HIM-8 binds to the X chromosome pairing center and mediates chromosome-specific meiotic synapsis.
The him-8 gene is essential for proper meiotic segregation of the X chromosomes in C. elegans. Here we show that loss of him-8 function causes profound X chromosome-specific defects in homolog pairing and synapsis. him-8 encodes a C2H2 zinc-finger protein that is expressed during meiosis and concentrates at a site on the X chromosome known as the meiotic pairing center (PC). A role for HIM-8 in PC function is supported by genetic interactions between PC lesions and him-8 mutations. HIM-8 bound chromosome sites associate with the nuclear envelope (NE) throughout meiotic prophase. Surprisingly, a point mutation in him-8 that retains both chromosome binding and NE localization fails to stabilize pairing or promote synapsis. These observations indicate that stabilization of homolog pairing is an active process in which the tethering of chromosome sites to the NE may be necessary but is not sufficient.
Phillips
Carolyn M
CM
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Wong
Chihunt
C
Bhalla
Needhi
N
Carlton
Peter M
PM
Weiser
Pinky
P
Meneely
Philip M
PM
Dernburg
Abby F
AF
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D023902:Chromosome Pairing / Q000235:genetics / Q000502:physiology*; D012734:Disorders of Sex Development / Q000235:genetics; D005260:Female; D017404:In Situ Hybridization, Fluorescence; D034882:Lamins / Q000032:analysis; D008297:Male; D008540:Meiosis / Q000235:genetics / Q000502:physiology*; D049469:Meiotic Prophase I / Q000235:genetics; D008856:Microscopy, Fluorescence; D009154:Mutation / Q000235:genetics; D009685:Nuclear Envelope / Q000737:chemistry / Q000502:physiology; D049471:Pachytene Stage / Q000235:genetics; D010641:Phenotype; D017354:Point Mutation / Q000235:genetics; D013573:Synaptonemal Complex / Q000235:genetics / Q000378:metabolism; D014960:X Chromosome / Q000235:genetics / Q000378:metabolism*; D016335:Zinc Fingers / Q000235:genetics
D029742:Caenorhabditis elegans Proteins; D018797:Cell Cycle Proteins; C507738:HIM-8 protein, C elegans; D034882:Lamins