title: MEI-1/MEI-2 katanin-like microtubule severing activity is required for Caenorhabditis elegans meiosis.
abstract: The Caenorhabditis elegans meiotic spindle is morphologically distinct from the first mitotic spindle, yet both structures form in the same cytoplasm approximately 20 minutes apart. The mei-1 and mei-2 genes of C. elegans are required for the establishment of the oocyte meiotic spindle but are not required for mitotic spindle function. mei-1 encodes an AAA ATPase family member with similarity to the p60 catalytic subunit of the heterodimeric sea urchin microtubule-severing protein, katanin. We report that mei-2 encodes a 280-amino acid protein containing a region similar to the p80-targeting subunit of katanin. MEI-1 and MEI-2 antibodies decorate the polar ends of meiotic spindle microtubules and meiotic chromatin. We find that the subcellular location of MEI-2 depends on wild-type mei-1 activity and vice versa. These experiments, combined with MEI-1 and MEI-2's similarity to p60 and p80 katanin, suggest that the C. elegans proteins function as a complex. In support of this idea, MEI-1 and MEI-2 physically associate in HeLa cells. Furthermore, co-expression of MEI-1 and MEI-2 in HeLa cells results in the disassembly of microtubules. These data lead us to conclude that MEI-1/MEI-2 microtubule-severing activity is required for meiotic spindle organization in C. elegans.
authors.affiliation: Department of Biochemistry, Development Research Group, University of Calgary, Calgary, Alberta, T2N 4N1 Canada.
authors.forename: M
authors.initials: M
authors.lastname: Srayko
authors.forename: D W
authors.initials: DW
authors.lastname: Buster
authors.forename: O A
authors.initials: OA
authors.lastname: Bazirgan
authors.forename: F J
authors.initials: FJ
authors.lastname: McNally
authors.forename: P E
authors.initials: PE
authors.lastname: Mains
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins; D003001:Cloning, Molecular; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D006367:HeLa Cells; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D000074201:Katanin; D008540:Meiosis / Q000235:genetics*; D008969:Molecular Sequence Data; D009865:Oocytes / Q000166:cytology* / Q000502:physiology; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014162:Transfection
chemical_list: D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; D011994:Recombinant Proteins; D000251:Adenosine Triphosphatases; C086678:MEI-1 protein, C elegans; C409220:MEI-2 protein, C elegans; D000074201:Katanin