Uncoupled Embryonic and Extra-Embryonic Tissues Compromise Blastocyst Development after Somatic Cell Nuclear Transfer

Somatic cell nuclear transfer (SCNT) is the most efficient cell reprogramming technique available, especially when working with bovine species. Although SCNT blastocysts performed equally well or better than controls in the weeks following embryo transfer at Day 7, elongation and gastrulation defects were observed prior to implantation. To understand the developmental implications of embryonic/extra-embryonic interactions, the morphological and molecular features of elongating and gastrulating tissues were analysed. At Day 18, 30 SCNT conceptuses were compared to 20 controls (AI and IVP: 10 conceptuses each); one-half of the SCNT conceptuses appeared normal while the other half showed signs of atypical elongation and gastrulation. SCNT was also associated with a high incidence of discordance in embryonic and extra-embryonic patterns, as evidenced by morphological and molecular “uncoupling”. Elongation appeared to be secondarily affected; only 3 of 30 conceptuses had abnormally elongated shapes and there were very few differences in gene expression when they were compared to the controls. However, some of these differences could be linked to defects in microvilli formation or extracellular matrix composition and could thus impact extra-embryonic functions. In contrast to elongation, gastrulation stages included embryonic defects that likely affected the hypoblast, the epiblast, or the early stages of their differentiation. When taking into account SCNT conceptus somatic origin, i.e. the reprogramming efficiency of each bovine ear fibroblast (Low: 0029, Med: 7711, High: 5538), we found that embryonic abnormalities or severe embryonic/extra-embryonic uncoupling were more tightly correlated to embryo loss at implantation than were elongation defects. Alternatively, extra-embryonic differences between SCNT and control conceptuses at Day 18 were related to molecular plasticity (high efficiency/high plasticity) and subsequent pregnancy loss. Finally, because it alters re-differentiation processes in vivo, SCNT reprogramming highlights temporally and spatially restricted interactions among cells and tissues in a unique way

Associations between Plasmatic Polyunsaturated Fatty Acids Concentrations and Cognitive Status and Decline in Neurocognitive Disorders

International audienceTo examine the association of plasmatic and erythrocyte concentrations polyunsaturated fatty acids (PUFA) with both cognitive status and decline. Longitudinal observational cohort study. Setting: Memory Clinic of Lyon Sud university hospital. 140 patients, aged 60 and older, were referred to the memory clinic, and successively included in the cohort, between March 2010 and February 2014. Concentration of omega-3 PUFA (eicosapentaenoic: EPA and docosahexaenoic: DHA) and omega-6 PUFA (arachidonic: AA), were measured at baseline in plasma and in the erythrocytes membrane. Cognitive status was assessed using the mini mental state examination (MMSE), at baseline and every six months during follow-up. The median follow-up period was of 11,5 months. Compared to participants with minor neurocognitive disorders (MMSEae24), participants with major neurocognitive disorders (NCD) had lower plasmatic concentrations of EPA and DHA (p \textless 0.05) at baseline. Erythrocyte AA and DHA concentrations were significantly lower in patients with cognitive decline (defined as a ae2 points loss of MMSE per year), while no difference in plasmatic concentrations was observed. Our study suggests that omega-3 PUFA plasma concentrations (mainly EPA and DHA) could be associated with cognitive status in older people. Moreover, in this exploratory study, lower erythrocyte PUFA concentrations (AA and DHA) were associated with accelerated decline and could be proposed as a surrogate marker for prediction of cognitive decline

Deciphering the genetic regulation of peripheral blood transcriptome in pigs through expression genome-wide association study and allele-specific expression analysis

Background: Efforts to improve sustainability in livestock production systems have focused on two objectives: investigating the genetic control of immune function as it pertains to robustness and disease resistance, and finding predictive markers for use in breeding programs. In this context, the peripheral blood transcriptome represents an important source of biological information about an individual ’ s health and immunological status, and has been proposed for use as an intermediate phenotype to measure immune capacity. The objective of this work was to study the genetic architecture of variation in gene expression in the blood of healthy young pigs using two approaches: an expression genome-wide association study (eGWAS) and allele-specific expression (ASE) analysis. [br/] Results: The blood transcriptomes of 60-day-old Large White pigs were analyzed by expression microarrays for eGWAS (242 animals) and by RNA-Seq for ASE analysis (38 animals). Using eGWAS, the expression levels of 1901 genes were found to be associated with expression quantitative trait loci (eQTLs). We recovered 2839 local and 1752 distant associations (Single Nucleotide Polymorphism or SNP located less or more than 1 Mb from expression probe, respectively). ASE analyses confirmed the extensive cis -regulation of gene transcription in blood, and revealed allelic imbalance in 2286 SNPs, which affected 763 gene s. eQTLs and ASE-genes were widely distributed on all chromosomes. By analyzing mutually overlapping eGWAS results, we were able to describe putative regulatory networks, which were further refined using ASE data. At the functional level, genes with genetically controlled expression that were detected by eGWAS and/or ASE analys es were significantly enriched in biological processes related to RNA processing and immune function. Indeed, numerous distant and local regulatory relationships were detected within the major histocompatibility complex region on chromosome 7, revealing ASE for most class I and II genes. Conclusions : This study represents, to the best of our knowledge, the first genome-wide map of the genetic control of gene expression in porcine peripheral blood. T hese results represent an interesting resource for the identification of genetic markers and blood biomarkers associated with variations in immunity traits in pigs, as well as any other complex traits for which blood is an appropriate surrogate tissue

Transcription from a gene desert in a melanoma porcine model

International audienceThe genetic mechanisms underlying cutaneous melanoma onset and progression need to be further understood to improve patients' care. Several studies have focused on the genetic determinism of melanoma development in the MeLiM pig, a biomedical model of cutaneous melanoma. The objective of this study was to better describe the influence of a particular genomic region on melanoma progression in the MeliM model. Indeed, a large region of theSus scrofachromosome 1 has been identified by linkage and association analyses, but the causal mechanisms have remained elusive. To deepen the analysis of this candidate region, a dedicated SNP panel was used to fine map the locus, downsizing the interval to less than 2 Mb, in a genomic region located within a large gene desert. Transcription from this locus was addressed using a tiling array strategy and further validated by RT-PCR in a large panel of tissues. Overall, the gene desert showed an extensive transcriptional landscape, notably dominated by repeated element transcription in tumor and fetal tissues. The transcription of LINE-1 and PERVs has been confirmed in skin and tumor samples from MeLiM pigs. In conclusion, although this study still does not identify a candidate mutation for melanoma occurrence or progression, it highlights a potential role of repeated element transcriptional activity in the MeLiM model

Inferring the evolution of the major histocompatibility complex of wild pigs and peccaries using hybridisation DNA capture-based sequencing

The major histocompatibility complex (MHC) is a key genomic model region for understanding the evolution of gene families and the co-evolution between host and pathogen. To date, MHC studies have mostly focused on species from major vertebrate lineages. The evolution of MHC classical (Ia) and non-classical (Ib) genes in pigs has attracted interest because of their antigen presentation roles as part of the adaptive immune system. The pig family Suidae comprises over 18 extant species (mostly wild), but only the domestic pig has been extensively sequenced and annotated. To address this, we used a DNA-capture approach, with probes designed from the domestic pig genome, to generate MHC data for 11 wild species of pigs and their closest living family, Tayassuidae. The approach showed good efficiency for wild pigs (~80% reads mapped, ~87× coverage), compared to tayassuids (~12% reads mapped, ~4× coverage). We retrieved 145 MHC loci across both families. Phylogenetic analyses show that the class Ia and Ib genes underwent multiple duplications and diversifications before suids and tayassuids diverged from their common ancestor. The histocompatibility genes mostly form orthologous groups and there is genetic differentiation for most of these genes between Eurasian and sub-Saharan African wild pigs. Tests of selection showed that the peptide-binding region of class Ib genes was under positive selection. These findings contribute to better understanding of the evolutionary history of the MHC, specifically, the class I genes, and provide useful data for investigating the immune response of wild populations against pathogens

Genes differently expressed in adipose tissue of dairy cows carrying 'fertil+' or 'fertil-' haplotype for one QTL of female fertility located on the chromosome 3

Session 29Présentation 7absen

Additional file 4: Table S3. of Deciphering the genetic regulation of peripheral blood transcriptome in pigs through expression genome-wide association study and allele-specific expression analysis

ASE analysis results. (XLSX 126 kb

Additional file 11: Figure S4. of Deciphering the genetic regulation of peripheral blood transcriptome in pigs through expression genome-wide association study and allele-specific expression analysis

Gene association network centered on eQTL-SNP H3GA0029721. A: Circo plot produced by R package RCirco which maps eQTL-SNP H3GA0029721 and its associated genes according to their genomic position. The blue links represent associations between this eQTL-SNP on SSC10 and 47 genes that map onto other chromosomes. B: The distribution of all (grey) and significant (red) correlation coefficients calculated from pairwise comparisons of expression variation in probes associated with H3GA0029721, performed by the PCIT algorithm. (PDF 131 kb

Football (association) / par N. G. Tunmer,... et Eugène Fraysse,... ; [avant-propos par G. de Saint-Clair]

Collection : Petite bibliothèque athlétiqueContient une table des matièresAvec mode text

Vitrification alters rabbit foetal placenta at transcriptomic and proteomic level

Although numerous studies have demonstrated that cryopreservation alters gene expression of early embryos and questions the neutrality of the technique in adulthood, less is known about those embryos that implanted successfully and continued in gestation. To raise the question of the neutrality of this technique, we examine the effects of vitrification through the rabbit gestation before and after the implantation. We monitored the distribution of losses of 569 vitrified morulae, observing that embryos which reach the last pre-implantatory stage are able to implant. However, we found that not all implanted embryos had the ability to continue with their gestation. The results reveal that vitrification decreased foetus and maternal placenta weights at mid-gestation, but led to a higher offspring birth weight. A novel finding is that while no differences in gene expression were detected in pre-implantatory embryos at day 6, vitrification affects a gene and protein expression in the placenta at day 14. Our results reveal for first time strong evidence of modifications in implanted embryos subjected to vitrification, suggesting that the crucial step that vitrified embryos must overcome is the placenta formation. Based on these findings, our work leaves the question open as to whether the effects we observed that cause vitrification during foetal development could give rise to some type of physiological or metabolic alteration in adulthood.This work was supported by the Generalitat Valenciana research program (Prometeo 2009/125) and the Spanish Research Projects (CICYT AGL2011-29831-C03-01). M D Saenz-de-Juano was supported by a research grant from Generalitat Valenciana (Programa VALI+d, ACIF/2011/254).Saenz De Juano Ribes, MDLD.; Marco Jiménez, F.; Schmaltz-Panneau, B.; Jiménez Trigos, ME.; Viudes De Castro, MP.; Peñaranda, D.; Jouneau, L.... (2014). Vitrification alters rabbit foetal placenta at transcriptomic and proteomic level. Reproduction. 147(6):789-801. doi:10.1530/REP-14-0019S789801147