Involved in abscisic acid signal transduction. Plays a role in seed germination and early seedling development. Involved in the blue light (BL) signaling. Interacts with the G protein alpha-1 subunit GPA1. Interacts with NFYB6 and NFYB9. Present at similar levels in seedlings and mature plants. Up-regulated by abscisic acid (ABA) and low-fluence red light, but not by low-fluence blue light. Contains one cupin domain that is not required for interaction with the G protein alpha subunit. Altered response to blue light (BL) and abscisic acid (ABA). Belongs to the pirin family.