ArticleProceedings of the National Academy of Sciences of the United States of America2014
SPX1 is a phosphate-dependent inhibitor of Phosphate Starvation Response 1 in Arabidopsis.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 238 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
238 citing papers in PubMed, 487 citations in OpenAlex.
- Arabidopsis inositol polyphosphate kinase activities regulate COP9 deneddylation functions in phosphate homeostasis.Journal of integrative plant biology · 2026Article
- SlMED25-SlPHR3-SlSPX2 module fine-tunes SlPHR3-mediated transcriptional activation of phosphate starvation response in tomato.Journal of integrative plant biology · 2026Article
- Article
- A ubiquitin carboxyl-terminal hydrolase facilitates H2A.Z removal in response to phosphate starvation.Nature communications · 2026Article
- Comparative Secretome Profiling ofPlants (Basel, Switzerland) · 2026Article
- CsSPX-PHR/PHL-PHT1 and CsmiR399a-PHO2-PHT1/PHO1 Modules Orchestrate Pi Use Efficiency and Aluminium Tolerance in Tea Plants.Plant, cell & environment · 2026Article
- Review
- Plant-Microbe Interactions in Sorghum Nutrient Acquisition: Roles of Rhizosphere Microbes and N, P, and K Transporters.Plants (Basel, Switzerland) · 2026Review
- The transcription factor PdePHR1 increases phosphorus accumulation in poplar shoot and promotes root growth.BMC plant biology · 2026Article
- Identification of Salt-Tolerant Germplasm and Salt-Responsive Genes inAntioxidants (Basel, Switzerland) · 2026Article
- Co-expression analysis identifies organ-specific gene regulatory networks responsive to phosphate limitation in hemp (Cannabis sativa L.).BMC plant biology · 2026Article
- Soil to Cytoplasm: The Mycorrhizal Phosphorus Express and Its Regulatory Steps.Journal of fungi (Basel, Switzerland) · 2026Review
- Article
- The SPX protein family in plants: from phosphate sensors to multifunctional signaling hubs.Stress biology · 2026Review
- Protein engineering fixes a major crop trade-off.Nature · 2026Article
- PHR1 mediates rapid high light responses and acclimation to high photosynthetic activity.The Plant journal : for cell and molecular biology · 2026Article
- Phosphate Acquisition in Protozoan Parasites: Transport Systems, and Extracellular Phosphate-Releasing Enzymatic Activities.International journal of molecular sciences · 2026Review
- The Medicago SPX1/3-PHR2 network relays phosphate signaling to orchestrate root nodulation-dependent nitrogen acquisition by controlling flavonoid biosynthesis.Plant communications · 2026Article
- Unfolding of RNA secondary structure impairs RNA stability to fine-tune phosphate starvation responses in rice roots.Plant communications · 2026Article
- PPSR1 Protein Functions as an Important Regulator to Enhance Plant Growth Performance Under N, P, and K Deficient Stress Conditions.Plant biotechnology journal · 2026Article
178 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
14 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
To cope with growth in low-phosphate (Pi) soils, plants have evolved adaptive responses that involve both developmental and metabolic changes. Phosphate Starvation Response 1 (PHR1) and related transcription factors play a central role in the control of Pi starvation responses (PSRs). How Pi levels control PHR1 activity, and thus PSRs, remains to be elucidated. Here, we identify a direct Pi-dependent inhibitor of PHR1 in Arabidopsis, SPX1, a nuclear protein that shares the SPX domain with yeast Pi sensors and with several Pi starvation signaling proteins from plants. Double mutation of SPX1 and of a related gene, SPX2, resulted in molecular and physiological changes indicative of increased PHR1 activity in plants grown in Pi-sufficient conditions or after Pi refeeding of Pi-starved plants but had only a limited effect on PHR1 activity in Pi-starved plants. These data indicate that SPX1 and SPX2 have a cellular Pi-dependent inhibitory effect on PHR1. Coimmunoprecipitation assays showed that the SPX1/PHR1 interaction in planta is highly Pi-dependent. DNA-binding and pull-down assays with bacterially expressed, affinity-purified tagged SPX1 and ΔPHR1 proteins showed that SPX1 is a competitive inhibitor of PHR1 binding to its recognition sequence, and that its efficiency is highly dependent on the presence of Pi or phosphite, a nonmetabolizable Pi analog that can repress PSRs. The relative strength of the SPX1/PHR1 interaction is thus directly influenced by Pi, providing a link between Pi perception and signaling.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.