title: Identification of small RNAs in late developmental stage of rice anthers.
abstract: Small RNAs including microRNA (miRNA) and small interfering RNA (siRNA) are known as repressors of gene expression. There are many plant proteins involved in small RNA-mediated gene silencing, such as Dicer ribonucleases and RNA-dependent RNA polymerases. However, most of these proteins have been reported to be absent in the late developmental stage of the plant male gamete, pollen. In order to clarify the existence of the small RNAs during maturation of pollen, we cloned and sequenced small RNAs from rice anthers including tricellular pollen. From fifty six candidates of small RNAs, we identified two known miRNAs (miR166 and miR167), eight potential miRNAs, and ten putative heterochromatic siRNAs (hc-siRNAs). RNA gel blot analyses clearly showed that miR166 and miR167 were accumulated in the uninuclear pollen stage of anther development and remained until the tricellular pollen stage. Our cloning and RNA gel blot analyses of small RNAs led us to propose a possible function of small RNA-mediated gene regulation for the development of male gametes in rice.
authors.affiliation: Laboratory of Plant Reproductive Genetics, Graduate School of Life Sciences, Tohoku University, Sendai, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Fujioka
authors.forename: Fumi
authors.initials: F
authors.lastname: Kaneko
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Kazama
authors.forename: Keita
authors.initials: K
authors.lastname: Suwabe
authors.forename: Go
authors.initials: G
authors.lastname: Suzuki
authors.forename: Amane
authors.initials: A
authors.lastname: Makino
authors.forename: Tadahiko
authors.initials: T
authors.lastname: Mae
authors.forename: Makoto
authors.initials: M
authors.lastname: Endo
authors.forename: Makiko
authors.initials: M
authors.lastname: Kawagishi-Kobayashi
authors.forename: Masao
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D035683:MicroRNAs / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D012275:Oryza / Q000235:genetics* / Q000254:growth & development*; D011058:Pollen / Q000235:genetics* / Q000254:growth & development; D018749:RNA, Plant / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D034741:RNA, Small Interfering / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D035683:MicroRNAs; D018749:RNA, Plant; D034741:RNA, Small Interfering