title: Analysis of SDF-1/CXCR4 signaling in primordial germ cell migration and survival or differentiation in Xenopus laevis.
abstract: Directional migration of primordial germ cells (PGCs) toward future gonads is a common feature in many animals. In zebrafish, mouse and chicken, SDF-1/CXCR4 chemokine signaling has been shown to have an important role in PGC migration. In Xenopus, SDF-1 is expressed in several regions in embryos including dorsal mesoderm, the target region that PGCs migrate to. CXCR4 is known to be expressed in PGCs. This relationship is consistent with that of more well-known animals. Here, we present experiments that examine whether chemokine signaling is involved in PGC migration of Xenopus. We investigate: (1) Whether injection of antisense morpholino oligos (MOs) for CXCR4 mRNA into vegetal blastomere containing the germ plasm or the precursor of PGCs disturbs the migration of PGCs? (2) Whether injection of exogenous CXCR4 mRNA together with MOs can restore the knockdown phenotype? (3) Whether the migratory behavior of PGCs is disturbed by the specific expression of mutant CXCR4 mRNA or SDF-1 mRNA in PGCs? We find that the knockdown of CXCR4 or the expression of mutant CXCR4 in PGCs leads to a decrease in the PGC number of the genital ridges, and that the ectopic expression of SDF-1 in PGCs leads to a decrease in the PGC number of the genital ridges and an increase in the ectopic PGC number. These results suggest that SDF-1/CXCR4 chemokine signaling is involved in the migration and survival or in the differentiation of PGCs in Xenopus.
authors.affiliation: Department of Biological Function, Faculty of Science, Osaka City University, Sumiyoshi, Osaka, Japan.
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Tanigawa
authors.forename: Ryohei
authors.initials: R
authors.lastname: Minamide
authors.forename: Kohji
authors.initials: K
authors.lastname: Ikenishi
authors.forename: Tohru
authors.initials: T
authors.lastname: Komiya
mesh_terms: D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D002465:Cell Movement; D002470:Cell Survival; D054377:Chemokine CXCL12 / Q000378:metabolism*; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D005854:Germ Cells / Q000166:cytology*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D012333:RNA, Messenger / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism*; D015398:Signal Transduction; D029867:Xenopus Proteins / Q000378:metabolism*; D014982:Xenopus laevis / Q000196:embryology*
chemical_list: C449185:CXCL12 protein, Xenopus; D054377:Chemokine CXCL12; D012333:RNA, Messenger; D019718:Receptors, CXCR4; D029867:Xenopus Proteins