ROUNDS CM，WINSHIP LJ，HEPLER PK. Pollen tube energetics: respiration, fermentation and the race to the ovule[J]. AoB Plants，2011，plr019.

[17] WANG Y, ZHU Y F, LING Y, et al. Disruption of actin filaments induces mitochondrial Ca²⁺ release to the cytoplasm and [Ca²⁺]_cchanges inArabidopsis root hairs[J]. BMC Plant Biol, 2010，10: 53.

[18] van GESTEL K, KOHLER RH, VERBELEN JP. Plant mitochondria move on F-actin, but their positioning in the cortical cytoplasm depends on both F-actin and microtubules[J]. J Exp Bot，2002，53(369): 659-667.

[19] CARDENAs L, et al. NAD(P)H oscillates in pollen tubes and is correlated with tip growth[J]. Plant Physiol，2006，142(4): 1460-1468.

[20] 罗银玲，宋松泉.植物线粒体、活性氧与信号转导[J]. 西北植物学报，2004，24（4）：737-747.

[21] Potocky M, et al. NADPH oxidase activity in pollen tubes is affected by calcium ions, signaling phospholipids and Rac/Rop GTPases[J]. J Plant Physiol，2012，169(16): 1654-1663.