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- Amato, Alberto, et al.
(author)
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Grazer-induced transcriptomic and metabolomic response of the chain-forming diatom Skeletonema marinoi
- 2018
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In: ISME Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 12, s. 1594-1604
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Journal article (peer-reviewed)abstract
- Diatoms and copepods are main actors in marine food webs. The prey-predator interactions between them affect bloom dynamics, shape marine ecosystems and impact the energy transfer to higher trophic levels. Recently it has been demonstrated that the presence of grazers may affect the diatom prey beyond the direct effect of grazing. Here, we investigated the response of the chain-forming centric diatom Skeletonema marinoi to grazer cues, including changes in morphology, gene expression and metabolic profile. S. marinoi cells were incubated with Calanus finmarchicus or with Centropages typicus and in both cases responded by reducing the chain length, whereas changes in gene expression indicated an activation of stress response, changes in the lipid and nitrogen metabolism, in cell cycle regulation and in frustule formation. Transcripts linked to G protein-coupled receptors and to nitric oxide synthesis were differentially expressed suggesting involvement of these signalling transduction pathways in the response. Downregulation of a lipoxygenase in the transcriptomic data and of its products in the metabolomic data also indicate an involvement of oxylipins. Our data contribute to a better understanding of the gene function in diatoms, providing information on the nature of genes implicated in the interaction with grazers, a crucial process in marine ecosystems.
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| 2. |
- Jimenez-Gonzalez, Ada, et al.
(author)
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Paternal starvation affects metabolic gene expression during zebrafish offspring development and lifelong fitness
- 2024
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In: Molecular Ecology. - : John Wiley & Sons. - 0962-1083 .- 1365-294X. ; 33:6
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Journal article (peer-reviewed)abstract
- Dietary restriction in the form of fasting is a putative key to a healthier and longer life, but these benefits may come at a trade-off with reproductive fitness and may affect the following generation(s). The potential inter- and transgenerational effects of long-term fasting and starvation are particularly poorly understood in vertebrates when they originate from the paternal line. We utilised the externally fertilising zebrafish amenable to a split-egg clutch design to explore the male-specific effects of fasting/starvation on fertility and fitness of offspring independently of maternal contribution. Eighteen days of fasting resulted in reduced fertility in exposed males. While average offspring survival was not affected, we detected increased larval growth rate in F1 offspring from starved males and more malformed embryos at 24 h post-fertilisation in F2 offspring produced by F1 offspring from starved males. Comparing the transcriptomes of F1 embryos sired by starved and fed fathers revealed robust and reproducible increased expression of muscle composition genes but lower expression of lipid metabolism and lysosome genes in embryos from starved fathers. A large proportion of these genes showed enrichment in the yolk syncytial layer suggesting gene regulatory responses associated with metabolism of nutrients through paternal effects on extra-embryonic tissues which are loaded with maternal factors. We compared the embryo transcriptomes to published adult transcriptome datasets and found comparable repressive effects of starvation on metabolism-associated genes. These similarities suggest a physiologically relevant, directed and potentially adaptive response transmitted by the father, independently from the offspring's nutritional state, which was defined by the mother.
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| 3. |
- Petrosino, Giuseppe, et al.
(author)
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Identification of LINE retrotransposons and long non-coding RNAs expressed in the octopus brain
- 2022
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In: BMC Biology. - : BMC. - 1741-7007. ; 20:1
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Journal article (peer-reviewed)abstract
- Background Transposable elements (TEs) widely contribute to the evolution of genomes allowing genomic innovations, generating germinal and somatic heterogeneity, and giving birth to long non-coding RNAs (lncRNAs). These features have been associated to the evolution, functioning, and complexity of the nervous system at such a level that somatic retrotransposition of long interspersed element (LINE) L1 has been proposed to be associated to human cognition. Among invertebrates, octopuses are fascinating animals whose nervous system reaches a high level of complexity achieving sophisticated cognitive abilities. The sequencing of the genome of the Octopus bimaculoides revealed a striking expansion of TEs which were proposed to have contributed to the evolution of its complex nervous system. We recently found a similar expansion also in the genome of Octopus vulgaris. However, a specific search for the existence and the transcription of full-length transpositionally competent TEs has not been performed in this genus. Results Here, we report the identification of LINE elements competent for retrotransposition in Octopus vulgaris and Octopus bimaculoides and show evidence suggesting that they might be transcribed and determine germline and somatic polymorphisms especially in the brain. Transcription and translation measured for one of these elements resulted in specific signals in neurons belonging to areas associated with behavioral plasticity. We also report the transcription of thousands of lncRNAs and the pervasive inclusion of TE fragments in the transcriptomes of both Octopus species, further testifying the crucial activity of TEs in the evolution of the octopus genomes. Conclusions The neural transcriptome of the octopus shows the transcription of thousands of putative lncRNAs and of a full-length LINE element belonging to the RTE class. We speculate that a convergent evolutionary process involving retrotransposons activity in the brain has been important for the evolution of sophisticated cognitive abilities in this genus.
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