Asunder is a critical regulator of dynein-dynactin localization during Drosophila spermatogenesis.
Spermatogenesis uses mitotic and meiotic cell cycles coordinated with growth and differentiation programs to generate functional sperm. Our analysis of a Drosophila mutant has revealed that asunder (asun), which encodes a conserved protein, is an essential regulator of spermatogenesis. asun spermatocytes arrest during prophase of meiosis I. Strikingly, arrested spermatocytes contain free centrosomes that fail to stably associate with the nucleus. Spermatocytes that overcome arrest exhibit severe defects in meiotic spindle assembly, chromosome segregation, and cytokinesis. Furthermore, the centriole-derived basal body is detached from the nucleus in asun postmeiotic spermatids, resulting in abnormalities later in spermatogenesis. We find that asun spermatocytes and spermatids exhibit drastic reduction of perinuclear dynein-dynactin, a microtubule motor complex. We propose a model in which asun coordinates spermatogenesis by promoting dynein-dynactin recruitment to the nuclear surface, a poorly understood process required for nucleus-centrosome coupling at M phase entry and fidelity of meiotic divisions.
Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA.
Michael A
MA
Anderson
Jeanne N
JN
Jodoin
Ethan
E
Lee
Karen G
KG
Hales
Thomas S
TS
Hays
Laura A
LA
Lee
D000818:Animals; D030801:Animals, Genetically Modified; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism; D020090:Chromosome Segregation; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism*; D000072159:Dynactin Complex; D004398:Dyneins / Q000378:metabolism*; D005298:Fertility / Q000235:genetics / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D007248:Infertility, Male / Q000235:genetics / Q000503:physiopathology; D008297:Male; D008540:Meiosis / Q000235:genetics; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D009154:Mutation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013087:Spermatids / Q000378:metabolism / Q000473:pathology; D013090:Spermatocytes / Q000378:metabolism / Q000473:pathology; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology*; D008941:Spindle Apparatus / Q000378:metabolism; D014162:Transfection
D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; C544294:asun protein, Drosophila; D049452:Green Fluorescent Proteins; D004398:Dyneins