Aldehyde decarbonylase involved in the conversion of aldehydes to alkanes (PubMed:17138699). Core component of a very-long-chain alkane synthesis complex (By similarity). Required for the biosynthesis of very-long-chain fatty acids (including polyesters) in cuticles, anther tapetum and pollen exine (PubMed:17138699). a long-chain fatty aldehyde + H(+) + 2 NADPH + O2 = a long-chain alkane + formate + H2O + 2 NADP(+) Homodimer. Expressed in panicles, developing spikelets, stamens and hulls and, at low levels, in roots, developing seeds, flag leaves and seedling shoots (PubMed:19322663, PubMed:17138699). Strongly expressed in the epidermal cells of anthers (PubMed:17138699). In developing spikelets, expressed in all floral organs from the premeiosis stage to the heading stage. Also present in the outer and inner epidermis and trichomes of the palea/lemma, lodicules, stigmas, and anthers. In anthers at the vacuolated pollen stage, expressed strongly in the epidermis but only weakly in the tapetum, endothecium, and connective tissue. In vegetative tissue, confinde to collar regions (between the leaf sheath and the leaf blade) and the base of shoots. Induced by salt stress and abscisic acid (ABA). Male-sterile plants characterized by small and white anthers lacking mature pollen grains. Defects in the biosynthesis of very-long-chain fatty acids (including polyesters) in cuticles and in the innermost layer of the anther wall (the tapetum). Lack of epicuticular wax crystals in the outer layer of the anther and severely retarded microspore development and finally disrupted as a result of defective pollen exine formation. Belongs to the sterol desaturase family.