Figure 6.

Surface lipids are secreted by ABC transporters of the ABCG family.

(A) Loss-of-function mutants in AtABCG26 fail to self-pollinate due to defective pollen development caused by impaired sporopollenin formation. Scale bars = 100 µm. Figure taken from Choi et al. (2011).

(B) Members of the ABCG family that participate in cuticle formation by transporting components of the cuticular wax and/or cutin. See text for details.

(C) AtABCG26 is involved in pollen exine formation, possibly by transporting exine precursors from the tapetum to the locules.