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Cellerino, A.

Publications and source records attributed to Cellerino, A..

4 recordsLinked to original sources

Clownfishes are a genetic model of exceptional longevity and reveal molecular convergence in the evolution of lifespan

Standard evolutionary theories of aging postulate that reduced extrinsic mortality leads to evolution of longevity. Clownfishes of the genus Amphiprion live in a symbiotic relationship with sea anemones that provide protection from predation. We performed a survey and identified at least two species with lifespan of over 20 years. Given their small size and ease of captive reproduction, clownfishes lend themselves as experimental models of exceptional longevity.\n\nTo identify genetic correlates of exceptional longevity, we sequenced the transcriptomes of Amphiprion percula and A. clarkii and performed a scan for positively-selected genes (PSGs). These were compared with PSGs detected in long-lived mole rats and short-lived killifishes revealing convergent evolution in processes such as mitochondrial biogenesis. Among individual genes, the Mitochondrial Transcription Termination Factor 1 (MTERF1), was positively-selected in all three clades, whereas the Glutathione S-Transferase Kappa 1 (GSTK1) was under positive selection in two independent clades. For the latter, homology modelling strongly suggested that positive selection targeted enzymatically important residues.\n\nThese results indicate that specific pathways were recruited in independent lineages evolving an exceptionally extended or shortened lifespan and point to mito-nuclear balance as a key factor.

evolutionary biology

The age-regulated zinc finger factor ZNF367 is a new modulator of embryonic neurogenesis

Global population aging is one of the major social and economic challenges of contemporary society. During aging the progressive decline in physiological functions has serious consequences for all organs including brain. The age-related incidence of neurodegenerative diseases coincides with the sharp decline of the amount and functionality of adult neural stem cells. Recently, we identified a short list of brain age-regulated genes by means of next-generation sequencing. Among them znf367 codes for a transcription factor that represents a central node in gene coregulation networks during aging but its function, in the central nervous system (CNS), is completely unknown. As proof of concept we analyzed the role of znf367 during neurogenesis. By means of a gene loss of function approach limited to the CNS, we suggested that znf367 might act as a key controller of the neuroblasts cell cycle, particularly in the progression of mitosis and spindle check-point. Using a candidate gene approach, based on a weighted-gene co-expression network analysis, we suggested possible targets of znf367 such as fancd2 and ska3. The age-related decline of znf367 well correlated with its role during embryonic neurogenesis opening new lines of investigation to improved maintenance and even repair of neuronal function.

developmental biology

Long-lived rodents reveal signatures of positive selection in genes associated with lifespan and eusociality

The genetic mechanisms that determine lifespan are poorly understood. Most research has been done on short lived animals and it is unclear if these insights can be transferred to long-lived mammals like humans. Some African mole-rats (Bathyergidae) have life expectancies that are multiple times higher than similar sized and phylogenetically closely related rodents. We obtained genomic and transcriptomic data from 17 rodent species and systematically scanned eleven lineages associated with the evolution of longevity and eusociality for positively selected genes (PSGs). The set of 319 PSGs contains regulators of mTOR and is enriched in functional terms associated with (i) processes that are regulated by the mTOR pathway, e.g. translation, autophagy and mitochondrial biogenesis, (ii) the immune system and (iii) antioxidant defense. Analyzing gene expression of PSGs during aging in the long-lived naked mole-rat and up-regulation in the short-lived rat, we found a pattern fitting the antagonistic pleiotropy theory of aging.

evolutionary biology

A miRNA catalogue and ncRNA annotation of theshort-living fish Nothobranchius furzeri

Background: The short-lived fish Nothobranchius furzeri is the shortest-lived vertebrate that can be cultured in captivity and was recently established as a model organism for aging research. Small non-coding RNAs, especially miRNAs, are implicated in age-dependent control of gene expression.\n\nResults: Here, we present a comprehensive catalogue of miRNAs and several other non-coding RNA classes (ncRNAs) for Nothobranchius furzeri. Analyzing multiple small RNA-Seq libraries, we show most of these identified miRNAs are expressed in at least one of seven Nothobranchius species. Additionally, duplication and clustering of N. furzeri miRNAs was analyzed and compared to the four fish species Danio rerio, Oryzias latipes, Gasterosteus aculeatus and Takifugu rubripes. A peculiar characteristic of N. furzeri as compared to other teleosts was a duplication of the miR-29 cluster.\n\nConclusion: The completeness of the catalogue we provide is comparable to that of zebrafish. This catalogue represents a basis to investigate the role of miRNAs in aging and development in this species.\n\nAvailability: All supplementary material can be found online at http://www.rna.uni-jena.de/en/supplements/nothobranchius-furzeri-mirnome/.

genomics