Biology subjects

Fontanesi, L.

Publications and source records attributed to Fontanesi, L..

4 recordsLinked to original sources

bioRxiv2022

Discovering genomic regions associated with the phenotypic differentiation of European local pig breeds

BackgroundIntensive selection of modern pig breeds resulted in genetic improvement of productive traits while local pig breeds remained less performant. As they have been bred in extensive systems, they have adapted to specifical environmental conditions resulting in a rich genotypic and phenotypic diversity. This study is based on European local pig breeds genetically characterized using DNA-pool sequencing data and phenotypically characterized using breed level phenotypes related to stature, fatness, growth and reproductive performance traits. These data were analyzed using a dedicated approach to detect selection signatures linked to phenotypic traits in order to uncover potential candidate genes that may be under adaptation to specific environments. ResultsGenetic data analysis of European pig breeds revealed four main axes of genetic variation represented by Iberian and modern breeds (i.e. Large White, Landrace, and Duroc). In addition, breeds clustered according to their geographical origin, for example French Gascon and Basque breeds, Italian Apulo Calabrese and Casertana breeds, Spanish Iberian and Portuguese Alentejano breeds. Principal component analysis of phenotypic data distinguished between larger and leaner breeds with better growth potential and reproductive performance on one hand and breeds that were smaller, fatter, and had low growth and reproductive efficiency on the other hand. Linking selection signatures with phenotype identified 16 significant genomic regions associated with stature, 24 with fatness, 2 with growth and 192 with reproduction. Among them, several regions contained candidate genes with possible biological effect on stature, fatness, growth and reproduction performance traits. For example, strong associations were found for stature in two regions containing the ANXA4 and ANTXR1 genes, for fatness containing the DNMT3A and POMC genes and for reproductive performance containing the HSD17B7 gene. ConclusionsThe present study on European local pig breeds used a dedicated approach for searching selection signatures supported by phenotypic data at the breed level to identify potential candidate genes that may have adapted to different living environments and production systems. Results can be useful to define conservation programs of local pig breeds.

genetics↗

bioRxiv2021

Disentangling choice value and choice conflict in sequential decisions under risk

Recent years have witnessed a surge of interest in understanding the neural and cognitive dynamics that drive sequential decision making in general and foraging behavior in particular. Due to the intrinsic properties of most sequential decision-making paradigms, however, previous research in this area has suffered from the difficulty to disentangle properties of the decision related to (a) the value of switching to a new patch versus (b) the conflict experienced between choosing to stay or leave. Here, we show how the same problems arise in studies of sequential decision-making under risk, and how they can be overcome, taking as a specific example recent research on the pig dice game. In each round of the pig dice game, people roll a die and accumulate rewards until they either decide to proceed to the next round or lose all rewards. By combining simulation-based dissections of the task structure with two experiments, we show how an extension of the standard paradigm, together with cognitive modeling of decision-making processes, disentangles value-from conflict-related choice properties. Our study elucidates the cognitive mechanisms of sequential decision making and underscores the importance of avoiding potential pitfalls of paradigms that are commonly used in this research area.

animal behavior and cognition↗

bioRxiv2019

The role of dopaminergic nuclei in predicting and experiencing gains and losses: A 7T human fMRI study

The ability to predict the outcomes of actions based on experience is crucial for making successful decisions in new or dynamic environments. In animal studies using electrophysiology, it was found that dopamine neurons, located in the substantia nigra (SN) and the ventral tegmental area (VTA), have a crucial role in feedback-based learning. However, human neuroimaging studies have provided inconclusive results. The present work used ultrahigh field (7 Tesla) structural and functional MRI and optimized protocols to extract SN and VTA signals in human participants. In a number-guessing task, we found significant correlations with reward prediction error and risk in both the SN and the VTA and no correlation with expected value. We also found a surprise signal in the SN. These results are in line with a recent framework that proposed a differential role for the VTA and the SN in, respectively, learning of values and surprise.

neuroscience↗

bioRxiv2018

A comparative analysis of label-free liquid chromatography-mass spectrometry liver proteomic profiles highlights metabolic differences between pig breeds

Liver is a complex organ governing several physiological processes that define biological mechanisms affecting growth, feed efficiency and performance traits in all livestock species, including the pig. Proteomics may contribute to better understand the relationship between liver functions and complex production traits in pigs and to characterize this specie as biomedical model. This study applied, for the first time, a label-free liquid chromatography-mass spectrometry (LC-MS) proteomic approach to compare the liver proteome profiles of two important heavy pig breeds, Italian Duroc (IDU) and Italian Large White (ILW). Liver specimens were collected (after slaughtering) from performance tested pigs of these two breeds, raised in standard conditions. The label-free LC-MS method captured a total of 501 proteins of which 200 were subsequently considered in the between breeds comparison. A statistical pipeline based on the sparse Partial Least Squares Discriminant Analysis (sPLS-DA), coupled with stability and significance tests, was applied for the identification of up or down regulated proteins between breeds. Analyses revealed a total of 25 proteins clearly separating IDU and ILW pigs. Among the top proteins differentiating the two breeds ACAA2 and CES3 were up-regulated in ILW and HIST2H2BF and KHK were up-regulated in IDU. FASN, involved in fatty acid metabolism and encoded by a gene located in a QTL region for fatty acid composition, was up-regulated in ILW. Protein interaction analysis showed that 16 of these proteins were connected in one big module. Functional analyses indicated that differentially expressed proteins were involved in several biological processes related to the metabolism of lipids, amino-acids, carbohydrates, cofactors and antibiotics/drugs, supporting that these functions might distinguish IDU and ILW pigs. This comparative proteomic analysis of the porcine liver highlighted several biological factors that could determine the peculiar production potentials of these two heavy pig breeds, derived by their different genetic backgrounds.

systems biology↗