The AlHAK1 gene encoding a high-affinity K+ transporter was isolated from Aeluropus littoralis (Gouan) Parl, a graminaceous halophyte, and plays a crucial role in nutrition and ion homeostasis in plant cell. To investigate the regulation role of AlHAK1 on the transcriptional level, an about 1.3 kb 5'-flanking region of the AlHAK1 gene containing a putative promoter was cloned by genome walking method. Cis-regulatory elements analysis showed AlHAK1-promoter region contained typical TATA and CAAT boxes, and some growth and development relative motifs, as well as environmental responsive elements. To reveal the function and regulating role, the Al-HAK1 promoter was fused to the β-glucuronidase (GUS) reporter gene in the pCAMBIA1301 vector and introduced into rice via Agrobacterium-mediated transformation. Histochemical staining indicated that the GUS expression directed by AlHAK1 promoter was observed in leaves, stems, roots, anther, lemma, and palea. GUS quantitative fluorometric analysis indicated that GUS activity directed by AlHAK1 promoter was lower than CaMV35S and Ubiquitin constitutive promoters; however, in the roots and stems the GUS activity was relatively high and displayed a tissue-specific expression pattern. Under ABA, high temperature or drought stress, the GUS activity directed by AlHAK1 promoter was inducible in the roots and stems, suggesting the elements of HSE (-682 bp) and MybBS (-1 268 bp) might play a role in the inducible regulation.
ZHANG Gao-Hua, WANG He, WANG Xu-Da, FENG Ming, LI Huai-Mei, LI Shu-Ying
. Isolation of the promoter region of HAK gene from Aeluropus littoralis and functional analysis in rice[J]. Hereditas(Beijing), 2012
, 34(6)
: 742
-748
.
DOI: 10.3724/SP.J.1005.2012.00742
[1] Mäser P, Thomine S, Schroeder JI, Ward JM, Hirschi K, Sze H, Talke IN, Amtmann A, Maathuis FJ, Sanders D, Harper JF, Tchieu J, Gribskov M, Persans MW, Salt DE, Kim SA, Guerinot ML. Phylogenetic relationships within cation transporter families of Arabidopsis. Plant Physiol, 2001, 126(4): 1646-1667.
[2] Epstein E, Rains DW, Elzam OE. Resolution of dual mechanisms of potassium absorption by barley roots. Proc Natl Acad Sci USA, 1963, 49(5): 684-692.
[3] Zimmermann S, Sentenac H. Plant ion channels from molecular structures to physiological functions. Curr Opin Plant Biol, 1999, 2(6): 477-482.
[4] Ahn SJ, Shin R, Schachtman DP. Expression of KT/KUP genes in Arabidopsis and the role of root hairs in K+ uptake. Plant Physiol, 2004, 134(3): 1135-1145.
[5] Fu HH, Luan S. AtHUP1: a dual-affinity K+ transporter from Arabidopsis. Plant Cell, 1998, 10(1): 63-73.
[6] Spalding EP, Hirsch RE, Lewis DR, Qi Z, Sussman MR, Lewis BD. Potassium uptake supporting plant growth in the absence of AKT1 channel activity: inhibition by am-monium and stimulation by sodium. J Gen Physiol, 1999, 113(6): 909-918.
[7] Alemán F, Nieves-Cordones M, Martínez V, Rubio F. Root K+ acquisition in plants: the Arabidopsis thaliana model. Plant Cell Physiol, 2011, 52(9): 1603-1612.
[8] Rodríguez-Navarro A, Rubio F. High-affinity potassium and sodium transport systems in plants. J Exp Bot, 2006, 57(5): 1149-1160.
[9] Santa-María GE, Rubio F, Dubcovsky J, Rodríguez-Navarro A. The HAK1 gene of barley is a member of a large gene family and encodes a high-affinity potassium transporter. Plant Cell, 1997, 9(12): 2281-2289.
[10] Kim EJ, Kwak JM, Uozumi N, Schroeder JI. AtKUP1: an Arabidopsis gene encoding high- affinity potassium transport activity. Plant Cell, 1998, 10(1): 51-62.
[11] Su H, Golldack D, Zhao CS, Bohnert HJ. The expression of HAK-type K+ transporters is regulated in response to salinity stress in common ice plant. Plant Physiol, 2002, 129(4): 1482-1493.
[12] Bañuelos MA, Garciadeblas B, Cubero B, Rodríguez-Navarro A. Inventory and functional characterization of the HAK potassium transporters of rice. Plant Physiol, 2002, 130(2): 784-795.
[13] Chinnusamy V, Jagendorf A, Zhu JK. Understanding and improving salt tolerance in plants. Crop Sci, 2005, 45(2): 437-448.
[14] Zhu JK. Regulation of ion homeostasis under salt stress. Curr Opin Plant Biol, 2003, 6(5): 441-445.
[15] 化党领, 介晓磊, 韩锦锋, 谭金芳, 郭天财. 植物钾吸收的分子水平研究. 植物营养与肥料学报, 2002, 8(3): 377-383.
[16] 刘志华, 赵可夫. 盐胁迫对獐茅生长及Na+和K+含量的影响. 植物生理与分子生物学学报, 2005, 31 (3): 311-316.
[17] Barhoumi Z, Djebali W, Smaoui A, Chaïbi W, Abdelly C. Contribution of NaCl excretion to salt resistance of Aeluropus littoralis (Willd) Parl. J Plant Physiol, 2007, 164(7): 842-850.
[18] Su Q, Feng SY, An LJ, Zhang GH. Cloning and functional expression in Saccharomyces cereviae of a K+ transporter, AlHAK, from the graminaceous halophyte, Aeluropus littoralis. Biotechnol Lett, 2007, 29(12): 1959-1963.
[19] Toki S, Hara N, Ono K, Onodera H, Tagiri A, Oka S, Tanaka H. Early infection of scutellum tissue with Agrobacterium allows high-speed transformation of rice. Plant J, 2006, 47(6): 969-976.
[20] Jefferson RA, Burgess SM, Hirsh D. β-glucuronidase from Escherichia coli as a gene-fusion marker. Proc Natl Acad Sci USA, 1986, 83(22): 8447-8451.
[21] Shinozaki K, Yamaguchi-Shinozaki K, Seki M. Regulatory network of gene expression in the drought and cold stress responses. Curr Opin Plant Biol, 2003, 6(5): 410-417.
[22] Rubio F, Santa-Maria GE, Rodríguez-Navarro A. Cloning of Arabidopsis and barley cDNAs encoding HAK potassium transporters in root and shoot ce
