Function of high-affinity potassium transporters in maintaining ion homeostasis and other plant responses to abiotic stresses

doi:10.11686/cyxb2022207

Abstract

Abstract:

Potassium ions （K⁺）^{play an important role in plant growth and development as well as in resistance to various abiotic stresses. High-affinity K⁺ transporters （HKT） are one of the most important cation transporter families， and the members of this family are extensively involved in the absorption and transport of K⁺ and sodium ions （Na⁺） in plants. Many studies have shown that the expression of HKT family genes is regulated by several factors， such as calcium ions （Ca²⁺）， humic acid， and cytosine methylation. The HKT proteins mediate long-distance Na⁺ transport， maintain homeostasis of K⁺and magnesium ions （Mg²⁺）， and play a key role in abiotic stress tolerance in plants. In this review， we summarize the results of research on the discovery of HKT family members， their structure and classification， biological function， gene expression patterns， regulatory mechanisms， and their roles in responses to abiotic stresses. We also propose directions for further research. The information in this review provides a theoretical basis and identifies genetic resources for the genetic improvement of crops to produce new， stress-resistant varieties.}

Key words: high-affinity K⁺ transporter, Na⁺/K⁺ balance, ion homeostasis, Na⁺ long-distance transport, salt tolerance

Xiao-han YANG, Guo-qiang WU, Ming WEI, Bei-chen WANG. Function of high-affinity potassium transporters in maintaining ion homeostasis and other plant responses to abiotic stresses[J]. Acta Prataculturae Sinica, 2023, 32(5): 190-202.

Figures/Tables 4

References 134

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物种 Species	基因名称 Gene name	登录号 Accession No.	氨基酸数目 Amino acids （aa）	分子量 MW （kDa）	等电点 pI	参考文献 References
拟南芥A. thaliana	AtHKT1；1	AAF68393	506	57.49	8.86	［26］
节节麦A. tauschii	AetHKT2；4	XP_020183163.1	508	55.94	8.96	［27］
水稻O. sativa	OsHKT1；1	CAD37183	552	61.86	8.95	［28］
	OsHKT1；3	CAD37185	531	59.30	9.41
	OsHKT1；4	CAD37197	500	54.24	8.96
	OsHKT1；5	BAB93392	554	60.22	8.79
	OsHKT2；1	BAB61789	530	59.30	9.43
	OsHKT2；2	BAB61791	530	59.15	9.49
	OsHKT2；3	XP_015632753.1	509	56.37	9.13
	OsHKT2；4	XP_015641899.1	509	56.12	8.74
毛果杨P. trichocarpa	PtHKT1；1	XP_002325229	535	60.09	9.48	［29］
番茄S. lycopersicum	SlHKT1；1	NP_001289833.1	503	56.88	9.03	［30］
番茄S. lycopersicum	SlHKT1；2	NP_001295273.1	555	63.42	9.11	［30］
高粱S. bicolor	SbHKT1；1	KXG27071	582	63.74	9.71	［31］
	SbHKT1；2	XP_002457736	546	59.62	8.99
	SbHKT1；3	XP_002451638	532	59.82	8.91
	SbHKT2；1	XP_002438960	545	57.91	9.24
盐芥T. salsuginea	TsHKT1；1	AFJ23835	505	57.27	8.78	［32］
盐芥T. salsuginea	TsHKT1；2	BAJ34563	500	56.59	8.98	［32］
小麦T. aestivum	TaHKT1；5B1	ABG33947	518	57.46	9.11	［33］
	TaHKT1；5B2	ABG33948	514	57.23	8.38
	TaHKT1；5D	ABG33945	516	57.30	8.90
	TaHKT2；1	AAA52749	533	58.92	8.93
	TaHKT2；2	AMB15006.1	508	56.01	9.04
一粒小麦T. monococcum	TmHKT1；4-A2	ABK41857	554	60.59	9.75	［34］
	TmHKT1；5-A	ABG33946	517	57.29	8.04
	TmHKT2；1-A1	AMB15009.1	533	58.89	9.15
玉米Z. mays	ZmHKT1；5	DAA54361	493	53.85	9.13	［35］
玉米Z. mays	ZmHKT2；1	XP_008645031	555	58.55	9.34	［35］
甜菜B. vulgaris	BvHKT1；1	Bv8_198240_anxn	280	31.95	9.39	［36］
	BvHKT1；2	Bv9_212780_gxzu	505	57.13	9.12
	BvHKT1；3	Bv9_212770_duhc	511	57.85	9.42

物种 Species	基因名称 Gene name	登录号 Accession No.	氨基酸数目 Amino acids （aa）	分子量 MW （kDa）	等电点 pI	参考文献 References
拟南芥A. thaliana	AtHKT1；1	AAF68393	506	57.49	8.86	［26］
节节麦A. tauschii	AetHKT2；4	XP_020183163.1	508	55.94	8.96	［27］
水稻O. sativa	OsHKT1；1	CAD37183	552	61.86	8.95	［28］
	OsHKT1；3	CAD37185	531	59.30	9.41
	OsHKT1；4	CAD37197	500	54.24	8.96
	OsHKT1；5	BAB93392	554	60.22	8.79
	OsHKT2；1	BAB61789	530	59.30	9.43
	OsHKT2；2	BAB61791	530	59.15	9.49
	OsHKT2；3	XP_015632753.1	509	56.37	9.13
	OsHKT2；4	XP_015641899.1	509	56.12	8.74
毛果杨P. trichocarpa	PtHKT1；1	XP_002325229	535	60.09	9.48	［29］
番茄S. lycopersicum	SlHKT1；1	NP_001289833.1	503	56.88	9.03	［30］
番茄S. lycopersicum	SlHKT1；2	NP_001295273.1	555	63.42	9.11	［30］
高粱S. bicolor	SbHKT1；1	KXG27071	582	63.74	9.71	［31］
	SbHKT1；2	XP_002457736	546	59.62	8.99
	SbHKT1；3	XP_002451638	532	59.82	8.91
	SbHKT2；1	XP_002438960	545	57.91	9.24
盐芥T. salsuginea	TsHKT1；1	AFJ23835	505	57.27	8.78	［32］
盐芥T. salsuginea	TsHKT1；2	BAJ34563	500	56.59	8.98	［32］
小麦T. aestivum	TaHKT1；5B1	ABG33947	518	57.46	9.11	［33］
	TaHKT1；5B2	ABG33948	514	57.23	8.38
	TaHKT1；5D	ABG33945	516	57.30	8.90
	TaHKT2；1	AAA52749	533	58.92	8.93
	TaHKT2；2	AMB15006.1	508	56.01	9.04
一粒小麦T. monococcum	TmHKT1；4-A2	ABK41857	554	60.59	9.75	［34］
	TmHKT1；5-A	ABG33946	517	57.29	8.04
	TmHKT2；1-A1	AMB15009.1	533	58.89	9.15
玉米Z. mays	ZmHKT1；5	DAA54361	493	53.85	9.13	［35］
玉米Z. mays	ZmHKT2；1	XP_008645031	555	58.55	9.34	［35］
甜菜B. vulgaris	BvHKT1；1	Bv8_198240_anxn	280	31.95	9.39	［36］
	BvHKT1；2	Bv9_212780_gxzu	505	57.13	9.12
	BvHKT1；3	Bv9_212770_duhc	511	57.85	9.42

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