title: HPS4/SABRE regulates plant responses to phosphate starvation through antagonistic interaction with ethylene signalling.
abstract: The phytohormone ethylene plays important roles in regulating plant responses to phosphate (Pi) starvation. To date, however, no molecular components have been identified that interact with ethylene signalling in regulating such responses. In this work, an Arabidopsis mutant, hps4, was characterized that exhibits enhanced responses to Pi starvation, including increased inhibition of primary root growth, enhanced expression of Pi starvation-induced genes, and overproduction of root-associated acid phosphatases. Molecular cloning indicated that hps4 is a new allele of SABRE, which was previously identified as an important regulator of cell expansion in Arabidopsis. HPS4/SABRE antagonistically interacts with ethylene signalling to regulate plant responses to Pi starvation. Furthermore, it is shown that Pi-starved hps4 mutants accumulate more auxin in their root tips than the wild type, which may explain the increased inhibition of their primary root growth when grown under Pi deficiency.
authors.affiliation: MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing, 100084, PR China.
authors.forename: Hailan
authors.initials: H
authors.lastname: Yu
authors.forename: Nan
authors.initials: N
authors.lastname: Luo
authors.forename: Lichao
authors.initials: L
authors.lastname: Sun
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
mesh_terms: D000135:Acid Phosphatase / Q000235:genetics / Q000378:metabolism; D000483:Alleles; D000872:Anthocyanins / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002874:Chromosome Mapping; D005030:Ethylenes / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology*; D007210:Indoleacetic Acids / Q000032:analysis / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D018519:Meristem / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D009154:Mutation; D009928:Organ Specificity; D010710:Phosphates / Q000172:deficiency* / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological / Q000502:physiology
chemical_list: D000872:Anthocyanins; D029681:Arabidopsis Proteins; D005030:Ethylenes; C579713:HPS4 protein, Arabidopsis; D007210:Indoleacetic Acids; D047908:Intracellular Signaling Peptides and Proteins; D010710:Phosphates; D010937:Plant Growth Regulators; C030737:indoleacetic acid; C036216:ethylene; D000135:Acid Phosphatase