Species	Reference gene ID	Possible function	Papers / DOI
Arabidopsis	At2g26660	May inhibit PHR1 DNA-binding activity in a Pi-dependent manner.	SPX1 is a phosphate-dependent inhibitor of Phosphate Starvation Response 1 in Arabidopsis.; 2014; DOI: 10.1073/pnas.1404654111; PMID: 25271326; https://pubmed.ncbi.nlm.nih.gov/25271326/
Arabidopsis	At5g20150	Plays a positive role in plant adaptation to phosphate starvation.	Characterization of a sub-family of Arabidopsis genes with the SPX domain reveals their diverse functions in plant tolerance to phosphorus starvation.; 2008; DOI: 10.1111/j.1365-313x.2008.03460.x; PMID: 18315545; https://pubmed.ncbi.nlm.nih.gov/18315545/ | SPX1 is a phosphate-dependent inhibitor of Phosphate Starvation Response 1 in Arabidopsis.; 2014; DOI: 10.1073/pnas.1404654111; PMID: 25271326; https://pubmed.ncbi.nlm.nih.gov/25271326/
Rice	Os06g0603600	Involved in plant adaptation to phosphate (Pi) starvation.	Involvement of OsSPX1 in phosphate homeostasis in rice.; 2009; DOI: 10.1111/j.1365-313x.2008.03734.x; PMID: 19000161; https://pubmed.ncbi.nlm.nih.gov/19000161/ | Regulation of OsSPX1 and OsSPX3 on expression of OsSPX domain genes and Pi-starvation signaling in rice.; 2009; DOI: 10.1111/j.1744-7909.2009.00834.x; PMID: 19566645; https://pubmed.ncbi.nlm.nih.gov/19566645/ | OsSPX1 suppresses the function of OsPHR2 in the regulation of expression of OsPT2 and phosphate homeostasis in shoots of rice.; 2010; DOI: 10.1111/j.1365-313x.2010.04170.x; PMID: 20149131; https://pubmed.ncbi.nlm.nih.gov/20149131/ | Rice SPX1 and SPX2 inhibit phosphate starvation responses through interacting with PHR2 in a phosphate-dependent manner.; 2014; DOI: 10.1073/pnas.1404680111; PMID: 25271318; https://pubmed.ncbi.nlm.nih.gov/25271318/ | An SPX-RLI1 Module Regulates Leaf Inclination in Response to Phosphate Availability in Rice.; 2018; DOI: 10.1105/tpc.17.00738; PMID: 29610209; https://pubmed.ncbi.nlm.nih.gov/29610209/
Rice	UniProt: B8B4D0	Involved in plant adaptation to phosphate (Pi) starvation (By similarity).	No verified direct reference in this release
Rice	Os02g0202200	Inhibits PHR2 DNA-binding activity via a phosphate (Pi)- dependent protein interaction.	Rice SPX1 and SPX2 inhibit phosphate starvation responses through interacting with PHR2 in a phosphate-dependent manner.; 2014; DOI: 10.1073/pnas.1404680111; PMID: 25271318; https://pubmed.ncbi.nlm.nih.gov/25271318/ | An SPX-RLI1 Module Regulates Leaf Inclination in Response to Phosphate Availability in Rice.; 2018; DOI: 10.1105/tpc.17.00738; PMID: 29610209; https://pubmed.ncbi.nlm.nih.gov/29610209/