ATP-binding RNA helicase involved in pre-mRNA splicing. Required for the export of mRNA out of the nucleus (By similarity). Required for tapetal programmed cell death (PCD) and degeneration during anther development. Forms dimer with AIP2 and binds the promoter region of the cysteine protease CP1. Can complement the yeast RNA helicase SUB2. Plants silencing AIP1 and AIP2 are male sterile (PubMed:21467577). ATP + H2O = ADP + H(+) + phosphate Homodimer and heterodimer with AIP2 (PubMed:21467577). Interacts with API5 (PubMed:21467577). The Q motif is unique to and characteristic of the DEAD box family of RNA helicases and controls ATP binding and hydrolysis. Belongs to the DEAD box helicase family. DECD subfamily. Extended N-terminus.