Biology subjects

Fekete-Szücs, E.

Publications and source records attributed to Fekete-Szücs, E..

3 recordsLinked to original sources

bioRxiv2023

Deletion of MEC1 suppresses replicative senescence of the cdc13-2 mutant in Saccharomyces cerevisiae

In Saccharomyces cerevisiae, telomerase recruitment to telomeres depends on a direct interaction between Cdc13, a protein that binds single-stranded telomeric DNA, and the Est1 subunit of telomerase. The cdc13-2 allele disrupts telomerase association with telomeres, resulting in progressive telomere shortening and replicative senescence. The Mec1/ATR kinase is both a positive and negative regulator of telomerase activity, and is required for the cell cycle arrest in telomerase-deficient senescent cells. In this study, we find that deletion of MEC1 suppresses the replicative senescence of cdc13-2. This suppression is dependent on telomerase, indicating that Mec1 antagonizes telomerase-mediated telomere extension in cdc13-2 cells to promote senescence.

molecular biology↗

bioRxiv2021

Suppression of cdc13-2-associated senescence by pif1-m2 requires Ku-mediated telomerase recruitment

In Saccharomyces cerevisiae, recruitment of telomerase to telomeres requires an interaction between Cdc13, which binds single-stranded telomeric DNA, and the Est1 subunit of telomerase. A second pathway involving an interaction between the yKu complex and telomerase RNA (TLC1) contributes to telomerase recruitment, but cannot sufficiently recruit telomerase on its own to prevent replicative senescence when the primary Cdc13-Est1 pathway is abolished--for example, in the cdc13-2 mutant. In this study, we find that mutation of PIF1, which encodes a helicase that inhibits telomerase, suppresses the replicative senescence of cdc13-2 increasing reliance on the yKu-TLC1 pathway for telomerase recruitment. Our findings reveal new insight into telomerase-mediated telomere maintenance.

molecular biology↗

bioRxiv2021

Hülle-cell-mediated protection of fungal reproductive and overwintering structures against fungivorous animals

Fungal Hulle cells with nuclear storage and developmental backup functions are reminiscent of multipotent stem cells. In the soil, Hulle cells nurse the overwintering fruiting bodies of Aspergillus nidulans. The genome of A. nidulans harbors genes for the biosynthesis of xanthones. We show that enzymes and metabolites of this biosynthetic pathway accumulate in Hulle cells under the control of the regulatory velvet complex, which coordinates development and secondary metabolism. Deletion strains blocked in the conversion of anthraquinones to xanthones are delayed in maturation and growth of fruiting bodies. Xanthones are not required for sexual development but exert antifeedant effects on fungivorous animals such as springtails and woodlice. These findings reveal a novel role of Hulle cells in establishing secure niches for A. nidulans by accumulating metabolites with antifeedant activity that protect reproductive structures from animal predators.

biochemistry↗