Dynactin and Num1 cooperate to establish the cortical anchoring of cytoplasmic dynein in S. pombe.
Chromosome movement during meiosis is crucial for homologous pairing and meiotic recombination. During meiotic prophase in fission yeast, rapid nuclear migration is dependent on cytoplasmic dynein, which is anchored to the cell cortex and pulls microtubules, thereby driving nuclear migration. However, the precise mechanisms underlying dynein localization and activation remain unclear. Here, we identified three subunits of dynactin in fission yeast: Arp1, Mug5 and Jnm1 (also known as Mug1). These subunits transiently colocalized with dynein foci at the cell cortex and were essential for the cortical anchoring of dynein. Cortical factor Num1 (also known as Mcp5), which was also required for dynein anchoring, bound to dynein independently of dynactin. Whereas Num1 suppressed the sliding of dynein foci along the cortex, Arp1, Mug5 and Jnm1 were involved in the regulation of shrinkage and bundling of microtubules. From these data, we propose that dynein anchoring is established by cooperation of transient assembly of dynactin and function of Num1 at the cell cortex.
Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan Laboratory for Cell Asymmetry, RIKEN Center for Developmental Biology, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan.
Ikumi
I
Fujita
Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan Laboratory of Cell Responses, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, Aichi 444-8585, Japan Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Nishigonaka 38, Myodaiji, Okazaki, Aichi 444-8585, Japan ymst@nibb.ac.jp.
Akira
A
Yamashita
Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan Laboratory of Cell Responses, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, Aichi 444-8585, Japan Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Nishigonaka 38, Myodaiji, Okazaki, Aichi 444-8585, Japan.
Masayuki
M
Yamamoto
D002352:Carrier Proteins / Q000378:metabolism*; D056445:Cytoplasmic Dyneins / Q000378:metabolism*; D000072159:Dynactin Complex; D008540:Meiosis; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis; D012568:Schizosaccharomyces / Q000166:cytology* / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*
D002352:Carrier Proteins; D000072159:Dynactin Complex; C514938:Mcp5 protein, S pombe; D008869:Microtubule-Associated Proteins; D029702:Schizosaccharomyces pombe Proteins; D056445:Cytoplasmic Dyneins
Cytoplasmic dynein; Dynactin; Fission yeast; Horse‐tail movement; Microtubules