Biology subjects

Goshtchevsky, U.

Publications and source records attributed to Goshtchevsky, U..

4 recordsLinked to original sources

bioRxiv2024

The cGAS-STING pathway is an in vivo modifier of genomic instability syndromes

Mutations in genes involved in DNA damage repair (DDR) often lead to premature aging syndromes. While recent evidence suggests that inflammation, alongside mutation accumulation and cell death, may drive disease phenotypes, its precise contribution to in vivo pathophysiology remains unclear. Here, by modeling Ataxia Telangiectasia (A-T) and Bloom Syndrome in the African turquoise killifish (N. furzeri), we replicate key phenotypes of DDR syndromes, including infertility, cytoplasmic DNA fragments, and reduced lifespan. The link between DDR defects and inflammation is attributed to the activation of the cGAS-STING pathway and interferon signaling by cytoplasmic DNA. Accordingly, mutating cGAS partially rescues germline defects and senescence in A-T fish. Double mutants also display reversal of telomere abnormalities and suppression of transposable elements, underscoring cGASs non-canonical role as a DDR inhibitor. Our findings emphasize the role of interferon signaling in A-T pathology and identify the cGAS-STING pathway as a potential therapeutic target for genomic instability syndromes.

genetics↗

bioRxiv2022

Identification of protein aggregates in the aging vertebrate brain with prion-like andphase separation properties

Protein aggregation, which can sometimes spread in a prion-like manner, is a hallmark of neurodegenerative diseases. However, whether prion-like aggregates form during normal brain aging remains unknown. Here we use quantitative proteomics in the African turquoise killifish to identify protein aggregates that accumulate in old vertebrate brains. These aggregates are enriched for prion-like RNA binding proteins, notably the ATP-dependent RNA helicase DDX5. We validate that DDX5 forms mislocalized cytoplasmic aggregates in the brains of old killifish and mice. Interestingly, DDX5s prion-like domain allows these aggregates to propagate across many generations in yeast. In vitro, DDX5 phase separates into condensates. Mutations that abolish DDX5 prion propagation also impair the proteins ability to phase separate. DDX5 condensates exhibit enhanced enzymatic activity, but they can mature into inactive, solid aggregates. Our findings suggest that protein aggregates with prion-like properties form during normal brain aging, which could have implications for the age-dependency of cognitive decline.

neuroscience↗

bioRxiv2022

Tissue-specific landscape of protein aggregation and quality control in an aging vertebrate

Protein aggregation is a hallmark of age-related neurodegeneration. Yet, aggregation during normal aging and in tissues other than the brain is poorly understood. Here we leverage the African turquoise killifish to systematically profile protein aggregates in seven tissues of an aging vertebrate. Age-dependent aggregation is strikingly tissue-specific, and not simply driven by protein expression differences. Experimental interrogation, combined with machine learning, indicates that this specificity is linked to both protein-autonomous biophysical features and tissue-selective alterations in protein quality control. Co-aggregation of protein quality control machinery during aging may further reduce proteostasis capacity, exacerbating aggregate burden. A segmental progeria model with accelerated aging in specific tissues exhibits selectively increased aggregation in these same tissues. Intriguingly, many age-related protein aggregates arise in wild-type proteins that, when mutated, drive human diseases. Our data chart a comprehensive landscape of protein aggregation during aging and reveal strong, tissue-specific associations with dysfunction and disease. HIGHLIGHTSO_LITissue-specific protein aggregation is prevalent during vertebrate aging C_LIO_LIBoth protein biophysical properties and tissue-specific protein homeostasis patterns impact aggregation C_LIO_LIA segmental progeria model with accelerated aging exhibits selectively increased protein aggregation in affected tissues C_LIO_LIMany aggregates that accumulate during physiological aging are linked to disease C_LI

systems biology↗

bioRxiv2022

Sex-specific regulation of metabolic health and vertebrate lifespan by AMP biosynthesis

Energy homeostasis is disrupted with age, which then fuels multiple age-related pathologies. The AMP-activated protein kinase (AMPK) is the primary sensor of cellular energy in eukaryotes. However, the genetic regulation of vertebrate aging by AMPK remains poorly understood. Here, we manipulate energy levels in the turquoise killifish by mutating APRT, a key enzyme in AMP biosynthesis. These manipulations produced a male-specific lifespan extension and restored metabolic plasticity. Exploring the observed sex differences using an integrated omics approach implicated the mitochondria as an important player. Mechanistically, APRT regulated mitochondrial functions and AMPK activity, mimicking energy starvation in heterozygous cells. A fasting-like state was also detected, particularly in heterozygous males, which leads to resistance to high-fat diet. Finally, life-long intermittent fasting eliminated the male-specific longevity benefits mediated by the APRT mutation. These observations identify the AMP/AMPK axis as a sex-specific regulator of vertebrate longevity and metabolic health.

genetics↗