Transcription factor. Interacts specifically with the W box (5'-(T)TGAC[CT]-3'), a frequently occurring elicitor-responsive cis-acting element (By similarity). Modulates phosphate homeostasis and Pi translocation by regulating PHO1 expression (PubMed:25733771). Degraded through the 26S proteasome pathway during Pi starvation (PubMed:25733771).