3.A.1.204.8
The epidermal plasma membrane cuticular lipid (wax) exporters, ABCG11/ABCG11 and ABCG11/ABCG12; ABCG11 is also called Wbc11; Desperado (DSO); COF1; PEL1. ABCG12 is also called CER5, WBC12 and D3 (Panikashvili and Aharoni 2008).  Required for the cuticle and pollen coat development by controlling cutin and possibly wax transport to the extracellular matrix. Involved in developmental plasticity and stress responses (Bird et al. 2007).  ABCG11 can traffic to the plasma membrane in the absence of ABCG12 and can form flexible dimers. By contrast, ABCG12 was retained in the endoplasmic reticulum in the absence of ABCG11, indicating that ABCG12 can only form dimers with ABCG11 in the plasma membrane of epidermal cells. Some ABCG proteins may be promiscuous, having multiple partnerships, while others may form obligate heterodimers for specialized functions (McFarlane et al. 2010). Othere designations include: White-brown complex homolog protein 11, AtWBC11, of 703 aas with 6 TMSs (C-terminal) in a 5 + 1 TMS arrangement.  It is involved in cuticle development and prevention of organ fusion (Luo et al. 2007).  AbcG transporters are required for export of diverse cuticular lipids (McFarlane et al. 2010).  It is required for cuticle, root suberin and pollen coat development by controlling cutin and maybe wax transport to the extracellular matrix (Le Hir et al. 2013). It is also involved in developmental plasticity and stress responses. Together with ABCG9 and ABCG14, it is required for vascular development by regulating lipid/sterol homeostasis (Le Hir et al. 2013), and may be a transporter of lignin precursors during tracheary element differentiation (Takeuchi et al. 2018). It is expressed in seedlings, roots, stems, leaves, flowers, and siliques, mostly in epidermis, trichomes, vasculatures and developing tissues (Le Hir et al. 2013).