Research progress relating to stelar K+ outward rectifier （SKOR） channels in plants

doi:10.11686/cyxb2022078

Abstract

Abstract:

Maintaining K⁺ homeostasis is one of important physiological component processes in plant resistance to abiotic stress. Stelar K⁺ outward rectifier （SKOR） is one of the outward rectifier K⁺ channels located in the plasma membrane of pericycle cells in plant roots. This channel is involved in mediating K⁺ efflux from cytoplasm and K⁺ loading in xylem. On the one hand， SKOR regulates intracellular K⁺ homeostasis； while on the other hand， it maintains the K⁺ balance between root and shoot by controlling K⁺ flow in xylem. SKOR plays a crucial role in plant response to salt， drought and nutrient deficiency. Therefore， research into SKOR function and regulation and its application is of great significance for crop production and stress resistance enhancement. In this study， the discovery， structure， nomenclature， biological function， gene expression regulation， and response to abiotic stresses of the SKOR family are reviewed， and directions for future research into functioning of this channel are proposed. This review contributes theoretical understanding and knowledge of gene resources for the genetic improvement of crop quality and stress resistance.

Key words: outward rectifier K⁺ channel, K⁺starvation, K⁺ loading in xylem, regulation, stress response

Pan-pan REN, Guo-qiang WU, Ming WEI. Research progress relating to stelar K⁺ outward rectifier （SKOR） channels in plants[J]. Acta Prataculturae Sinica, 2023, 32(2): 178-190.

Figures/Tables 3

References 112

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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）	表达部位 Expression site	参考文献 Reference
拟南芥 A.thaliana	AtSKOR	AJ223357	828	根Root	［21］
小花茅碱 P. tenuiflora	PtSKOR	JQ279059.1	715	根Root	［27］
水稻 O. sativa	OsK5.1	Os04g36740	719	根维管束组织Root vascular tissues	［28］
水稻 O. sativa	OsK5.2	Os06g14030	858	根和地上部Root and shoot	［32］
霸王Z. xanthoxylum	ZxSKOR	/	847	根、茎、叶Root， stem and leaf	［29］
枸杞L. barbarum	LbSKOR	KU523244	815	根、叶Root， leaf	［30］
甜瓜C. melo	CmSKOR	MF447462	825	根、茎、叶Root， stem and leaf	［31］
烟草Nicotiana tabacum	NtSKOR	XM_009764356.1	827	主要在根Mainly in root	［33］
黑果枸杞Lycium ruthenicum	LrSKOR	KY563342	815	根、叶Root， leaf	［34］
葡萄Vitis vinifera	VvK5.1	XP_010660282.1	821	根中柱、侧根Root stelar， lateral root	［9］
蒺藜苜蓿Medicago truncatula	MtSKOR	Medtr5g077770	835	根和地上部Root and shoot	［35］
长穗偃麦草Elytrigia elongata	EeSKOR	MK203848	717	根、叶和叶柄Root， leaves and petioles	［36］
灰楸Catalpa fargesii	CfSKOR	MW773724	632	根Root	［37］
山新杨Populus davidiana	PdSKOR	MT335814	841	根Root	［38］
小米Setaria italica	SiSKOR	AT3G02850	854	根Root	［39］
紫柳Salix purpurea	SpuSKOR	SapurV1A.0223s0270	1032	根、叶、雌蕊、花瓣Root， leaf， pistil and petal	［40］
木豆Cajanus cajan	CcSKOR	XP 020202567	837	根Root	［41］
绿豆Vigna radiata	VrSKOR	XP_014505028.1	851	根Root	［42］
甜菜Beta vulgaris	BvSKOR	Bv2_047040_fjjf	828	根和地上部Root and shoot	未发表数据 Unpublished data

物种 Species	基因名称 Gene name	登录号 Accession No.	氨基酸数目 Amino acids （aa）	表达部位 Expression site	参考文献 Reference
拟南芥 A.thaliana	AtSKOR	AJ223357	828	根Root	［21］
小花茅碱 P. tenuiflora	PtSKOR	JQ279059.1	715	根Root	［27］
水稻 O. sativa	OsK5.1	Os04g36740	719	根维管束组织Root vascular tissues	［28］
水稻 O. sativa	OsK5.2	Os06g14030	858	根和地上部Root and shoot	［32］
霸王Z. xanthoxylum	ZxSKOR	/	847	根、茎、叶Root， stem and leaf	［29］
枸杞L. barbarum	LbSKOR	KU523244	815	根、叶Root， leaf	［30］
甜瓜C. melo	CmSKOR	MF447462	825	根、茎、叶Root， stem and leaf	［31］
烟草Nicotiana tabacum	NtSKOR	XM_009764356.1	827	主要在根Mainly in root	［33］
黑果枸杞Lycium ruthenicum	LrSKOR	KY563342	815	根、叶Root， leaf	［34］
葡萄Vitis vinifera	VvK5.1	XP_010660282.1	821	根中柱、侧根Root stelar， lateral root	［9］
蒺藜苜蓿Medicago truncatula	MtSKOR	Medtr5g077770	835	根和地上部Root and shoot	［35］
长穗偃麦草Elytrigia elongata	EeSKOR	MK203848	717	根、叶和叶柄Root， leaves and petioles	［36］
灰楸Catalpa fargesii	CfSKOR	MW773724	632	根Root	［37］
山新杨Populus davidiana	PdSKOR	MT335814	841	根Root	［38］
小米Setaria italica	SiSKOR	AT3G02850	854	根Root	［39］
紫柳Salix purpurea	SpuSKOR	SapurV1A.0223s0270	1032	根、叶、雌蕊、花瓣Root， leaf， pistil and petal	［40］
木豆Cajanus cajan	CcSKOR	XP 020202567	837	根Root	［41］
绿豆Vigna radiata	VrSKOR	XP_014505028.1	851	根Root	［42］
甜菜Beta vulgaris	BvSKOR	Bv2_047040_fjjf	828	根和地上部Root and shoot	未发表数据 Unpublished data

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