Identification of the HKT gene family members in Populus species and analysis of their expression patterns under salt stress

doi:10.3969/j.issn.1004-1524.20250023

Acta Agriculturae Zhejiangensis ›› 2025, Vol. 37 ›› Issue (10): 2104-2115.DOI: 10.3969/j.issn.1004-1524.20250023

• Horticultural Science • Previous Articles Next Articles

Identification of the HKT gene family members in Populus species and analysis of their expression patterns under salt stress

LIAO Xiaolong¹(), WANG Xingsheng¹, CHEN Yong¹, LI Bin¹, HONG Sidan², MEI Lina², GUO Ying²^,^*()

1. Ili Experimental Center of Tree Breeding for Improved Varieties(Plain Forestry Farm), Ili Kazak Autonomous Prefecture, Ili 835311, Xinjiang, China
2. Jiangsu Key Laboratory for Poplar Germplasm Enhancement and Variety Improvement, Co-Innovation Center for the Sustainable Forestry in Southern China, College of Forestry and Grassland, College of Soil and Water Conservation, Nanjing Forestry University, Nanjing 210037, China

Received:2025-01-09 Online:2025-10-25 Published:2025-11-13

Abstract

Abstract:

To investigate the function of high-affinity K transporters (HKT) in the salt stress response of Populus species and to identify key genes for salt-tolerant breeding, a genome-wide identification of HKT gene family members was conducted in 11 Populus species, including Populus alba × P. glandulosa clone 84K (poplar clone 84K). Bioinformatics analyses were performed to characterize conserved domains, physicochemical properties, conserved motifs, chromosomal localization, and cis-acting elements. Additionally, the spatiotemporal expression profiles of HKT genes were analyzed using qRT-PCR and RNA-seq data from salt-treated poplar clone 84K. A total of 30 HKT family genes were identified, 29 of which were located on chromosome 18 across the species. Phylogenetic analysis revealed that all 30 HKT genes belong to the HKT1 subfamily and were further divided into two subgroups: HKT1;4 and HKT1;5. Cis-acting element analysis indicated that the promoter regions contained important stress-responsive elements, such as TC-rich repeats, MBS, and G-box. Notably, PaghAHKT1;4 exhibited a significant upregulation in expression with prolonged salt stress in poplar clone 84K. In conclusion, 30 HKT genes were identified in Populus, which play important roles in salt stress response. Among them, PaghAHKT1;4 might serve as a potential target gene for salt-tolerant breeding in poplar clone 84K.

Key words: Populus species, high-affinity K⁺ transporter(HKT) family, salt stress, expression pattern

CLC Number:

S792.11

LIAO Xiaolong, WANG Xingsheng, CHEN Yong, LI Bin, HONG Sidan, MEI Lina, GUO Ying. Identification of the HKT gene family members in Populus species and analysis of their expression patterns under salt stress[J]. Acta Agriculturae Zhejiangensis, 2025, 37(10): 2104-2115.

Figures/Tables 10

References 39

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种/品种 Species/Cultivar	单倍型 Haplotype	组装方式 Assembly strategy
欧洲山杨P. tremula	/	基于参考基因组的基因组组装
毛果杨P. trichocarpa	/	Reference based assembly
胡杨P. euphratica	/	从头组装De novo assembly
小叶杨P. simonii	/
银白杨P. alba	/
新疆杨P. alba var. pyramidalis	/
美洲黑杨I69 P. deltoides I69	/
美洲黑杨2-2 P. deltoides 2-2	/
银腺杨(银腺杨84K)P. alba×P. tremula var. glandulosa clone 84K	单倍型A hapA
	单倍型G hapG
二倍体毛白杨P. tomentosa	单倍型A hapA
	单倍型D hapD
三倍体毛白杨P.×tomentosa Carr. clone 741	单倍型1 hap1
	单倍型2 hap2
	单倍型3 hap3

种/品种 Species/Cultivar	单倍型 Haplotype	组装方式 Assembly strategy
欧洲山杨P. tremula	/	基于参考基因组的基因组组装
毛果杨P. trichocarpa	/	Reference based assembly
胡杨P. euphratica	/	从头组装De novo assembly
小叶杨P. simonii	/
银白杨P. alba	/
新疆杨P. alba var. pyramidalis	/
美洲黑杨I69 P. deltoides I69	/
美洲黑杨2-2 P. deltoides 2-2	/
银腺杨(银腺杨84K)P. alba×P. tremula var. glandulosa clone 84K	单倍型A hapA
	单倍型G hapG
二倍体毛白杨P. tomentosa	单倍型A hapA
	单倍型D hapD
三倍体毛白杨P.×tomentosa Carr. clone 741	单倍型1 hap1
	单倍型2 hap2
	单倍型3 hap3

基因名 Gene name	正向引物序列 Forward primer sequence(5'-3')	反向引物序列 Reverse primer sequence(5'-3')
PaghHKT1;5	GGTGCTCTTCGTGGTTAT	CACAAAGATGGCTAAGGT
PaghAHKT1;4	GCCAGCATTCTTCTTATT	TGACCACAAACAGCACCA
PaghGHKT1;4	TCCCAACTCATTGTCTTC	CAAACAGCACCAAGATAG
UBQ	GTTGATTTTTGCTGGGAAGC	GATCTTGGCCTTCACGTTGT

基因名 Gene name	正向引物序列 Forward primer sequence(5'-3')	反向引物序列 Reverse primer sequence(5'-3')
PaghHKT1;5	GGTGCTCTTCGTGGTTAT	CACAAAGATGGCTAAGGT
PaghAHKT1;4	GCCAGCATTCTTCTTATT	TGACCACAAACAGCACCA
PaghGHKT1;4	TCCCAACTCATTGTCTTC	CAAACAGCACCAAGATAG
UBQ	GTTGATTTTTGCTGGGAAGC	GATCTTGGCCTTCACGTTGT

蛋白质ID Protein ID		基因ID Gene ID		氨基酸长度 Amino acid length/aa		分子量 Molecular weight/ku	等电点 Isoelectric point
PaghAHKT1;5		Pop_A18G018657		535		60.02	9.41
PaghAHKT1;4		Pop_A18G034182		470		52.95	9.01
PaghGHKT1;5		Pop_G18G019156		473		52.68	9.22
PaghGHKT1;4		Pop_G18G086088		206		23.22	9.49
PalbaHKT1;5		XP_034918867.1		535		60.02	9.41
PalbaHKT1;4		XP_034906209.1		521		58.94	9.02
PapyHKT1;4		GWHPACDA010899		621		69.63	9.03
PapyHKT1;5		GWHPACDA011033		451		50.37	9.04
PtomTh1HKT1;5		GWHPBJCQ043518		535		59.98	9.33
PtomTh3HKT1;5		GWHPBJCQ045429		535		59.79	9.26
PtomTh3HKT1;4		GWHPBJCQ045526		501		56.69	9.16
PdelHKT1;5b		EVM0018125.1		516		58.11	9.51
PdelHKT1;4b		EVM0019360.1		238		27.38	8.64
PdelHKT1;5a		KAH8481580.1		473		52.73	9.27
PdelHKT1;4a		KAH8481435.1		166		18.90	9.24
PeupHKT1;5		GWHPAAYU005564.1		535		59.96	9.29
PeupHKT1;4b		GWHPAAYU005664.1		521		58.86	9.13
PeupHKT1;4a		GWHPAAYU005662.1		422		47.86	8.85
PsiHKT1;5	Simonii00009649-RA		535		59.94		9.39
PsiHKT1;4c	Simonii00039973-RA		521		58.81		9.15
PsiHKT1;4b	Simonii00039952-RA		521		59.00		9.13
PsiHKT1;4a	Simonii00039964-RA		498		56.32		9.07
PtomhAHKT1;5	KAG6741040.1		535		60.04		9.41
PtomhAHKT1;4	KAG6741120.1		500		56.53		9.16
PtomhDHKT1;5	KAG6740023.1		473		52.60		9.16
PtreHKT1;5	Potra2n18c32115.1		535		59.79		9.45
PtreHKT1;4b	Potra2n8c18208.1		521		59.10		9.27
PtreHKT1;4a	Potra2n18c32004.1		397		44.62		9.43
PtriHKT1;5	Potri.018G132200.1.p		535		60.09		9.45
PtriHKT1;4	Potri.018G147501.2.p		168		19.40		9.62

Identification of the HKT gene family members in Populus species and analysis of their expression patterns under salt stress

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种/品种 Species/Cultivar	单倍型 Haplotype	同源组1 OG01	同源组2 OG02	同源组3 OG03	同源组4 OG04	同源组5 OG05
银腺杨84K P. alba×P. tremula var. glandulosa clone 84K	单倍型A hapA	1	1	0	0	0
	单倍型G hapG	1	1	0	0	0
银白杨P. alba	/	0	0	2	0	0
新疆杨P. alba var. pyramidalis	/	1	1	0	0	0
三倍体毛白杨P.×tomentosa Carr. clone 741	单倍型1 hap 1	0	0	0	1	0
三倍体毛白杨P.×tomentosa Carr. clone 741	单倍型3 hap 3	0	0	2	0	0
美洲黑杨2-2 P. deltoides 2-2	/	1	1	0	0	0
美洲黑杨Ⅰ69 P. deltoides I69	/	1	1	0	0	0
胡杨P. euphratica	/	2	1	0	0	0
小叶杨P. simonii	/	3	1	0	0	0
二倍体毛白杨P. tomentosa	单倍型A hap A	1	1	0	0	0
二倍体毛白杨P. tomentosa	单倍型D hap D	0	0	0	1	0
欧洲山杨P. tremula	/	2	1	0	0	0
毛果杨P. trichocarpa	/	1	1	0	0	0
水稻Oryza sativa	/	0	0	1	3	4
总计Total	/	14	10	5	5	4

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