title: A Drosophila orthologue of larp protein family is required for multiple processes in male meiosis.
abstract: It is important for the proper execution of cell division in both mitosis and meiosis that the chromosome segregation, cytokinesis, and partition of cell organelles progress in smooth coordination. We show here that the mitochondria inheritance is closely linked with microtubules during meiotic divisions in Drosophila males. They are first clustered in a cell equator at metaphase associated with astral microtubules and then distributed along central spindle microtubules after anaphase. The molecular mechanism for the microtubule-dependent inheritance of mitochondria in male meiosis has not been demonstrated yet. We first isolated mutations for a larp gene that is highly conserved among eukaryotes and showed that these mutant males exhibited multiple meiotic phenotypes such as a failure of chromosome segregation, cytokinesis, and mitochondrial partition. Our cytological examination revealed that the mutants showed defects in spindle pole organization and spindle formation. The larp encodes a Drosophila orthologue of a La-related protein containing a domain exhibiting an outstanding homology with a La type RNA-binding protein. Surprisingly, the dLarp protein is localized in the cytoplasm of the male germ line cells, as observed by its distinct co-localization with mitochondria in early spermatocytes and during meiotic divisions. We discuss here the essential role that dLarp plays in multiple processes in Drosophila male meiosis.
authors.affiliation: Drosophila Genetic Resource Center, Kyoto Institute of Technology, Kyoto, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Ichihara
authors.forename: Hanako
authors.initials: H
authors.lastname: Shimizu
authors.forename: Osamu
authors.initials: O
authors.lastname: Taguchi
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: Yoshihiro H
authors.initials: YH
authors.lastname: Inoue
mesh_terms: D000818:Animals; D018385:Centrosome / Q000502:physiology; D002842:Chromatids / Q000502:physiology; D020090:Chromosome Segregation; D048749:Cytokinesis; D004330:Drosophila / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics* / Q000502:physiology*; D008297:Male; D008540:Meiosis / Q000235:genetics; D008870:Microtubules / Q000502:physiology / Q000648:ultrastructure; D008928:Mitochondria / Q000235:genetics / Q000502:physiology; D050505:Mutant Proteins / Q000502:physiology; D009154:Mutation; D013090:Spermatocytes / Q000166:cytology / Q000502:physiology*; D008941:Spindle Apparatus / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics* / Q000502:physiology*
chemical_list: D029721:Drosophila Proteins; C485865:Larp protein, Drosophila; D050505:Mutant Proteins; D014157:Transcription Factors