title: Dnd Is a Critical Specifier of Primordial Germ Cells in the Medaka Fish.
abstract: Primordial germ cell (PGC) specification occurs early in development. PGC specifiers have been identified in Drosophila, mouse, and human but remained elusive in most animals. Here we identify the RNA-binding protein Dnd as a critical PGC specifier in the medaka fish (Oryzias latipes). Dnd depletion specifically abolished PGCs, and its overexpression boosted PGCs. We established a single-cell culture procedure enabling lineage tracing in vitro. We show that individual blastomeres from cleavage embryos at the 32- and 64-cell stages are capable of PGC production in culture. Importantly, Dnd overexpression increases PGCs via increasing PGC precursors. Strikingly, dnd RNA forms prominent particles that segregate asymmetrically. Dnd concentrates in germ plasm and stabilizes germ plasm RNA. Therefore, Dnd is a critical specifier of fish PGCs and utilizes particle partition as a previously unidentified mechanism for asymmetric segregation. These findings offer insights into PGC specification and manipulation in medaka as a lower vertebrate model.
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore; Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Singapore 138669, Singapore.
authors: Ni
authors: N
authors: Hong
authors: Ministry of Education Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai 201306, China.
authors: Mingyou
authors: M
authors: Li
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
authors: Yongming
authors: Y
authors: Yuan
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
authors: Tiansu
authors: T
authors: Wang
authors: Laboratory of Molecular Reproductive Biology, School of Marine Sciences, Sun Yat-sen University, 135 Xingang West Road, Guangzhou 510275, China.
authors: Meisheng
authors: M
authors: Yi
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore.
authors: Hongyan
authors: H
authors: Xu
authors: Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A(∗)STAR), 31 Biopolis Way, Singapore 138669, Singapore.
authors: Huaqiang
authors: H
authors: Zeng
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore. Electronic address: dbssjx@nus.edu.sg.
authors: Jianxing
authors: J
authors: Song
authors: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore. Electronic address: dbshyh@nus.edu.sg.
authors: Yunhan
authors: Y
authors: Hong
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D009990:Oryzias; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029941:Fish Proteins; D016601:RNA-Binding Proteins
keywords: RNA particle; asymmetric segregation: dnd; lineage tracing; primordial germ cell; single-cell culture