Telomere interacting proteins Tert and Terb1 regulate meiotic progression in zebrafish

ABSTRACT: Telomeres have a prominent role in meiosis – telomere tethering to nuclear envelope proteins is essential for successful meiosis and fertility. This is accomplished through meiosis-specific telomere adaptor complexes that interacts with protein complexes spanning the nuclear envelop to connect with motor proteins. Connecting telomeres to motor proteins through this protein chain drives rapid prophase I movements (RPM) of chromosomes, which results in clustering of telomeres at one side of the nucleus to form the meiotic bouquet. Telomere attachment to the nuclear envelop proteins and RPMs are essential for homologue chromosome pairing, synapsis, and meiotic recombination. Mutations disrupting telomerase reverse transcriptase (tert) result in multiple pathologies including impaired fertility. Here, we investigate effects of loss of tert function on meiosis in zebrafish. We demonstrate that tert mutant meiotic germ cells have shortened telomeres and display defects in meiotic progression with eventual loss of meiotic cells with age, followed by loss of mitotic germ cells several months later. These data indicate that meiotic cells are more sensitive to shortened telomeres than mitotic germ cells. Furthermore, we found that orthologues to the mouse meiotic telomere adaptor complex genes, terb1, terb2, and majin, are expressed primarily in meiotic germ cells in zebrafish. Through mutant analysis we show that zebrafish terb1 is necessary for formation of the meiotic bouquet and completion of meiosis, suggesting that zebrafish Terb1 functions as a meiotic telomere adaptor protein, similar to mouse Terb1. These data point to the importance of telomere maintenance and telomere associated proteins in meiotic prophase I during spermatogenesis.

ORGANISM(S): Danio rerio

PROVIDER: GSE317627 | GEO | 2026/04/15

REPOSITORIES: GEO