Chin Bull Bot ›› 2019, Vol. 54 ›› Issue (5): 642-651.doi: 10.11983/CBB18260

• SPECIAL TOPICS • Previous Articles     Next Articles

Research Advances in the Functions of Exocyst Complex in Plants

Li Tonghui1,Liu Xiaonan2,Xu Jing2,Li Shipeng2,Jiang Su2,*()   

  1. 1. College of Life Sciences, Shandong Normal University, Jinan 250014, China
    2. College of Life Sciences, Qilu Normal University, Jinan 250200, China
  • Received:2018-12-04 Accepted:2019-03-19 Online:2020-03-10 Published:2019-09-01
  • Contact: Jiang Su


Vesicle trafficking is the biological process involving in budding, translocation, tethering and membrane fusion in all eukaryotic cells. Nine multisubunit tethering complexes (MTCs) are known to play roles in the intracellular transport, and the exocyst complex facilitates the tethering between transport vesicles and the plasma membrane (PM). The regulatory mechanism of the exocyst complex had been extensively studied in yeast and animals, whereas rapid research progress on plant exocyst has been made in recent years. Recent findings show that the plant exocyst complex has unique regulatory characteristics and is widely involved in plant growth, development and stress responses. Here we summarize research progress on the plant exocyst complex to provide a reference for future study of exocyst function in plants.

Key words: vesicle trafficking, multisubunit tethering complexes, exocyst complex

Figure 1

Working models of yeast exocyst complex"

Table 1

Numbers of genes encoding exocyst subunits in 3 model organisms"

模式生物 SEC3 SEC5 SEC6 SEC8 SEC10 SEC15 EXO70 EXO84
酿酒酵母 1 1 1 1 1 1 1 1
小鼠 1 1 1 1 1 1 1 1
拟南芥 2 2 1 1 2 2 23 3

Table 2

Biological processes involved in plant exocyst complex"

生物学过程 参与蛋白 突变体表型 参考文献
顶端生长 ZmSEC3 SEC3同源物RTH1突变导致根毛变短 Wen et al., 2005
AtSEC3A 突变后花粉萌发和花粉管生长存在缺陷 Bloch et al., 2016
AtSEC5 突变后花粉萌发和花粉管生长存在缺陷 Hála et al., 2008
AtSEC6 突变后花粉萌发和花粉管生长存在缺陷 Hála et al., 2008
AtSEC8 突变后花粉萌发和花粉管生长存在缺陷 Hála et al., 2008
AtSEC15A 突变后花粉萌发和花粉管生长存在缺陷 Hála et al., 2008
AtEXO70C1 突变后花粉管生长迟缓, 花粉传递效率下降 Li et al., 2010
生长素转运蛋白再循环 AtEXO70A1 突变后生长素的运输和分布发生改变, 如丧失顶端优势、根生长迟缓及侧根发生推迟 Drdová et al., 2013
纤维素合酶复合体向质膜的运输 AtSEC5 SEC5A/SEC5B双突变导致幼苗致死 Zhu et al., 2018
干性柱头水分分泌和花粉水合过程 BoEXO70A1 突变后自交不亲和 Samuel et al., 2009
豆科植物的共生及生长发育 GmEXO70J EXO70J基因沉默后, 加速叶片衰老及根瘤数减少 Wang et al., 2016
植物防御反应 OsSEC3A 突变后增强植物防御反应, 如水杨酸水平升高, 增强对真菌病原体的抗性 Ma et al., 2018
小立豌藓的生 长发育过程 PpEXO70.3d PpEXO70.3d缺失导致原丝体中细胞伸长及分化缺陷 Rawat et al., 2017
胞质分裂 AtSEC6 突变后胚胎发育异常, 存在多核细胞 Wu et al., 2013
AtEXO84B 突变后细胞闭合不全, 存在多核现象, 细胞内累积大量囊泡 Fendrych et al., 2010
细胞壁形成 AtEXO70A1 突变导致根毛和柱头毛变短 Synek et al., 2006
AtEXO70H4 突变后检测不到次生细胞壁的形成 Kulich et al., 2015
细胞自噬 AtEXO70B1 突变后液泡中内化的自噬体减少, 突变植株出现异位过敏反应 Kulich et al., 2013

Figure 2

Interactions among different exocyst complex subunits in plants"

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