Genes in horses are segments of DNA that encode the biological instructions necessary for the development, functioning, and reproduction of equine species. These genetic sequences influence a wide range of traits, including coat color, speed, endurance, and susceptibility to diseases. Genetic research in horses focuses on identifying specific genes and genetic markers associated with these traits, as well as understanding the inheritance patterns and genetic diversity within and between horse breeds. Studies in equine genetics contribute to breeding programs, disease prevention strategies, and the overall understanding of horse biology. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, function, and implications of genes in equine health and performance.
Park KD, Kim H, Hwang JY, Lee CK, Do KT, Kim HS, Yang YM, Kwon YJ, Kim J, Kim HJ, Song KD, Oh JD, Kim H, Cho BW, Cho S, Lee HK.Copy number variations (CNVs), important genetic factors for study of human diseases, may have as large of an effect on phenotype as do single nucleotide polymorphisms. Indeed, it is widely accepted that CNVs are associated with differential disease susceptibility. However, the relationships between CNVs and gene expression have not been characterized in the horse. In this study, we investigated the effects of copy number deletion in the blood and muscle transcriptomes of Thoroughbred racing horses. We identified a total of 1,246 CNVs of deletion polymorphisms using DNA re-sequencing data from...
Esteves CL, Sharma R, Dawson L, Taylor SE, Pearson G, Keen JA, McDonald K, Aurich C, Donadeu FX.Expression of several putative markers of pluripotency (OCT4, SOX2, NANOG, LIN28A, REX1, DNMT3B and TERT) was examined in a range of equine tissues, including early embryos, induced pluripotent stem cells (iPSCs), testis, adipose- and bone marrow-derived mesenchymal stromal cells (MSCs), and keratinocytes. Transcript levels of all markers were highest in embryos and iPSCs and, except for SOX2, were very low or undetectable in keratinocytes. Mean expression levels of all markers were lower in testis than in embryos or iPSCs and, except for DNMT3B, were higher in testis than in MSCs. Expression ...
Equine germplasm bank management involves not only the conservation and use of semen doses, in addition it can also be a resource to study stallion semen quality and after thawing semen properties for reproductive purposes. A possible criterion to measure quality may be based on differential gene expression of loci involved during spermatogenesis and sperm quality maturation. The rapid degradation of sperm after thawing affects the integrity and availability of RNA. In this study we have analyzed genes expressed in equine cryopreserved sperm, which provided an adequate amplification, specifici...
Petersen JL, Valberg SJ, Mickelson JR, McCue ME.Two variants in the equine myostatin gene (MSTN), including a T/C SNP in the first intron and a 227-bp SINE insertion in the promoter, are associated with muscle fiber type proportions in the Quarter Horse (QH) and with the prediction of race distance propensity in the Thoroughbred (TB). Genotypes from these loci, along with 18 additional variants surrounding MSTN, were examined in 301 horses of 14 breeds to evaluate haplotype relationships and diversity. The C allele of intron 1 was found in 12 of 14 breeds at a frequency of 0.27; the SINE was observed in five breeds, but common in only the T...
Abitbol M, Legrand R, Tiret L.The seven donkey breeds recognised by the French studbook are characterised by few coat colours: black, bay and grey. Normand bay donkeys seldom give birth to red foals, a colour more commonly seen and recognised in American miniature donkeys. Red resembles the equine chestnut colour, previously attributed to a mutation in the melanocortin 1 receptor gene (MC1R). We used a panel of 124 donkeys to identify a recessive missense c.629T>C variant in MC1R that showed a perfect association with the red coat colour. This variant leads to a methionine to threonine substitution at position 210 in th...
Leise BS, Watts MR, Roy S, Yilmaz AS, Alder H, Belknap JK.Dysadhesion of laminar basal epithelial cells (LBECs) from the underlying dermis is the central event leading to structural failure in equine laminitis. Although many studies of sepsis-related laminitis have reported multiple events occurring throughout the lamellar tissue, there is minimal information regarding signalling events occurring specifically in LBECs. Objective: To determine signalling events in the LBECs during the early stages of carbohydrate-induced laminitis. Methods: Experimental study. Methods: Eight horses were given an overload of carbohydrate (CHO) consisting of corn starch...
Wong A, Ghassemi E, Yellowley CE.The intermediate filament protein nestin is used as a marker for neural stem cells, and its expression is inversely correlated with cellular differentiation. More recently, nestin expression has also been described in other cell types including multipotential mesenchymal stromal cells (MSCs). In this study, we examined the expression of nestin in equine, canine and human bone marrow-derived MSCs undergoing osteogenic differentiation, to determine whether nestin levels were attenuated as the cells acquired a more mature phenotype. In addition, the expression of nestin may be under the influence...
Jäderkvist K, Andersson LS, Johansson AM, Árnason T, Mikko S, Eriksson S, Andersson L, Lindgren G.In a previous study it was shown that a nonsense mutation in the DMRT3 gene alters the pattern of locomotion in horses and that this mutation has a strong positive impact on trotting performance of Standardbreds. One aim of this study was to test if racing performance and trotting technique in the Nordic (Coldblood) trotters are also influenced by the DMRT3 genotype. Another aim was to further investigate the effect of the mutation on performance in Standardbreds, by using a within-family analysis and genotype-phenotype correlations in a larger horse material than in the previous study. We gen...
Kristjansson T, Bjornsdottir S, Sigurdsson A, Andersson LS, Lindgren G, Helyar SJ, Klonowski AM, Arnason T.A nonsense mutation in DMRT3 ('Gait keeper' mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild-type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the freq...
Schmiedel J, Falgenhauer L, Domann E, Bauerfeind R, Prenger-Berninghoff E, Imirzalioglu C, Chakraborty T.Multiresistant Gram-negative bacteria producing extended-spectrum β-lactamases (ESBLs) are an emerging problem in human and veterinary medicine. This study focused on comparative molecular characterization of β-lactamase and ESBL-producing Enterobacteriaceae isolates from central Hesse in Germany. Isolates originated from humans, companion animals (dogs and cats) and horses. Results: In this study 153 (83.6%) of the human isolates (n = 183) and 163 (91.6%) of the animal isolates (n = 178) were confirmed as ESBL producers by PCR and subsequent sequencing of the PCR amplicons. Predomin...
BMC research notesJuly 12, 2014
Volume 7 448 doi: 10.1186/1756-0500-7-448
Boukharta M, Zakham F, Touil N, Elharrak M, Ennaji MM.The equine influenza (EI) is an infectious and contagious disease of the upper respiratory tract of horses. Two outbreaks were notified in Morocco during 1997 and 2004 respectively in Nador and Essaouira. The aims of the present study concern the amino acids sequences comparison with reference strain A/equine/Miami/1963(H3N8) of the HA2 subunit including the cleavage site of three equine influenza viruses (H3N8) isolated in Morocco: A/equine/Nador/1/1997(H3N8), A/equine/Essaouira/2/2004 (H3N8) and A/equine/Essaouira/3/2004 (H3N8). Results: The obtained results demonstrated that the substitutio...
Ing NH, Forrest DW, Riggs PK, Loux S, Love CC, Brinsko SP, Varner DD, Welsh TH.In rodents, livestock and primate species, a single dose of the synthetic glucocorticoid dexamethasone acutely lowers testosterone biosynthesis. To determine the mechanism of decreased testosterone biosynthesis, stallions were treated with 0.1mg/kg dexamethasone 12h prior to castration. Dexamethasone decreased serum concentrations of testosterone by 60% compared to saline-treated control stallions. Transcriptome analyses (microarrays, northern blots and quantitative PCR) of testes discovered that dexamethasone treatment decreased concentrations of glucocorticoid receptor alpha (NR3C1), alpha a...
Szczerba-Turek A, Bancerz-Kisiel A, Lipczyńska K, Siemionek J, Raś A, Platt-Samoraj A, Szweda W.The aim of the study was to evaluate a novel diagnostic scheme which combines quantitative PCR and High-Resolution Melting (qPCR-HRM) curve analysis for rapid differentiation based on E5 partial CDS of bovine papillomavirus type 1 or 2 (BPV-1 or BPV-2), and to perform a phylogenetic analysis of the complete CDS of the E5 gene of BPV detected in equine sarcoids. Samples of 38 skin lesions obtained from 27 horses were collected for molecular examinations. All lesions were clinically diagnosed as sarcoids, but results of histopathological examinations did not always corroborate the clinical diagn...
Metzger J, Tonda R, Beltran S, Agueda L, Gut M, Distl O.Domestication has shaped the horse and lead to a group of many different types. Some have been under strong human selection while others developed in close relationship with nature. The aim of our study was to perform next generation sequencing of breed and non-breed horses to provide an insight into genetic influences on selective forces. Results: Whole genome sequencing of five horses of four different populations revealed 10,193,421 single nucleotide polymorphisms (SNPs) and 1,361,948 insertion/deletion polymorphisms (indels). In comparison to horse variant databases and previous reports, w...
Finno CJ, Bannasch DL.Genome sequencing of the domestic horse and subsequent advancements in the field of equine genomics have led to an explosion in the development of tools for mapping traits and diseases and evaluating gene expression. The objective of this review is to discuss the current progress in the field of equine genomics, with specific emphasis on assembly and analysis of the reference sequence and subsequent sequencing of a Quarter Horse mare; the genomic tools currently available to researchers and their implications in genomic investigations in the horse; the genomics of Mendelian and non-Mendelian t...
Gim JA, Ayarpadikannan S, Eo J, Kwon YJ, Choi Y, Lee HK, Park KD, Yang YM, Cho BW, Kim HS.Physical exercise induces gene expression changes that trigger glucose metabolism pathways in organisms. In the present study, we monitored the expression levels of LDHA (lactate dehydrogenase) and GYS1 (glycogen synthase 1) in the blood, to confirm the roles of these genes in exercise physiology. LDHA and GYS1 are related to glucose metabolism and fatigue recovery, and these processes could elicit economically important traits in racehorses. We collected blood samples from three retired thoroughbred racehorses, pre-exercise and immediately after 30 min of exercise. We extracted total RNA and ...
Morrison PK, Bing C, Harris PA, Maltin CA, Grove-White D, Argo CM.Obesity, a major concern for equine welfare, is highly prevalent in the leisure horse population. Skeletal-muscle and adipose tissues are important determinants of maintenance energy requirements. The myostatin and perilipin pathways play key roles in the regulation of muscle mass and lipolysis respectively and have both been associated with obesity predisposition in other mammalian species. High quality samples, suitable for molecular biology, are an essential prerequisite for detailed investigations of gene and protein expression. Hence, this study has evaluated a) the post-mortem stability ...
Labitzke D, Sieme H, Martinsson G, Distl O.The objectives of this study were to show whether semen traits of 30 Hanoverian stallions regularly used in AI may be useful for breeding purposes. Semen characteristics were studied using 15 149 ejaculates from 30 Hanoverian stallions of the State Stud Celle of Lower Saxony. Semen samples were collected between 2005 and 2009. Traits analysed were gel-free volume, sperm concentration, total and motile sperm number and progressive motility. A linear multivariate animal model was employed to estimate heritabilities and permanent environmental variances for stallions. The same model was used to p...
Huang J, Zhao Y, Shiraigol W, Li B, Bai D, Ye W, Daidiikhuu D, Yang L, Jin B, Zhao Q, Gao Y, Wu J, Bao W, Li A, Zhang Y, Han H, Bai H, Bao Y, Zhao L....Karyotypic diversification is more prominent in Equus species than in other mammals. Here, using next generation sequencing technology, we generated and de novo assembled quality genomes sequences for a male wild horse (Przewalski's horse) and a male domestic horse (Mongolian horse), with about 93-fold and 91-fold coverage, respectively. Portion of Y chromosome from wild horse assemblies (3 M bp) and Mongolian horse (2 M bp) were also sequenced and de novo assembled. We confirmed a Robertsonian translocation event through the wild horse's chromosomes 23 and 24, which contained sequences th...
van den Top JG, Harkema L, Lange C, Ensink JM, van de Lest CH, Barneveld A, van Weeren PR, Gröne A, Martens A.Equine penile and preputial squamous cell carcinoma (SCC) is a potentially lethal disease of which little is known regarding the relationship between tumour characteristics and prognosis. Objective: To assess the relationship between tumour differentiation grade (tumour subtype), presence of papillomaviruses, expression of viral genes (E2, E6, L1), nuclear proteins p53 and Ki67 and metastasis in equine penile and preputial SCC and to assess the relationship of tumour subtype, presence of papillomavirus type 2, p53 and Ki67 with survival. Methods: Retrospective case-control study using archived...
Sayasith K, Sirois J.The interaction between stromal cell-derived factor-1 (SDF1) and chemokine CXC motif receptor 4 (CXCR4) has been implicated in leukocyte attraction, tissue remodeling and angiogenesis. The objective of the present study was to characterize the expression and regulation of SDF1 and CXCR4 in equine follicles during the ovulatory process. Equine preovulatory follicles were isolated during estrus 0-39h after hCG treatment. Follicle wall preparations (theca interna with attached granulosa cells) and isolated preparations of granulosa cells and theca interna were obtained, and total RNA extracts wer...
Côté O, Clark ME, Viel L, Labbé G, Seah SY, Khan MA, Douda DN, Palaniyar N, Bienzle D.Secretoglobin family 1A member 1 (SCGB 1A1) is a small protein mainly secreted by mucosal epithelial cells of the lungs and uterus. SCGB 1A1, also known as club (Clara) cell secretory protein, represents a major constituent of airway surface fluid. The protein has anti-inflammatory properties, and its concentration is reduced in equine recurrent airway obstruction (RAO) and human asthma. RAO is characterized by reversible airway obstruction, bronchoconstriction and neutrophilic inflammation. Direct effects of SCGB 1A1 on neutrophil functions are unknown. We have recently identified that the SC...
Tallmadge RL, Tseng CT, Felippe MJ.To further studies of neonatal immune responses to pathogens and vaccination, we investigated the dynamics of B lymphocyte development and immunoglobulin (Ig) gene diversity. Previously we demonstrated that equine fetal Ig VDJ sequences exhibit combinatorial and junctional diversity levels comparable to those of adult Ig VDJ sequences. Herein, RACE clones from fetal, neonatal, foal, and adult lymphoid tissue were assessed for Ig lambda light chain combinatorial, junctional, and sequence diversity. Remarkably, more lambda variable genes (IGLV) were used during fetal life than later stages and I...
Nieri-Bastos FA, Lopes MG, Cançado PH, Rossa GA, Faccini JL, Gennari SM, Labruna MB.Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the Cerrado biome (state of Piauí) in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR) targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB ge...
Azab W, Harman R, Miller D, Tallmadge R, Frampton AR, Antczak DF, Osterrieder N.Equid herpesvirus type 1 (EHV-1) was shown to use an unusual receptor for cellular entry - MHC-I molecules. Here, we demonstrated that the closely related EHV, EHV-4, also uses this strategy for cellular invasion, both in equine cells in culture and in the heterologous, non-permissive murine mastocytoma cell line (P815) after stable transfection with horse MHC-I genes. Using a panel of P815 cell lines transfected with individual horse MHC-I genes, we provided support for the hypothesis that EHV-1 and EHV-4 target classical polymorphic MHC-I molecules as viral entry receptors. All known equine ...
de Ruijter-Villani M, van Tol HT, Stout TA.Endometrial oxytocin receptors (OXTR) and prostaglandin-endoperoxide synthase 2 (PTGS2) are central components of the luteolytic pathway in cyclic mares, and their suppression is thought to be critical to luteal maintenance during early pregnancy. We examined the effect of pregnancy on endometrial expression of potential regulators of prostaglandin (PG) F2α secretion in mares. Expression of the nuclear progesterone receptor and oestrogen receptor ERα was high during oestrus, and depressed when progesterone was elevated; the opposite applied to the membrane progesterone receptor. PTGS2 was up...
Whitworth DJ, Ovchinnikov DA, Sun J, Fortuna PR, Wolvetang EJ.In this study we have reprogrammed dermal fibroblasts from an adult female horse into equine induced pluripotent stem cells (equiPSCs). These equiPSCs are dependent only on leukemia inhibitory factor (LIF), placing them in striking contrast to previously derived equiPSCs that have been shown to be co-dependent on both LIF and basic fibroblast growth factor (bFGF). These equiPSCs have a normal karyotype and have been maintained beyond 60 passages. They possess alkaline phosphatase activity and express eqNANOG, eqOCT4, and eqTERT mRNA. Immunocytochemistry confirmed that they produce NANOG, REX1,...
Murphy BA, Wagner AL, McGlynn OF, Kharazyan F, Browne JA, Elliott JA.Circadian rhythms are endogenously generated 24-h oscillations that coordinate numerous aspects of mammalian physiology, metabolism and behaviour. The existence of a molecular circadian clock in equine skeletal muscle has previously been demonstrated. This study investigates how the circadian 24-h expression of exercise-relevant genes in skeletal muscle is influenced by a regular exercise regime. Mid-gluteal, percutaneous muscle biopsies were obtained over a 24-h period from six Thoroughbred mares before and after an 8-week exercise programme. Real-time qPCR assays were used to assess the expr...
Park W, Kim J, Kim HJ, Choi J, Park JW, Cho HW, Kim BW, Park MH, Shin TS, Cho SK, Park JK, Kim H, Hwang JY, Lee CK, Lee HK, Cho S, Cho BW.Previous studies of horse RNA-seq were performed by mapping sequence reads to the reference genome during transcriptome analysis. However in this study, we focused on two main ideas. First, differentially expressed genes (DEGs) were identified by de novo-based analysis (DBA) in RNA-seq data from six Thoroughbreds before and after exercise, here-after referred to as "de novo unique differentially expressed genes" (DUDEG). Second, by integrating both conventional DEGs and genes identified as being selected for during domestication of Thoroughbred and Jeju pony from whole genome re-sequencing (WG...
Gulati BR, Kumar R, Mohanty N, Kumar P, Somasundaram RK, Yadav PS.Tendon injuries are common in race horses, and mesenchymal stem cells (MSCs) isolated from adult and foetal tissue have been used for tendon regeneration. In the present study, we evaluated equine amniotic fluid (AF) as a source of MSCs and standardised methodology and markers for their in vitro tenogenic differentiation. Plastic-adherent colonies were isolated from 12 of 20 AF samples by day 6 after seeding and 70-80% cell confluency was reached by day 17. These cells expressed mesenchymal surface markers [cluster of differentiation (CD)73, CD90 and CD105] by reverse transcription (RT)-polyme...
Dini P, Kalbfleisch T, Uribe-Salazar JM, Carossino M, Ali HE, Loux SC, Esteller-Vico A, Norris JK, Anand L, Scoggin KE, Rodriguez Lopez CM, Breen J....Most autosomal genes in the placenta show a biallelic expression pattern. However, some genes exhibit allele-specific transcription depending on the parental origin of the chromosomes on which the copy of the gene resides. Parentally expressed genes are involved in the reciprocal interaction between maternal and paternal genes, coordinating the allocation of resources between fetus and mother. One of the main challenges of studying parental-specific allelic expression (allele-specific expression [ASE]) in the placenta is the maternal cellular remnant at the fetomaternal interface. Horses () ha...
Won SY, Kim YC, Do K, Jeong BH.Prion disease is a fatal neurodegenerative disorder caused by a deleterious prion protein (PrP). However, prion disease has not been reported in horses during outbreaks of transmissible spongiform encephalopathies (TSEs) in various animals in the UK. In previous studies, single nucleotide polymorphisms (SNPs) in the prion protein gene () have been significantly associated with susceptibility to prion disease, and strong linkage disequilibrium (LD) between and prion-like protein gene () SNPs has been identified in prion disease-susceptible species. On the other hand, weak LD values have been r...
Druml T, Brem G, Velie B, Lindgren G, Horna M, Ricard A, Grilz-Seger G.In horses, the autoimmune disease vitiligo is characterized by the loss of melanocytes and results in patchy depigmentation of the skin around the eyes, muzzle and the perianal region. Vitiligo-like depigmentation occurs predominantly in horses displaying the grey coat colour and is observed at a prevalence level of 26.0-67.0% in grey horses compared with only 0.8-3.5% in non-grey horses. While the polygenetic background of this complex disease is well documented in humans, the underlying candidate genes for this skin disorder in horses remain unknown. In this study we aim to perform a genome-...
Hellman S, Hjertner B, Morein B, Fossum C.The immunomodulatory effect of a new particulate adjuvant, G3, alone or in combination with agonists to TLR2/1 or TLR5 was evaluated in cultures of equine PBMC. Exposure to the G3 adjuvant up-regulated genes encoding IFN-γ, IL-1β, IL-6, IL-8, IL-12p40 and IL-23p19 in the majority of the horses tested, indicating that the G3 adjuvant induced a pro-inflammatory and Th1 dominated profile. In accordance, genes encoding IL-13, IL-4, IL-10 and TGF-β remained unaffected and genes encoding IFN-α, IL-17A and TNF-α were only occasionally and weakly induced. The two TLR agonists Pam3CSK4 (TLR2/1) an...
de Castro RVG, Pieri NCG, Fantinato Neto P, Grizendi BM, Dória RGS, Meirelles FV, Smith LC, Garcia JM, Bressan FF.The cellular reprogramming into pluripotency is influenced by external and internal cellular factors, such as culture conditions (e.g., environmental oxygen concentration), and the aging process. Herein, we aimed to generate and maintain equine iPSCs (eiPSCs) derived from fibroblasts of a horse older than 20 years and to evaluate the effect of different levels of oxygen tension (atmospheric 20% O, 5% O, or 20% to 5% O) on these cells. Fibroblasts were reprogrammed, and putative eiPSCs were positive for positive alkaline phosphatase detection; they were positive for pluripotency-related genes ...
Jemmerson R.To gain a better understanding of the diversity of epitopes on a protein, the specificities of 103 monoclonal antibodies to a model antigen, horse cytochrome c(cyt c), were analyzed. The antibodies were generated in in vitro monoclonal, secondary antibody responses against horse cyt c coupled to hemocyanin in splenic fragment cultures. For this assay, horse cyt c-primed murine B lymphocytes were transferred to irradiated, hemocyanin-primed recipients. A panel of seven mammalian cyts c differing at one to six residues out of 104 and cyanogen bromide-cleaved fragments of horse cyt c containing r...
Hines R, Sorensen BR, Shea MA, Maury W.Binding of the transcription factor PU.1 to its DNA binding motif regulates the expression of a number of B-cell- and myeloid-specific genes. The long terminal repeat (LTR) of macrophage-tropic strains of equine infectious anemia virus (EIAV) contains three PU.1 binding sites, namely an invariant promoter-proximal site as well as two upstream sites. We have previously shown that these sites are important for EIAV LTR activity in primary macrophages (W. Maury, J. Virol. 68:6270-6279, 1994). Since the sequences present in these three binding motifs are not identical, we sought to determine the r...
Lichtenstein DL, Craigo JK, Leroux C, Rushlow KE, Cook RF, Cook SJ, Issel CJ, Montelaro RC.The long terminal repeat (LTR) is reported to be one of the most variable portions of the equine infectious anemia virus (EIAV) genome. To date, however, no information is available on the effects of observed sequence variations on viral replication properties, despite a widespread assumption of the biological importance of EIAV LTR variation. EIAV LTR sequence variability is confined mostly to a small portion of the enhancer within the U3 segment of the LTR. Analysis of published EIAV LTR sequences revealed six different types of LTR based on the pattern of putative transcription factor motif...
Perelygin AA, Zharkikh AA, Astakhova NM, Lear TL, Brinton MA.Chemokine receptors (CCRs) play an essential role in the initiation of an innate immune host response. Several of these receptors have been shown to modulate the outcome of viral infections. The recent availability of complete genome sequences from a number of species provides a unique opportunity to analyze the evolution of the CCR genes. A phylogenetic analysis revealed that the CCR2 gene evolved in concert with the paralogous CCR5 gene, but not with another paralogous gene, CCR3, in the opossum, platypus, rabbit, guinea pig, cat, and rodent lineages. In addition, evidence of concerted evolu...
Robles M, Peugnet P, Dubois C, Piumi F, Jouneau L, Bouchez O, Aubrière MC, Dahirel M, Aioun J, Wimel L, Couturier-Tarrade A, Chavatte-Palmer P.Feeding pregnant broodmares with cereal concentrates has been shown to increase maternal insulin resistance and affect foal metabolism in the short and long-term. These effects are likely to be mediated by the placenta. Here, we investigated feto-placental biometry and placental structure and function at term in mares fed with or without cereals concentrates. From 7 months of gestation, 22 multiparous mares were fed forage only (group F (n = 12)) or received forage and cracked barley (group B (n = 10)) until foaling. Foals and placentas were weighed and placental samples were collected...
Sun Y, MacLean AR, Aitken JD, Brown SM.Equine herpesvirus type 1 (EHV-1) gene 71 encodes a heavily O-glycosylated 192 kDa protein with no identified herpesvirus homologue. Isolation of a deletion mutant in gene 71 (ED71) demonstrated that its protein product is not essential in vitro. To investigate the role of the gene 71 protein in the virus life cycle, ED71 has been characterized in vitro in terms of cellular adsorption, penetration, egress and transmission compared to wild-type and revertant virus. ED71 virions adsorbed to cells less efficiently than wild-type and revertant virus with a consequential effect on virus penetration...
Howe DK.To accelerate genetic and molecular characterization of Sarcocystis neurona, the primary causative agent of equine protozoal myeloencephalitis (EPM), a sequencing project has been initiated that will generate approximately 7000-8000 expressed sequence tags (ESTs) from this apicomplexan parasite. Poly(A)(+) RNA was isolated from culture-derived S. neurona merozoites, and a cDNA library was constructed in a unidirectional lambda phage cloning vector. Sixty phage clones were randomly picked from the library, and the cDNA inserts were amplified from these clones using the T3 and T7 primers that fl...
Cieslak J, Wodas L, Borowska A, Pawlak P, Czyzak-Runowska G, Wojtowski J, Puppel K, Kuczynska B, Mackowski M.Genes encoding casein proteins are important candidates for milk composition traits in mammals. In the case of the domestic horse, our knowledge of casein genes is limited mainly to coding sequence variants. This study involved screening for polymorphism in 5'-flanking regions of four genes encoding equine caseins (CSN1S1, CSN1S2, CSN2, and CSN3) and making a preliminary assessment of their effect on the gene expression (on the mRNA and protein levels) and milk composition traits in selected horse breeds. Altogether, 23 polymorphisms (21 described previously SNPs and two novel InDels) were fou...
Page AE, Adam E, Arthur R, Barker V, Franklin F, Friedman R, Grande T, Hardy M, Howard B, Partridge E, Rutledge M, Scollay M, Stewart JC, Vale A....The ability to identify horses at risk for catastrophic injuries continues to be a pressing issue for the racing industry, especially given recent events in North America. Objective: Since most catastrophic injuries occur in areas of existing pathology and this pathology is likely to elicit an inflammatory response, it was hypothesised that analysis of messenger RNA (mRNA) expression would detect significant changes in select genes in horses at risk for a catastrophic injury. Methods: Prospective cohort study. Methods: Five racing jurisdictions across the United States participated in this stu...
Hill EW, Ryan DP, MacHugh DE.Variation at the myostatin (MSTN) gene locus has been shown to influence racing phenotypes in Thoroughbred horses, and in particular, early skeletal muscle development and the aptitude for racing at short distances. Specifically, a single nucleotide polymorphism (SNP) in the first intron of MSTN (g.66493737C/T) is highly predictive of best race distance among Flat racing Thoroughbreds: homozygous C/C horses are best suited to short distance races, heterozygous C/T horses are best suited to middle distance races, and homozygous T/T horses are best suited to longer distance races. Patent applica...
Melnick JL, Hampil B.This paper summarizes the results of the fourth part of a comprehensive programme undertaken by the WHO International Reference Centre for Enteroviruses and other laboratories for the testing of enterovirus equine antisera prepared for long-term use as reference antisera. The studies were designed to appraise the specificity of the immune serum of horses inoculated with prototype enteroviruses (coxsackievirus types A2, 4, 8, 10, 11, 14-16, 18-21, and 24, and echoviruses E21, 27, 30, 31, and 33). Tests for neutralizing antibody were performed against the homologous viruses and against available...
Green RD, Qureshi MA, Long JA, Burfening PJ, Hamernik DL.Agricultural animal research has been immensely successful over the past century in developing technology and methodologies that have dramatically enhanced production efficiency of the beef, dairy, swine, poultry, sheep, and aquaculture industries. In the past two decades, molecular biology has changed the face of agricultural animal research, primarily in the arena of genomics and the relatively new offshoot areas of functional genomics, proteomics, transcriptomics, metabolomics and metagenomics. Publication of genetic and physical genome maps in the past 15 years has given rise to the possib...
Maniego J, Pesko B, Habershon-Butcher J, Huggett J, Taylor P, Scarth J, Ryder E.Throughout the history of horse racing, doping techniques to suppress or enhance performance have expanded to match the technology available. The next frontier in doping, both in the equine and human sports areas, is predicted to be genetic manipulation; either by prohibited use of genome editing, or gene therapy via transgenes. By using massively-parallel sequencing via a two-step PCR method we can screen for multiple doping targets at once in pooled primer sets. This method has the advantages of high scalability through combinational indexing, and the use of reference standards with altered ...
Moyo NA, Marchi E, Steinbach F.Dendritic cells (DC) are the main immune mediators inducing primary immune responses. DC generated from monocytes (MoDC) are a model system to study the biology of DC in vitro, as they represent inflammatory DC in vivo. Previous studies on the generation of MoDC in horses indicated that there was no distinct difference between immature and mature DC and that the expression profile was distinctly different from humans, where CD206 is expressed on immature MoDC whereas CD83 is expressed on mature MoDC. Here we describe the kinetics of equine MoDC differentiation and activation, analysing both ph...
Charvat RA, Breitenbach JE, Ahn B, Zhang Y, O'Callaghan DJ.Defective interfering particles (DIP) of equine herpesvirus 1 (EHV-1) inhibit standard virus replication and mediate persistent infection. The DIP genome is comprised of only three genes: UL3, UL4, and a hybrid gene composed of portions of the IR4 (EICP22) and UL5 (EICP27) genes. The hybrid gene is important for DIP interference, but the function(s) of the UL3 and UL4 genes are unknown. Here, we show that UL4 is an early gene activated solely by the immediate early protein. The UL4 protein (UL4P) was detected at 4hours post-infection, was localized throughout the nucleus and cytoplasm, and was...
Ramery E, Fraipont A, Richard EA, Art T, Pirottin D, van Delm W, Bureau F, Lekeux P.Inflammatory airway disease (IAD) affects performance and well-being of horses. Diagnosis is primarily reached by bronchoalveolar lavage (BAL) cytology which is invasive and requires sedation. Objective: The purpose of this study was to identify differential gene expression in peripheral blood of horses with IAD using species-specific expression microarrays. Methods: Equine gene expression microarrays were used to investigate global mRNA expression in circulating leukocytes from healthy, IAD-affected, and low-performing Standardbred and endurance horses. Results: Nine genes in Standardbred and...
Yildirim AO, Lämmler Ch, Weiss R.Seven group B streptococcal cultures isolated from three horses reacted with group B-specific antiserum, were CAMP positive, pigmented and showed the typical biochemical properties of Streptococcus agalactiae. The identification could be confirmed by PCR amplification of the 16S rRNA gene and a subsequent RsaI restriction pattern typical for S. agalactiae. In addition, the isolates were identified by amplification of species specific parts of the 16S rRNA gene, the 16S-23S rRNA intergenic spacer region and by amplification of the CAMP-factor (cfb) gene. Six isolates could be classified as sero...
Heller MC, Jackson KA, Watson JL.Rhodococcus equi is a facultative intracellular bacterial pathogen of horses; infected foals develop pyogranulomatous pneumonia, however adult horses are largely unaffected. R. equi infects and proliferates within host macrophages and dendritic cells (DCs). DCs initiate the appropriate adaptive immune response, thereby playing a critical role in determining the outcome of infection. Our aim was to identify genes that are differentially expressed in R. equi infected monocyte-derived DCs (mdDCs). Peripheral blood monocytes from mares and foals were used to derive mdDCs by culturing with recombin...
Perelygin AA, Lear TL, Zharkikh AA, Brinton MA.Mammalian 2'-5' oligoadenylate (2-5A) synthetases are important mediators of the antiviral activity of interferons. Both human and mouse 2-5A synthetase gene families encode four forms of enzymes: small, medium, large and ubiquitin-like. In this study, the structures of four equine OAS genes were determined using DNA sequences derived from fifteen cDNA and four BAC clones. Composition of the equine OAS gene family is more similar to that of the human OAS family than the mouse Oas family. Two OAS-containing bovine BAC clones were identified in GenBank. Both equine and bovine BAC clones were phy...
Dube F, Hinas A, Roy S, Martin F, Åbrink M, Svärd S, Tydén E.The nematode Parascaris univalens is one of the most prevalent parasitic pathogens infecting horses but anthelmintic resistance undermines treatment approaches. The molecular mechanisms underlying drug activity and resistance remain poorly understood in this parasite since experimental in vitro models are lacking. The aim of this study was to evaluate the use of Caenorhabditis elegans as a model for P. univalens drug metabolism/resistance studies by a comparative gene expression approach after in vitro exposure to the anthelmintic drug ivermectin (IVM). Methods: Twelve adult P. univalens worms...
Godard S, Vaiman A, Schibler L, Mariat D, Vaiman D, Cribiu EP, Guérin G.The purpose of this study was to increase the number of genes assigned by in situ hybridization to equine chromosomes and thus the number of links for comparative mapping with other species. Forty-four new sequences were added to the horse cytogenetic map by FISH mapping of BAC clones containing genes (35) or ESTs (9). Three approaches were developed: use of horse BAC clones screened with (i) horse EST primers, (ii) interspecific consensus intraexonic primers, and (iii) use of goat BAC containing genes previously localized on goat chromosomes. Present data suggest that the second approach is t...
Green JA, Xie S, Szafranska B, Gan X, Newman AG, McDowell K, Roberts RM.The pregnancy-associated glycoproteins (PAGs) are placental antigens that were initially characterized as pregnancy markers in the maternal circulation of domestic ruminant species. They are members of the aspartic proteinase gene family, having greatest sequence identity with pepsinogens. However, some are not capable of functioning as enzymes. The PAGs are associated with a large gene family within the Artiodactyla order (cattle, camels, pigs). So far, no members of this family have been characterized in species outside this order. This report describes the cloning and initial characterizati...
Echigoya Y, Sato T, Itou T, Endo H, Sakai T.The species-specific properties of LDH isozymes are essentially determined by M (muscle) and H (heart) subunit proteins encoded by the LDHA and LDHB genes, respectively. In the present study, we molecularly characterized the full-length equine lactate dehydrogenase A (eLDHA) and B (eLDHB) cDNAs. The eLDHA cDNA consisted of a 999-bp open reading frame (ORF), while the eLDHB and newly acquired bat LDHB consisted of a 1002-bp ORF, which is 3 bp shorter than the LDHB ORF of other registered mammals. The alignment of amino acid sequences showed that eLDHA acquired positively charged His 88 and 226,...
Herrera-Luna CV, Budik S, Aurich C.Glucocorticoids (GCs) are important mediators of the stress response and have been implicated in the function and regulation of testicular functions in different species. In many tissues, intracellular glucocorticoid activity is controlled by either or both of the two known isoforms of 11β-hydroxysteroid dehydrogenase (11βHSD) type 1 and 2, which interconvert active and inactive GCs. Little is known about the effects of stress on fertility in the equine species. The main objective of the present study was to investigate the expression of receptors for GCs and adrenocorticotropic hormone [ACT...
Thaker SR, Dutta SK, Adhya SL, Mattingly-Napier BL.A gene bank of Ehrlichia risticii was constructed in plasmid vector pUC13. Five clones representing discrete regions of the E. risticii genome were tested for their ability to hybridize specifically to E. risticii DNA. None of the clones cross-hybridized with Ehrlichia equi DNA, whereas four of these clones cross-hybridized with Ehrlichia canis and Ehrlichia sennetsu DNAs. However, one clone carrying a 1-kilobase HindIII fragment of E. risticii DNA failed to cross-react with the genomes of E. sennetsu, E. canis, and E. equi in dot blot hybridization assays. The sensitivity of this probe for th...
