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Biology subjects

Barbon, A.

Publications and source records attributed to Barbon, A..

3 recordsLinked to original sources

Functional Impact of CYFIP2 RNA Editing on Actin Regulation, Axon Growth, and Spinogenesis

Cytoplasmic FMRP Interacting Protein 2 (CYFIP2) a component of the Wave Regulatory Complex (WRC), one of the most important players in regulating cellular actin dynamics. Interestingly, CYFIP2 transcript undergoes RNA editing, an epitranscriptomic modification catalysed by ADAR enzymes, that leads adenosine (A) to inosine (I) deamination. CYFIP2 editing in the coding sequence results in a K/E substitution at amino acid 320. The functional meaning of this regulation is still unknown. In this study, we aim at investigating the potential implication of CYFIP2 RNA editing related to actin dynamics during cell differentiation, axon development and synaptogenesis in neural cells. We have generated SH-SY5Y neuroblastoma cell lines in which CYFIP2 gene has been functionally inactivated by CRISPR-Cas9 technology. CYFIP2 KO cells showed profound actin filaments disorganisation and loss of the capability to differentiate into a neuronal-like phenotype. Overexpression of both CYFIP2 unedited (K) and edited (E) isoforms rescued normal capability. Finally, we took advantage of primary neuronal culture where endogenous CYFIP2 was knocked down by shRNA technology and CYFIP2 editing variants were overexpressed. While CYFIP2 KD cells reported a decrease in axon development and spine frequency, CYFIP2-E variants increase the number of axon branches, total axon length and dendritic spine frequency compared to either CYFIP2 KD cells or CYFIP-K variants. Overall, our work reveals for the first time a functional significance of the CYFIP2 K/E RNA editing process in regulating the spreading of neuronal axons during the initial stages of in-vitro development and the process of spinogenesis.

cell biology↗

Eurasian Stone-curlews Burhinus oedicnemus breeding in Italy show a remarkable inter and intra-population variability of migratory behaviour

Migratory behaviour in birds shows a remarkable variability at species, population and individual levels. Short-distance migrants, in particular, often adopt a partial migratory strategy and tend to have a rather flexible migration schedule which allows them to respond more effectively to extreme environmental variations, like those due to climate change. Weather seasonality and environmental heterogeneity at regional and local scales have been reported as significant factors in the diversification of migratory behaviour for some species of Mediterranean migrants. Relatively few studies, however, investigated the migration patterns of non-passerine birds migrating within this area. In this study we investigated the migratory strategy of the Eurasian Stone-curlew Burhinus oedicnemus using data collected on 40 individuals tagged with geolocators and GPS-GSM tags, belonging to two continental and two Mediterranean populations of the Italian peninsula. The proportion of migrants was significantly higher in continental populations, but we observed a significant variability also within Mediterranean populations. GPS-tagged migrants traveled less than 1000 km, spending the winter within the Mediterranean basin. Continental Stone-curlews i) departed earlier in spring and later in autumn and ii) covered longer distances than those from Mediterranean areas. The speed of migration did not change between seasons for continental birds, while Mediterranean individuals tended to migrate faster in spring. The likelihood of departure for autumn migration of GPS-tagged birds significantly increased when temperatures were near or below 0 {degrees}C suggesting that Stone-curlews tend to delay departure weather conditions worsen abruptly. Thus it can be speculated that the frequency of migratory birds in the considered populations may decrease in the near future due to the effect of global warming in the Mediterranean. This could have a significant effect on the distribution of species throughout the year and should be taken into account when targeting conservation measures.

zoology↗

Genome-wide analysis of RNA editing levels in human blood identified interactions with mRNA processing genes and suggested correlations with biological and drug-related variables

BackgroundA-to-I RNA editing is a co-/post-transcriptional modification catalyzed by ADAR enzymes, that deaminates Adenosines (A) into Inosines (I). Most of known editing events are located within inverted ALU repeats, but they also occur in coding sequences and may alter the function of encoded proteins. RNA editing contributes to generate transcriptomic diversity and it is found altered in cancer, autoimmune and neurological disorders. Emerging evidences indicate that editing process could be influenced by genetic variations, biological and environmental variables.\n\nResultsWe analyzed RNA editing levels in human blood using RNA-seq data from 459 healthy individuals and identified 2,079 sites consistently edited in this tissue. As expected, analysis of gene expression revealed that ADAR is the major contributor to editing on these sites, explaining [~]13% of observed variability. After removing ADAR effect, we found significant associations for 1,122 genes, mainly involved in RNA processing. These genes were significantly enriched in genes encoding proteins interacting with ADARs, including 276 potential ADARs interactors and 9 ADARs direct partners. In addition, our analysis revealed several factors potentially influencing RNA editing in blood, including cell composition, age, Body Mass Index, smoke and alcohol consumption. Finally, we identified genetic loci associated with editing levels, including known ADAR eQTLs and a small region on chromosome 7, containing LOC730338, a lincRNA gene that appears to modulate ADARs mRNA expression.\n\nConclusionsOur data provides a detailed picture of the most relevant RNA editing events and their variability in human blood, giving interesting insights on potential mechanisms behind this post-transcriptional modification and its regulation in this tissue.

genomics↗