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Andreatta, G.

Publications and source records attributed to Andreatta, G..

3 recordsLinked to original sources

Cold-sensing TRP channels and temperature preference modulate ovarian development in the model organism Drosophila melanogaster

Temperature is perceived primarily via Transient Receptor Potential (TRP) channels, which are integral to the molecular machinery sensing environmental and cellular signals. Functional evidence of TRP channels involvement in regulating cold-induced developmental/reproductive responses remains scarce. Here we show that mutations affecting cold-sensing TRP channels antagonize the reduction of ovarian development induced by low temperatures (reproductive dormancy) in Drosophila melanogaster. More specifically, mutants for brv1, trp, and trpl significantly lowered dormancy levels at 12{degrees}C, and exhibited well-developed oocytes characterized by advanced vitellogenesis. Similarly, functional knockouts for norpA, a gene encoding a phospholipase C acting downstream to Trp and Trpl, exhibited a reduced dormancy response, suggesting that Ca2+ signalling is key to relaying cold-sensing stimuli during dormancy induction and maintenance. Finally, mutants with altered temperature preference (i.e. exhibiting impaired cold or warm avoidance) differentially responded to cold, either lowering or increasing dormancy levels. In summary, our phenotypic analysis provides functional evidence of developmental/reproductive modulation by specific cold-sensing TRP channels in Drosophila melanogaster, and indicates that temperature preference affects developmental processes. As the studied genes are highly conserved and have mammalian homologues, the potential implications of our findings for human metabolism and drug development are also discussed.

developmental biology↗

A cryptochrome photoreceptor controls animal light-dependent growth and lifespan via evolutionary conserved hormonal pathways

Natural light is severely affected by human impact on Earth, yet little is known about the roles light receptors have outside vision and rhythmic processes. Here we show that loss-of-function of the light-receptive cryptochrome (l-cry) in marine bristleworms significantly increases lifespan and adult size, similarly to wild-types reared in constant darkness. Quantitative transcriptomics revealed hormonal players crucial for invertebrate and vertebrate sexual development and reproduction affected in l-cry mutants. These include nr0b1/2, ortholog of dax-1 (nr0b1) and shp (nr0b2), long considered vertebrate novelties. Depending on moon-phase, nr0b1/2 is up- or down-regulated in l-cry mutants. Matching the complex regulation, loss of nr0b1/2 function partially recapitulates l-cry phenotypes. Molecularly, Platynereis Nr0b1/2 affects steroidogenic and other endocrine pathways, nuclear receptor signaling, and transcription factor orthologs, involved in sexual developmental, reproductive, and timing processes in other organisms. Thus, our study reveals profound effects of light on adult animal life-time, likely at least in part by conserved endocrine pathways involved in sexual maturation and reproduction in annelids and vertebrates.

evolutionary biology↗

A c-opsin functions in a ciliary-marginal zone-like stem cell region of an invertebrate camera-type eye

Camera-type eyes in vertebrates and invertebrates are striking examples of parallel evolution of a complex structure. Comparisons between such structures can help to deduce their organizational principles. We analyzed the camera-type adult eyes of the bristleworm Platynereis dumerilii. Employing single-cell RNA sequencing, we identified neurogenic cells in the worms adult brains. Among those are distinct neural stem cells in its adult eye, adjacent to the glass body/lens, that produce cells in radial lines, reminiscent of stem cells in the vertebrate eye ciliary marginal zone. A subset of these proliferating cells expresses the photoreceptor gene c-opsin1. c-opsin1 knock-out reduces eye cell proliferation and influences differentiation. During reproductive maturation, proliferation in eye and brain sharply declines, while cells upregulate molecular characteristics of mammalian adult neural stem cell quiescence. Our data reveal new insights into nervous system functional development and evolution.

developmental biology↗