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F Piumi

Publications and source records attributed to F Piumi.

18 recordsLinked to original sources

Porcine PPARGC1A (peroxisome proliferative activated receptor gamma coactivator 1A): coding sequence, genomic organization, polymorphisms and mapping.

We report here the characterisation of porcine PPARGC1A. Primers based on human PPARGC1A were used to isolate two porcine BAC clones. Porcine coding sequences of PPARGC1A were sequenced together with the splice site regions and the 5' and 3' regions. Using direct sequencing nine SNPs were found. Allele frequencies were determined in unrelated animals of five different pig breeds. In the MARC Meishan-White Composite resource population, the polymorphism in exon 9 was significantly associated with leaf fat weight. PPARGC1A has been mapped by FISH to SSC8p21. A (CA)n microsatellite (SGU0001) has been localised near marker SWR1101 on chromosome 8 by RH mapping and at the same position as marker KS195 (32.5 cM) by linkage mapping. The AseI (nt857, Asn/Asn489) polymorphism in exon 8 was used to perform linkage analysis in the Hohenheim pedigrees and located the gene in the same genomic region. Transcription of the gene was detected in adipose, muscle, kidney, liver, brain, heart and adrenal gland tissues, which is in agreement with the function of PPARGC1A in adaptive thermogenesis.

Adipose Tissue↗

The pre-immune variable kappa repertoire of swine is selectively generated from certain subfamilies of Vkappa2 and one Jkappa gene.

Combinatorial diversity is highly restricted during formation of the pre-immune heavy chain repertoire of swine, raising the question of whether the same is true for the pre-immune light chain repertoire. Before addressing this question, we first used competitive PCR to show that kappa and lambda light chains in swine are equally expressed in mature B cells similar to the situation in humans but alike that in other studied Ungulates. This justified efforts to examine the repertoire of both light chain types. These studies also revealed that lambda is preferentially expressed at sites of B cells lymphogenesis, perhaps because of the use of a surrogate light chain containing lambda5. Data are presented here on >100 VkappaJkappa-containing transcripts and approximately 180 genomic Vkappa genes to show that >90% of the pre-immune repertoire is generated from three subfamilies of IGKV2 genes and one of five Jkappa segments. The kappa locus contains >or=50 IGKV2 genes belonging to at least five subfamilies and an undetermined but perhaps equal number of IGKV1 genes. The porcine IGKV1 and IGKV2 genes share 87% sequence similarity with their human counterparts and Jkappa1 through Jkappa5 share sequence and organizational homology with those in sheep, horse, human and mouse. Swine have a single Ckappa gene. These findings contrast with those from rodents and primates but are reminiscent of those on the pre-immune heavy chain repertoire of swine in that it is generated using a relatively restricted number of gene segments. These restricted pre-immune repertoires may reflect the minimal exposure of the fetus to maternal factors and environmental antigens. The significance for swine immunology of characterizing the pre-immune repertoire is discussed.

Amino Acid Sequence↗

A cDNA macroarray resource for gene expression profiling in ruminant tissues involved in reproduction and production (milk and beef) traits.

cDNA arrays have proven to be useful tools to screen gene expression in many animal species including livestock species. A collaborative program was launched to construct a ruminant cDNA collection, representative of three tissues: Muscle, Embryo and Mammary gland, named MEM. This collection gathers clones mainly arising from 3 non-normalised cDNA libraries: a directed bovine muscle library, a 14-day-old bovine embryo library and a goat lactating mammary library. It is made up of 1896 clones (637 muscle, 882 embryo and 377 mammary cDNAs), selected after sequencing and bioinformatic analyses. Amplification products yielded from these clones as well as controls were printed onto Nylon membranes to generate macroarrays. Hybridisation with relevant cDNA targets allowed checking the location of about 50 cDNAs and the specificity of each sub-set of the repertoire. Macroarrays were hybridised with radiolabelled cDNA complex targets from five different tissues (muscle, embryo, mammary gland, adipose tissue and oocyte). Both somatic and germinal complex targets gave valid hybridisation signals with 45 to 80% of the printed probes. This specific cDNA collection now provides a powerful tool for transcriptomic studies with the ultimate objective to better understand physiological and metabolic functions in ruminants. It will be subsequently included into a forthcoming larger collection.

Animals↗

A case of intersexuality in pigs associated with a de novo paracentric inversion 9 (p1.2; p2.2).

In several mammalian species, genetic defects can be responsible for the interruption of and/or the deviation from the sequential steps of normal gonadal differentiation, leading to a sex-reversal syndrome. In pigs, female-to-male sex-reversal conditions are particularly frequent, but their aetiologies remain unclear. Chromosomal abnormalities that co-occur with sex-reversal disorders can be useful in the identification of loci containing responsible or susceptibility genes. This report describes a female-to-male SRY-negative intersex pig with a de novo paracentric inversion of the short arm of one chromosome 9 (p1.2; p2.2). We have fine mapped the proximal chromosomal breakpoint of this rearrangement because it corresponded to a region potentially involved in the pig intersexuality. Fluorescent in situ hybridization (FISH) experiments carried out with Bacterial Artificial Chromosome (BAC) clones located within the critical region defined by genetic linkage analysis and ordered on the porcine RH map allowed us to locate the proximal breakpoint between markers SW2571 and SW539. Further investigations are currently in progress to find new markers inside this interval, in order to determine the BAC in which the break occurred.

Animals↗

Mapping of equine potassium chloride co-transporter (SLC12A4) and amino acid transporter (SLC7A10) and preliminary studies on associations between SNPs from SLC12A4, SLC7A10 and SLC7A9 and osmotic fragility of erythrocytes.

Consensus DNA sequences from human, mouse and/or rat were used to design oligonucleotide primers for equine homologues of exons 16, 17 and 20-23 of potassium chloride co-transporter (SLC12A4) and exons 10, 11 and 3, 4, respectively, for two amino acid transporters (SLC7A10 and SLC7A9). DNA sequences of the PCR products showed high sequence identity to these regions. Equine BAC clones were obtained for SLC12A4 and SLC7A10 and mapped to equine chromosomes ECA3p13 and ECA10p15, respectively, by fluorescence in situ hybridization (FISH). Several single nucleotide polymorphisms (SNP) were found. Substitutions of A/G were found within exon 17 of SLC12A4, within intron 11 of SLC7A10 and within intron 3 of SLC7A9. The SNP associated with SLC7A10 and SLC7A9 were sufficiently polymorphic to investigate associations with erythrocyte fragility among a group of 20 thoroughbred horses. A non-parametric rank-sum test showed a weak association between erythrocyte fragility and the SNP associated with SLC7A10 (P < 0.05).

Amino Acid Sequence↗

Fourteen chromosomal localizations and an update of the cytogenetic map of the rabbit.

In order to improve the informativeness of the cytogenetic map of the rabbit genome, fourteen markers were regionally mapped to individual chromosomes. The localizations comprise eleven gene loci (PRLR, GHR, HK1, ACE, TF, 18S+28S rDNA, CYP2C4, PMP2, TCRB, ALOX15 and MT1) and three microsatellite loci (Sat13, Sol33 and D1Utr6). Five of the genes contain known microsatellite sequences. To achieve these localizations, homologous and heterologous small insert clones, and clones from a rabbit Bacterial Artificial Chromosome (BAC) library were used as probes for fluorescence in situ hybridization experiments. Results indicate that especially BAC clones are a valuable tool for cytogenetic mapping. Some of the genes were selected for mapping on the basis of human- rabbit comparative painting data, to achieve localizations on gene-poor rabbit chromosomes. Our data are, in general, in agreement with the human-rabbit comparative painting data. By mapping microsatellite sequences that have also been used in linkage studies, links are provided between the genetic and physical maps of the rabbit genome. Linkage groups I, VI and XI could be assigned to chromosomes 1, 5 and 3 respectively. Moreover, in this paper we give an overview of the current status of the rabbit cytogenetic map. This map now comprises 62 physically mapped genes, which are scattered over all autosomes, except chromosome 2, and the X chromosome.

Animals↗

Integration of porcine chromosome 13 maps.

In order to expand the comparative map between human chromosome 3 (HSA3) and porcine chromosome 13 (SSC13), seven genes from HSA3 were mapped on SSC13 by fluorescence in situ hybridisation (FISH), viz. ACAA1, ACPP, B4GALT4, LTF, MYLK, PDHB and RARB. With a view to integrating this expanded comparative map with the existing SSC13 linkage map, we used the INRA-University of Minnesota porcine Radiation Hybrid panel (IMpRH) to localize more precisely and to order 15 genes on the SSC13 map, viz. ACPP, ADCY5, APOD, BCHE, CD86, DRD3, GAP43, PCCB, RAF1, RHO, SI, TF, TFRC, TOP2B and ZNF148. In this way, we were able to create an integrated map, containing 38 type I and 81 type II markers, by correlating the linkage, radiation hybrid (RH) and cytogenetic maps of SSC13. This integrated map will give us the opportunity to take maximal advantage of the comparative mapping strategy for positional candidate cloning of genes responsible for economically important traits.

Animals↗

Effect of time interval from insemination to first cleavage on the developmental characteristics, sex ratio and pregnancy rate after transfer of bovine embryos.

In vitro produced bovine zygotes show substantial variation in the time required to complete the first cell cycle and in their in vitro development potential. A number of reports have highlighted the fact that the fastest developing embryos in vitro are most likely to be comparable with their in vivo counterparts. At 24 h after IVF, presumptive zygotes were cultured in droplets of synthetic oviduct fluid medium. Droplets were examined at regular intervals and all cleaved embryos at each time point were transferred into new droplets and cultured separately for the duration of the experiment. All uncleaved zygotes were returned to the incubator and re-examined at the successive time points until 48 h after insemination, at which time the remaining uncleaved oocytes were retained as a group. A representative number of day 7 blastocysts from zygotes that had cleaved by 30 or 36 h were transferred to synchronized recipients and pregnancy was diagnosed by ultrasonography at day 35. Glucose and glutamine metabolism was examined in zygotes and blastocysts and compared retrospectively with time of first cleavage. A representative number of blastocysts from each of the cleavage groups was sexed using PCR. Data were analysed by chi-squared and regression analysis. Development to the blastocyst stage decreased as the time from insemination to first cleavage increased (r = 0.97, P < 0.03). There was no difference in blastocyst hatching, number of blastocyst cells or pregnancy rate between the 30 and 36 h groups. The overall sex ratio was 62% males (n = 258, P < 0.0001) and was not different in the 30 and 36 h groups (61%, n = 155 versus 63%, n = 95, respectively). These results indicate that although time of first cleavage has a major influence on the probability of an embryo developing to the blastocyst stage, once that stage is attained, subsequent developmental characteristics are unrelated to the time of first cleavage.

Animals↗

Comparative cytogenetic mapping reveals chromosome rearrangements between the X chromosomes of two closely related mammalian species (cattle and goats).

Cytogenetic localization of 24 BACs containing type I (genes and ESTs) and type II (microsatellites) markers were used to construct cytogenetic maps of caprine (CHI) and bovine (BTA) X chromosomes. Comparison of these two maps revealed that the distal region of the goat X long arm (CHI Xq38-->q42) was located inside the bovine X chromosome, between PGK1 (BTA Xq25) and DVEPC137 (BTA Xq12). The marker order was globally conserved without any pericentric inversion, as previously postulated in the literature. The caprine centromere was found between DVEPC053 and DVEPC102 (belonging to the same band in the bovine X: BTA Xq41), whereas the bovine centromere was between DVEPC076 and DVEPC132, belonging to the same region of the caprine X chromosome (CHI Xq31-->q33). The pseudoautosomal region was situated at the tip of the bovine X long arm and on the tiny short arm of the caprine X chromosome. In the non-pseudoautosomal (NPA) region, the synteny of coding sequences was well conserved between the human species and the two ruminant species, but the gene order was dramatically divergent. It is suggested that the 24 BACs of this study could constitute a new tool to measure phylogenetic distances between different mammalian species by comparing chromosome rearrangements inside the NPA region of the X.

Animals↗

Isolation of Y chromosome-specific microsatellites in the horse and cross-species amplification in the genus Equus.

Y chromosome polymorphisms such as microsatellites or single nucleotide polymorphisms represent a paternal counterpart to mitochondrial DNA (mtDNA) for evolutionary and phylogeographic studies. The use of Y chromosome haplotyping in natural populations of species other than humans is still hindered by the lack of sequence information necessary for polymorphism screening. Here we used representational difference analysis (RDA) followed by a screen of a bacterial artificial chromosome (BAC) library for repetitive sequences to obtain polymorphic Y-chromosomal markers. The procedure was performed for the domestic horse (Equus caballus) and we report the first six Y-chromosomal microsatellite markers for this species. Three markers were also useful for haplotyping taxa of the zebra/ass lineage. Y-chromosomal microsatellite markers show a single haplotype in the domestic horse, whereas notable variation has been observed in the other members of the genus Equus.

Alleles↗

Specific cytogenetic labeling of bovine spermatozoa bearing X or Y chromosomes using fluorescent in situ hybridization (FISH).

X and Y specific probes were identified in order to apply the fluorescent in situ hybridization (FISH) technique to bovine spermatozoa. For Y chromosome detection, the BRY4a repetitive probe, covering three quarters of the chromosome, was used. For X chromosome detection, a goat Bacterial Artificial Chromosome (BAC) specific to the X chromosome of bovine and goats and giving a strong FISH signal was used. Each probe labeled roughly 45% of sperm cells. The hybridization method will be useful for evaluating the ratio of X- and Y- bearing spermatozoa in a sperm sample and consequently can be used to evaluate the efficiency of sperm sorting by different techniques such as flow cytometry.

Animals↗