The enigmatic meiotic dense body and its newly discovered component, SCML1, are dispensable for fertility and gametogenesis in mice.

Meiosis is a critical phase in the life cycle of sexually reproducing organisms. Chromosome numbers are halved during meiosis, which requires meiosis-specific modification of chromosome behaviour. Furthermore, suppression of transposons is particularly important during meiosis to allow the transmission of undamaged genomic information between generations.

Mouse CCDC79 (TERB1) is a meiosis-specific telomere associated protein.

Background: Telomeres have crucial meiosis-specific roles in the orderly reduction of chromosome numbers and in ensuring the integrity of the genome during meiosis. One such role is the attachment of telomeres to trans-nuclear envelope protein complexes that connect telomeres to motor proteins in the cytoplasm. These trans-nuclear envelope connections between telomeres and cytoplasmic motor proteins permit the active movement of telomeres and chromosomes during the first meiotic prophase.

Meiotic DNA double-strand breaks and chromosome asynapsis in mice are monitored by distinct HORMAD2-independent and -dependent mechanisms.

Meiotic crossover formation involves the repair of programmed DNA double-strand breaks (DSBs) and synaptonemal complex (SC) formation. Completion of these processes must precede the meiotic divisions in order to avoid chromosome abnormalities in gametes. Enduring key questions in meiosis have been how meiotic progression and crossover formation are coordinated, whether inappropriate asynapsis is monitored, and whether asynapsis elicits prophase arrest via mechanisms that are distinct from the surveillance of unrepaired DNA DSBs.

Mouse HORMAD1 and HORMAD2, two conserved meiotic chromosomal proteins, are depleted from synapsed chromosome axes with the help of TRIP13 AAA-ATPase.

Meiotic crossovers are produced when programmed double-strand breaks (DSBs) are repaired by recombination from homologous chromosomes (homologues). In a wide variety of organisms, meiotic HORMA-domain proteins are required to direct DSB repair towards homologues. This inter-homologue bias is required for efficient homology search, homologue alignment, and crossover formation.

A novel mammalian HORMA domain-containing protein, HORMAD1, preferentially associates with unsynapsed meiotic chromosomes.

HORMA domain-containing proteins regulate interactions between homologous chromosomes (homologs) during meiosis in a wide range of eukaryotes. We have identified a mouse HORMA domain-containing protein, HORMAD1, and biochemically and cytologically shown it to be associated with the meiotic chromosome axis. HORMAD1 first accumulates on the chromosomes during the leptotene to zygotene stages of meiotic prophase I.

Fluorescence activated cell sorting of live female germ cells and somatic cells of the mouse fetal gonad based on forward and side scattering.

Analysis of female mammalian germ cells has been hindered by difficulties in isolating high purity germ cell populations from embryonic and fetal gonads. Meiotic prophase stage oocytes are particularly difficult to isolate due to the lack of suitable surface markers. Oct4 promoter driven GFP expression has been used to distinguish germ cells/oocytes (GFP positive) from somatic cells (GFP negative), however, the requirement for transgenic animals has limited the use of this technique.