title: An ABC transporter, OsABCG26, is required for anther cuticle and pollen exine formation and pollen-pistil interactions in rice.
abstract: Wax, cutin and sporopollenin are essential components for the formation of the anther cuticle and the pollen exine, respectively. Their lipid precursors are synthesized by secretory tapetal cells and transported to the anther and microspore surface for deposition. However, the molecular mechanisms involved in the formation of the anther cuticle and pollen exine are poorly understood in rice. Here, we characterized a rice male sterile mutant osabcg26. Molecular cloning and sequence analysis revealed a point mutation in the gene encoding an ATP binding cassette transporter G26 (OsABCG26). OsABCG26 was specifically expressed in the anther and pistil. Cytological analysis revealed defects in tapetal cells, lipidic Ubisch bodies, pollen exine, and anther cuticle in the osabcg26 mutant. Expression of some key genes involved in lipid metabolism and transport, such as UDT1, WDA1, CYP704B2, OsABCG15, OsC4 and OsC6, was significantly altered in osabcg26 anther, possibly due to a disturbance in the homeostasis of anther lipid metabolism and transport. Additionally, wild-type pollen tubes showed a growth defect in osabcg26 pistils, leading to low seed setting in osabcg26 cross-pollinated with the wild-type pollen. These results indicated that OsABCG26 plays an important role in anther cuticle and pollen exine formation and pollen-pistil interactions in rice.
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China; Guangdong Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631, China.
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Chang
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China.
authors.forename: Zhufeng
authors.initials: Z
authors.lastname: Chen
authors.affiliation: School of Life Sciences, Capital Normal University, Beijing 100048, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yan
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Xie
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Lu
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China.
authors.forename: Na
authors.initials: N
authors.lastname: Wang
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China.
authors.forename: Qiqing
authors.initials: Q
authors.lastname: Lu
authors.affiliation: School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning 530005, China.
authors.forename: Guangzhe
authors.initials: G
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning 530005, China. Electronic address: xiajx@gxu.edu.cn.
authors.forename: Jixing
authors.initials: J
authors.lastname: Xia
authors.affiliation: Shenzhen Institute of Molecular Crop Design, Shenzhen 518107, China; Guangdong Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631, China. Electronic address: txy@frontier-ag.com.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Tang
mesh_terms: D000070996:ATP Binding Cassette Transporter, Subfamily G / Q000502:physiology*; D000595:Amino Acid Sequence; D035264:Flowers / Q000648:ultrastructure; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000502:physiology* / Q000648:ultrastructure; D051479:Plant Infertility / Q000235:genetics; D010940:Plant Proteins / Q000502:physiology; D053205:Pollen Tube / Q000502:physiology*
chemical_list: D000070996:ATP Binding Cassette Transporter, Subfamily G; D010940:Plant Proteins
keywords: ABC transporter; Anther cuticle; Male sterility; Pollen exine; Pollen tube growth