title: Over-expression of miR158 causes pollen abortion in Brassica campestris ssp. chinensis.
abstract: We identified and cloned the two precursors of miR158 and its target gene in Brassica campestris ssp. chinensis, which both had high relative expression in the inflorescences. Further study revealed that over-expression of miR158 caused reduced pollen varbility, which was caused by the degradation of pollen contents from the binucleate microspore stage. These results first suggest the role of miR158 in pollen development of Brassica campestris ssp. chinensis. MicroRNAs (miRNAs) play crucial roles in many important growth and development processes both in plants and animals by regulating the expression of their target genes via mRNA cleavage or translational repression. In this study, miR158, a Brassicaceae specific miRNA, was functionally characterized with regard to its role in pollen development of non-heading Chinese cabbage (Brassica campestris ssp. chinensis). Two family members of miR158 in B. campestris, namely bra-miR158a1 and bra-miR158a2, and their target gene bra027656, which encodes a pentatricopeptide repeat (PPR) containing protein, were identified. Then, qRT-PCR analysis and GUS-reporter system revealed that both bra-miR158 and its target gene had relatively high expression levels in the inflorescences. Further study revealed that over-expression of miR158 caused reduced pollen varbility and pollen germination ratio, and the degradation of pollen contents from the binucleate microspore stage was also found in those deformed pollen grains, which led to pollen shrinking and collapse in later pollen development stage. These results first shed light on the importance of miR158 in pollen development of Brassica campestris ssp. chinensis.
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Ma
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Jianxia
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Ziwei
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Tianqi
authors.initials: T
authors.lastname: Lyu
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Lab of Agrobiotechnology, Shenzhen Base, Shenzhen Research Institute, Chinese University of Hong Kong, Shenzhen, 518057, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Lab of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, 310058, China. jshcao@zju.edu.cn.
authors.forename: Jiashu
authors.initials: J
authors.lastname: Cao
mesh_terms: D001483:Base Sequence; D001937:Brassica / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018525:Germination / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity / Q000235:genetics; D030821:Plants, Genetically Modified; D011058:Pollen / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D014022:Tissue Survival
chemical_list: D035683:MicroRNAs
keywords: Brassica campestris; Expression; MicroR158; Pollen development