植物K+通道AKT1的研究进展

doi:10.11983/CBB16023

摘要/Abstract

摘要： 钾(K)是植物生长发育必需的大量营养元素之一, 主要通过根细胞的K⁺通道及转运蛋白介导吸收。AKT1是Shaker型K⁺通道家族的重要成员, 在植物根吸收K⁺和体内跨膜转运中发挥重要作用。该文综述了植物AKT1的分子结构、组织特异性表达、调控机制及生物学功能等方面的研究进展, 并对该通道今后的研究方向进行了展望。

Abstract: Potassium (K) is an essential macronutrient for plant growth and development. K⁺ uptake was mainly mediated by K⁺ channels and transporters in root cells. Arabidopsis K⁺ transporter 1 (AKT1) is one of the important members of the Shaker type K⁺ channel families and plays crucial roles in root K⁺ uptake and transmembrane transport of plants. Here, we summarize the latest research advances for the K⁺ channel AKT1, mainly its molecular structure, tissue-specific expression, regulation mechanisms, and biological function. We propose research hotspots and directions for research into the AKT1 channel.

伍国强, 水清照, 冯瑞军. 植物K⁺通道AKT1的研究进展. 植物学报, 2017, 52(2): 225-234.

Guoqiang Wu, Qingzhao Shui, Ruijun Feng. Research Advance of K⁺ Channel AKT1 in Plants. Chinese Bulletin of Botany, 2017, 52(2): 225-234.

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链接本文: https://www.chinbullbotany.com/CN/10.11983/CBB16023

https://www.chinbullbotany.com/CN/Y2017/V52/I2/225

图/表 3

图1 植物Shaker型K+通道拓扑结构示意图(改自Nieves- Cordones and Gaillard, 2014)S1-S6为6个跨膜结构域; S4为电压感受器; CNBD为环核苷酸结合域。

Figure 1 Diagrammatic representation of plant Shaker type K+ channel topological structure (Modified from Nieves- Cordones and Gaillard, 2014)S1-S6 indicate six transmembrane domains; S4 represents voltage sensor; CNBD indicates cyclic-nucleotide binding domain.

图2 植物AKT1的系统进化树AKT1的来源及登录号为: 赤桉(Eucalyptus camaldulensis), EcAKT1 (AAL25648.1); 苹果(Malus domestica), MdAKT1 (XP_ 008352270); 大豆(Glycine max), GmAKT1 (NP_001304431); 胡杨(Populus euphratica), PeAKT1 (ADA79674); 棉花(Gossy- pium hirsutum), GhAKT1 (AHZ30618); 拟南芥(Arabidopsis thaliana), AtAKT1 (NP_180233.1); 霸王(Zygophyllum xanth- oxylon), ZxAKT1 (ACX37089.1); 胡萝卜(Daucus carota), DcAKT1 (CAG27094); 番茄(Lycopersicon esculentum), Le- AKT1 (CAA65254); 马铃薯(Solanum tuberosum), StAKT1 (NP_001275347); 麝香百合(Lilium longiflorum), LlAKT1 (AB- O15470); 大麦(Hordeum vulgare), HvAKT1 (ABE99810.1); 小麦(Triticum aestivum), TaAKT1 (AAF36832.1); 小果野蕉(Musa acuminata subsp. malaccensis), MaAKT1 (XP_ 009386140); 油棕(Elaeis guineensis), EgAKT1 (XP_010925- 144); 海枣(Phoenix dactylifera), PdAKT1 (XP_008809499); 烟草(Nicotiana tabacum), NtAKT1 (BAD81034); 葡萄(Vitis vinifera), VvAKT1 (NP_001268010)。甜菜(Beta vulgaris) Bv- AKT1由本课题组克隆。通过Clustal W软件进行多重序列比对; 采用最大似然法, 用JTT (Jones-Taylor-Thornton)模型(MEGA 5.10)构建植物AKT1的系统进化树。

Figure 2 Phylogenetic tree of plant AKT1The sources and GenBank accession numbers of AKT1 are as follows: Eucalyptus camaldulensis, EcAKT1 (AAL256- 48.1); Malus domestica, MdAKT1 (XP_008352270); Glycine max, GmAKT1 (NP_001304431); Populus euphratica, Pe- AKT1 (ADA79674); Gossypium hirsutum, GhAKT1 (AHZ30- 618); Arabidopsis thaliana, AtAKT1 (NP_180233.1); Zygophyllum xanthoxylon, ZxAKT1 (ACX37089.1); Daucus carota, DcAKT1 (CAG27094); Lycopersicon esculentum, LeAKT1 (CAA65254); Solanum tuberosum, StAKT1 (NP_001275- 347); Lilium longiflorum, LlAKT1 (ABO15470); Hordeum vulgare, HvAKT1 (ABE99810.1); Triticum aestivum, TaAKT1 (AAF36832.1); Musa acuminata subsp. malaccensis, MaAKT1 (XP_009386140); Elaeis guineensis, EgAKT1 (XP_ 010925144); Phoenix dactylifera, PdAKT1 (XP_008809- 499); Nicotiana tabacum, NtAKT1 (BAD81034); Vitis vinifera, VvAKT1 (NP_001268010). Beta vulgaris BvAKT1 was cloned by Wu's research group. Multiple alignment of AKT1 sequences was performed by the Clustal W. Phylogenetic tree of plants AKT1 was constructed by the Maximum Likelihood and JTT (Jones-Taylor-Thornton) model (MEGA 5.10).

表1 高等植物中的AKT1

Table 1 AKT1 in higher plants

基因	物种	表达部位	参考文献
AtAKT1	拟南芥(Arabidopsis thaliana)	根表皮、皮层及内皮层	Lagarde et al., 1996
LeAKT1	番茄(Lycopersicon esculentum)	根毛	Hartje et al., 2000
VfAKT1	蚕豆(Vicia faba)	叶和韧皮部	Ache et al., 2001
GhAKT1	棉花(Gossypium hirsutum)	叶细胞皮层、内皮层及光合细胞	Xu et al., 2014
OsAKT1	水稻(Oryza sativa)	根和叶	Golldack et al., 2003
McAKT1	冰叶日中花(Mesembryanthemum crystallinum)	茎和叶	Su et al., 2001
PtAKT1	小花碱茅(Puccinellia tenuiflora)	根	Wang et al., 2015
SsAKT1	盐地碱蓬(Suaeda salsa)	根和叶	Duan et al., 2015
StAKT1	马铃薯(Solanum tuberosum)	保卫细胞、叶表皮和根	Zimmermann et al., 1998
TaAKT1	小麦(Triticum aestivum)	根皮层细胞	Buschmann et al., 2000
ZmAKT1	玉米(Zea mays)	胚芽鞘细胞	Philippar et al., 1999
CaAKT1	辣椒(Capsicum annuum)	根	Martinez-Cordero et al., 2005
NtAKT1	烟草(Nicotiana tabacum)	根	Sano et al., 2007
HvAKT1	大麦(Hordeum vulgare)	叶	Boscari et al., 2009
DcAKT1	胡萝卜(Daucus carota)	茎、根毛和叶	Formentin et al., 2004
VvAKT1.1 VvAKT1.2	葡萄(Vitis vinifera) 葡萄(V. vinifera)	根和浆果浆果	Cuéllar et al., 2010 Cuéllar et al., 2013

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