Transcription factor that possesses transactivation activity in yeast (PubMed:17604002, PubMed:21055780, PubMed:18236009). Involved in abscisic acid (ABA) signaling pathway. Binds to the G-box motif 5'-CACGTG-3' of TRAB1 gene promoter (PubMed:17604002). Involved in the regulation of pollen maturation. May act as negative regulator of salt stress response (PubMed:18236009). Together with PYL5, PP2C30 and SAPK2, is part of an ABA signaling unit that modulates seed germination and early seedling growth (PubMed:22071266). Forms homodimers. Interacts with VP1 (PubMed:17604002). Interacts with GF14D (PubMed:21055780). Interacts with PP2C51 (PubMed:28000033). Interacts with SAPK2 (PubMed:22071266, PubMed:28000033). Expressed in roots, leaves and panicles (PubMed:17604002). Expressed in seeds (PubMed:21055780). Induced by abscisic acid (ABA) (PubMed:21055780, PubMed:18236009, PubMed:22071266). Induced by salt stress. Down-regulated by cold and drought stresses (PubMed:18236009). Phosphorylated at Ser-44 by SAPK6. Plants silencing ABI5 exhibit low fertility rate due to abnormal development of mature pollen. Plants silencing ABI5 display increased tolerance to salt stress. Belongs to the bZIP family. ABI5 subfamily. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus.