Isolation and functional identification of an apple MdCER1 gene

Abstract

The outermost layer of the plant epidermis is covered by cuticular wax, which resists UV radiation, insects, and pathogens, and protects the plant from various environmental stressors. We cloned MdCER1 to further study the molecular regulatory pathway of cuticular wax in apple (Malus × domestica Borkh.). The results showed that MdCER1 is a homolog of Arabidopsis CER1, which is essential for wax synthesis. A subcellular localization study revealed that MdCER1 was localized on the endoplasmic reticulum. We examined the expression pattern of MdCER1 in different tissues and found that it was constitutively expressed in roots, stems, leaves, flowers, and fruits, with the highest expression in leaves. Ectopic expression of MdCER1 promoted the accumulation of cuticular wax by changing the permeability of the epidermis and the response to abscisic acid, as well as by improving drought resistance in Arabidopsis.