RRC ID 69991
Author Wang ZF, Mi TW, Gao YQ, Feng HQ, Wu WH, Wang Y.
Title STOP1 Regulates LKS1 Transcription and Coordinates K+/NH4+ Balance in Arabidopsis Response to Low-K+ Stress.
Journal Int J Mol Sci
Abstract Potassium and nitrogen are essential mineral elements for plant growth and development. The protein kinase LKS1/CIPK23 is involved in both K+ and NH4+ uptake in Arabidopsis root. The transcripts of LKS1 can be induced by low K+ (0.1 mM) and high NH4+ (30 mM); however, the molecular mechanism is still unknown. In this study, we isolated the transcription factor STOP1 that positively regulates LKS1 transcription in Arabidopsis responses to both low-K+ and high-NH4+ stresses. STOP1 proteins can directly bind to the LKS1 promoter, promoting its transcription. The stop1 mutants displayed a leaf chlorosis phenotype similar to lks1 mutant when grown on low-K+ and high-NH4+ medium. On the other hand, STOP1 overexpressing plants exhibited a similar tolerant phenotype to LKS1 overexpressing plants. The transcript level of STOP1 was only upregulated by low K+ rather than high NH4+; however, the accumulation of STOP1 protein in the nucleus was required for the upregulation of LKS1 transcripts in both low-K+ and high-NH4+ responses. Our data demonstrate that STOP1 positively regulates LKS1 transcription under low-K+ and high-NH4+ conditions; therefore, LKS1 promotes K+ uptake and inhibits NH4+ uptake. The STOP1/LKS1 pathway plays crucial roles in K+ and NH4+ homeostasis, which coordinates potassium and nitrogen balance in plants in response to external fluctuating nutrient levels.
Volume 23(1)
Published 2021-12-29
DOI 10.3390/ijms23010383
PII ijms23010383
PMID 35008809
PMC PMC8745191
MeSH Ammonium Compounds / metabolism* Arabidopsis / drug effects Arabidopsis / genetics* Arabidopsis / physiology* Arabidopsis Proteins / genetics* Arabidopsis Proteins / metabolism Base Sequence Gene Expression Regulation, Plant Genes, Plant Models, Biological Mutation / genetics Plant Roots / metabolism Potassium / metabolism* Potassium / pharmacology Promoter Regions, Genetic / genetics Protein Binding / drug effects Protoplasts / drug effects Protoplasts / metabolism Stress, Physiological* / drug effects Stress, Physiological* / genetics Transcription Factors / metabolism* Transcription, Genetic* / drug effects
IF 4.556
Arabidopsis / Cultured plant cells, genes psi00011 psi00012