Advances in HKT1 Study on the Mechanism of Salt Tolerance in Plants

doi:10.13560/j.cnki.biotech.bull.1985.2020-1379

Abstract

Abstract:

Soil salinization is an important factor affecting the reduction of crop yield. Under salt stress,plants have evolved a series of strategies to deal with salt. In these strategies,ion transporters play a pivotal role in plant response to salt stress. HKT1 transporters are a kind of ion transporters with the function of transporting Na⁺,which are mainly located near vascular bundles and widely found in monocotyledons and dicotyledons. In plants,they participate in the long-distance transport of Na⁺,regulate the concentration of Na⁺,and help to maintain ion balance. In this paper,the functions and corresponding regulatory processes of HKT1 proteins in different plants are discussed,and the different action models of HKT1 participating in Na⁺ long-distance transportation are summarized. By making a synthesis of the research on HKT1 in recent years and rational use of molecular breeding,it lays a theoretical foundation for increasing the salt stress tolerance of crops and improving the quality and yield of crops.

Key words: salt stress, HKT1, HKT1 regulation, Na⁺, long-distance transport

ZHANG Yong-lan, XIE Li-nan. Advances in HKT1 Study on the Mechanism of Salt Tolerance in Plants[J]. Biotechnology Bulletin, 2021, 37(6): 213-224.

Figures/Tables 4

References 76

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基因名称 Gene name	物种 Species	表达位置 Express position	在植物中的功能 Function in plants	异源表达时的功能 Function in heterologous expression
EcHKT1;2	蓝桉树 Eucalyptus camalduensis	根、茎、叶均有表达^[15]	转运K^+[15]	大肠杆菌:K⁺转运非洲爪蟾卵母细胞:Na⁺、K⁺、Rb⁺、Li⁺转运
McHKT1;1	冰叶日中花 Mesembryantemum crystallinum	根:表皮细胞、维管束组织^[16] 叶:木质部薄壁细胞、导管细胞	根中表皮细胞转运K⁺进入细胞^[16]	酿酒酵母:K⁺转运非洲爪蟾卵母细胞^[16]:Rb⁺、Cs⁺、K⁺、Na⁺、Li ⁺转运
TsHKT1;2	盐芥 Thellungiella salsuginea	根和叶的维管束,木质部薄壁细胞^[18]	转运K^+[17]	酿酒酵母^[18]:K⁺转运
SvHKT1;1	鼠尾栗 Sporobolus virginicus	500 mmol/L氯化钠处理,根中表达量明显升高^[19]	防止地上部分Na⁺积累过高^[19]	酿酒酵母:Na⁺转运
AtHKT1;1	拟南芥 Arabidopsis thaliana	根和叶的维管束,木质部薄壁细胞^[20]	在地上部分,将Na⁺转运到韧皮部中; 在根中,将Na⁺从木质部中转运出来^[21]	大肠杆菌^[20]:K⁺转运酿酒酵母:Na⁺转运
OsHKT1;1	水稻 Oryza sativa L.	根:表皮、分化为通气组织的内皮,根中柱(尤其是韧皮部) 叶:叶肉细胞和维管束^[22]		酿酒酵母:Na⁺转运非洲爪蟾卵母细胞:Na⁺转运^[23]
OsHKT1;4	水稻 Oryza sativa L.	叶鞘^[24]	控制叶鞘叶片之间的Na⁺转移^[25]
OsHKT1;5	水稻 Oryza sativa L.	根和叶的维管束^[26]	在根中,将Na⁺从木质部中转运出来^[27]	非洲爪蟾卵母细胞:Na⁺转运
TaHKT1;4	小麦 Triticum aestivum	根、叶鞘和叶片^[28]	将Na⁺从木质部中转运到木质部薄壁细胞^[29]
TaHKT1;5	小麦 Triticum aestivum	根中表达,地上部分不表达^[30]	将Na⁺从木质部中转运到木质部薄壁细胞^[28]	酿酒酵母:Na⁺转运非洲爪蟾卵母细胞^[31]:Na⁺转运
SlHKT1;1	番茄 Solanum lycopersicum	根、茎、叶、花、果实中广泛表达^[32]		酿酒酵母:Na⁺转运非洲爪蟾卵母细胞^[32]:Na⁺转运
SlHKT1;2	番茄 Solanum lycopersicum	根、茎、叶、花、果实中广泛表达^[32]		酿酒酵母、非洲爪蟾卵母细胞^[32]:无转运活性
HvHKT1;1	大麦 Hordeum vulgare L.	根和叶的维管束^[33]	根中横向Na⁺运输,减少地上部分的Na⁺积累^[33]	酿酒酵母、非洲爪蟾卵母细胞^[34]:K⁺转运
HvHKT1;5	大麦 Hordeum vulgare L.	根和叶的维管束^[35]	将Na⁺从木质部薄壁细胞转运到木质部中^[35]	非洲爪蟾卵母细胞:Na⁺转运^[35],但受K⁺抑制

基因名称 Gene name	物种 Species	表达位置 Express position	在植物中的功能 Function in plants	异源表达时的功能 Function in heterologous expression
EcHKT1;2	蓝桉树 Eucalyptus camalduensis	根、茎、叶均有表达^[15]	转运K^+[15]	大肠杆菌:K⁺转运非洲爪蟾卵母细胞:Na⁺、K⁺、Rb⁺、Li⁺转运
McHKT1;1	冰叶日中花 Mesembryantemum crystallinum	根:表皮细胞、维管束组织^[16] 叶:木质部薄壁细胞、导管细胞	根中表皮细胞转运K⁺进入细胞^[16]	酿酒酵母:K⁺转运非洲爪蟾卵母细胞^[16]:Rb⁺、Cs⁺、K⁺、Na⁺、Li ⁺转运
TsHKT1;2	盐芥 Thellungiella salsuginea	根和叶的维管束,木质部薄壁细胞^[18]	转运K^+[17]	酿酒酵母^[18]:K⁺转运
SvHKT1;1	鼠尾栗 Sporobolus virginicus	500 mmol/L氯化钠处理,根中表达量明显升高^[19]	防止地上部分Na⁺积累过高^[19]	酿酒酵母:Na⁺转运
AtHKT1;1	拟南芥 Arabidopsis thaliana	根和叶的维管束,木质部薄壁细胞^[20]	在地上部分,将Na⁺转运到韧皮部中; 在根中,将Na⁺从木质部中转运出来^[21]	大肠杆菌^[20]:K⁺转运酿酒酵母:Na⁺转运
OsHKT1;1	水稻 Oryza sativa L.	根:表皮、分化为通气组织的内皮,根中柱(尤其是韧皮部) 叶:叶肉细胞和维管束^[22]		酿酒酵母:Na⁺转运非洲爪蟾卵母细胞:Na⁺转运^[23]
OsHKT1;4	水稻 Oryza sativa L.	叶鞘^[24]	控制叶鞘叶片之间的Na⁺转移^[25]
OsHKT1;5	水稻 Oryza sativa L.	根和叶的维管束^[26]	在根中,将Na⁺从木质部中转运出来^[27]	非洲爪蟾卵母细胞:Na⁺转运
TaHKT1;4	小麦 Triticum aestivum	根、叶鞘和叶片^[28]	将Na⁺从木质部中转运到木质部薄壁细胞^[29]
TaHKT1;5	小麦 Triticum aestivum	根中表达,地上部分不表达^[30]	将Na⁺从木质部中转运到木质部薄壁细胞^[28]	酿酒酵母:Na⁺转运非洲爪蟾卵母细胞^[31]:Na⁺转运
SlHKT1;1	番茄 Solanum lycopersicum	根、茎、叶、花、果实中广泛表达^[32]		酿酒酵母:Na⁺转运非洲爪蟾卵母细胞^[32]:Na⁺转运
SlHKT1;2	番茄 Solanum lycopersicum	根、茎、叶、花、果实中广泛表达^[32]		酿酒酵母、非洲爪蟾卵母细胞^[32]:无转运活性
HvHKT1;1	大麦 Hordeum vulgare L.	根和叶的维管束^[33]	根中横向Na⁺运输,减少地上部分的Na⁺积累^[33]	酿酒酵母、非洲爪蟾卵母细胞^[34]:K⁺转运
HvHKT1;5	大麦 Hordeum vulgare L.	根和叶的维管束^[35]	将Na⁺从木质部薄壁细胞转运到木质部中^[35]	非洲爪蟾卵母细胞:Na⁺转运^[35],但受K⁺抑制