Educational ecosystems for Information Science: the case of the University of Pisa

Interdisciplinarity is becoming increasingly important in education. With the rapidly evolving job market, an interdisciplinary education can prepare students for the flexibility and broad knowledge base required to adapt. At the University of Pisa, we recognized the value of an interdisciplinary educational environment during our participation in the European project EINFOSE, where we harmonized the entry requirements for master programs in Information Science. Prior to this project, we had been building study programs in Digital Humanities and Data Science, whose intersection organically nurtured a diverse learning space. Through this lens, we will reflect on the obstacles constituted by disciplinary barriers and stress the importance of a flexible and open ‘ecosystem’ for education. These conclusions will be supported by data analysis on the careers of our students over the last eight years

An Eye on the Wnt Inhibitory Factor Wif1

The coordinated interplay between extrinsic activating and repressing cell signaling molecules is pivotal for embryonic development and subsequent tissue homeostasis. This is well exemplified by studies on the evolutionarily conserved Wnt signaling pathways. Tight temporal and spatial regulation of Wnt signaling activity is required throughout lifetime, from maternal stages before gastrulation until and throughout adulthood. Outside cells, the action of numerous Wnt ligands is counteracted and fine-tuned by only a handful of well characterized secreted inhibitors, such as for instance Dickkopf, secreted Frizzled Related Proteins and Cerberus. Here, we give an overview of our current understanding of another secreted Wnt signaling antagonist, the Wnt inhibitory factor Wif1. Wif1 can directly interact with various Wnt ligands and inhibits their binding to membrane bound receptors. Epigenetic promoter methylation of Wif1, leading to silencing of its transcription and concomitant up-regulation of Wnt signaling, is a common feature during cancer progression. Furthermore, an increasing number of reports describe Wif1 involvement in regulating processes during embryonic development, which so far has not received as much attention. We will summarize our knowledge on Wif1 function and its mode of action with a particular focus on the zebrafish (Danio rerio). In addition, we highlight the potential of Wif1 research to understand and possibly influence mechanisms underlying eye diseases and regeneration

Retinal defects in mice lacking the autism-associated gene Engrailed-2

Defective cortical processing of visual stimuli and altered retinal function have been described in autism spectrum disorder (ASD)patients. In keeping with these findings, anatomical and functional defects have been found in the visual cortex and retina of mice bearing mutations for ASD-associated genes. Here we sought to investigate the anatomy and function of the adult retina of Engrailed 2 knockout (En2 −/− )mice, a model for ASD. Our results showed that En2 is expressed in all three nuclear layers of the adult retina. When compared to age-matched En2 +/+ controls, En2 −/− adult retinas showed a significant decrease in the number of calbindin + horizontal cells, and a significant increase in calbindin + amacrine/ganglion cells. The total number of ganglion cells was not altered in the adult En2 −/− retina, as shown by Brn3a + cell counts. In addition, En2 −/− adult mice showed a significant reduction of photoreceptor (rhodopsin)and bipolar cell (Pcp2, PKCα)markers. Functional defects were also present in the retina of En2 mutants, as indicated by electroretinogram recordings showing a significant reduction in both a-wave and b-wave amplitude in En2 −/− mice as compared to controls. These data show for the first time that anatomical and functional defects are present in the retina of the En2 ASD mouse model

TMEM16A is associated with voltage-gated calcium channels in mouse retina and its function is disrupted upon mutation of the auxiliary α2δ4 subunit

Photoreceptors rely upon highly specialized synapses to efficiently transmit signals to multiple postsynaptic targets. Calcium influx in the presynaptic terminal is mediated by voltage-gated calcium channels (VGCC). This event triggers neurotransmitter release, but also gates calcium-activated chloride channels (TMEM), which in turn regulate VGCC activity. In order to investigate the relationship between VGCC and TMEM channels, we analyzed the retina of wild type (WT) and Cacna2d4 mutant mice, in which the VGCC auxiliary a2d4 subunit carries a nonsense mutation, disrupting the normal channel function. Synaptic terminals of mutant photoreceptors are disarranged and synaptic proteins as well as TMEM16A channels lose their characteristic localization. In parallel, calcium-activated chloride currents are impaired in rods, despite unaltered TMEM16A protein levels. Co-immunoprecipitation revealed the interaction between VGCC and TMEM16A channels in the retina. Heterologous expression of these channels in tsA-201 cells showed that TMEM16A associates with the CaV1.4 subunit, and the association persists upon expression of the mutant a2d4 subunit. Collectively, our experiments show association between TMEM16A and the a1 subunit of VGCC. Close proximity of these channels allows optimal function of the photoreceptor synaptic terminal under physiological conditions, but also makes TMEM16A channels susceptible to changes occurring to calcium channels

A new splicing isoform of Cacna2d4 mimicking the effects of c.2451insC mutation in the retina: Novel molecular and electrophysiological insights

PURPOSE. Mutations in CACNA2D4 exon 25 cause photoreceptor dysfunction in humans (c.2406CA mutation) and mice (c.2451insC mutation). We investigated the feasibility of an exon-skipping therapeutic approach by evaluating the splicing patterns and functional role of targeted exons. METHODS. Splicing of the targeted a2d4 (CACNA2D4) exons in presence and absence of the mutation was assessed by RT-PCR in vivo on mouse retinae and in vitro in HEK293T cells using splicing-reporter minigenes. Whole-cell patch-clamp recordings were performed to evaluate the impact of different Cacna2d4 variants on the biophysical properties of Cav1.4 Ltype calcium channels (CACNA1F). RESULTS. Splicing analysis revealed the presence of a previously unknown splicing isoform of a2d4 in the retina that truncates the gene open reading frame (ORF) in a similar way as the c.2451insC mutation. This isoform originates from alternative splicing of exon 25 (E25) with a new exon (E25b). Moreover, the c.2451insC mutation has an effect on splicing and increases the proportion of transcripts including E25b. Our electrophysiological analyses showed that only full-length a2d4 was able to increase Cav1.4/b3-mediated currents while all other a2d4 variants did not mediate such effect. CONCLUSIONS. The designed exon-skipping strategy is not applicable because the resulting skipped a2d4 are nonfunctional. a2d4 E25b splicing variant is normally present in mouse retina and mimics the effect of c.2451insC mutation. Since this variant does not promote significant Cav1.4-mediated calcium current, it could possibly mediate a different function, unrelated to modulation of calcium channel properties at the photoreceptor terminals

Educational ecosystems for Information Science: The case of the University of Pisa

Interdisciplinarity is becoming increasingly important in education. With the rapidly evolving job market, an interdisciplinary education can prepare students for the flexibility and broad knowledge base required to adapt. At the University of Pisa, we recognized the value of an interdisciplinary educational environment during our participation in the European project EINFOSE, where we harmonized the entry requirements for master programs in Information Science. Prior to this project, we had been building study programs in Digital Humanities and Data Science, whose intersection organically nurtured a diverse learning space. Through this lens, we will reflect on the obstacles constituted by disciplinary barriers and stress the importance of a flexible and open ‘ecosystem’ for education. These conclusions will be supported by data analysis on the careers of our students over the last eight years