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1.
J Chem Phys ; 139(21): 214307, 2013 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-24320380

RESUMO

The pure rotational spectrum of KSH (X(1)A') has been measured using millimeter-wave direct absorption and Fourier transform microwave (FTMW) techniques. This work is the first gas-phase experimental study of this molecule and includes spectroscopy of KSD as well. In the millimeter-wave system, KSH was synthesized in a DC discharge from a mixture of potassium vapor, H2S, and argon; a discharge-assisted laser ablation source, coupled with a supersonic jet expansion, was used to create the species in the FTMW instrument. Five and three rotational transitions in the range 3-57 GHz were recorded with the FTMW experiment for KSH and KSD, respectively, in the K(a) = 0 component; in these data, potassium quadrupole hyperfine structure was observed. Five to six transitions with K(a) = 0-5 were measured in the mm-wave region (260-300 GHz) for the two species. The presence of multiple asymmetry components in the mm-wave spectra indicates that KSH has a bent geometry, in analogy to other alkali hydrosulfides. The data were analyzed with an S-reduced asymmetric top Hamiltonian, and rotational, centrifugal distortion, and potassium electric quadrupole coupling constants were determined for both isotopolgues. The r0 geometry for KSH was calculated to be r(S-H) = 1.357(1) Å, r(K-S) = 2.806(1) Å, and θ(M-S-H) (°) = 95.0 (1). FTMW measurements were also carried out on LiSH and NaSH; metal electric quadrupole coupling constants were determined for comparison with KSH. In addition, ab initio computations of the structures and vibrational frequencies at the CCSD(T)/6-311++G(3df,2pd) and CCSD(T)/aug-cc-pVTZ levels of theory were performed for LiSH, NaSH, and KSH. Overall, experimental and computational data suggest that the metal-ligand bonding in KSH is a combination of electrostatic and covalent forces.

2.
J Anim Breed Genet ; 130(3): 227-35, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23679948

RESUMO

The potential future earnings and therefore value of Thoroughbred foals untested in the racing arena are calculated based on the performance of their forebears. Thus, lineage is of key importance. However, previous research indicates that maternally inherited mitochondrial DNA (mtDNA) does not correspond to maternal lineage according to recorded pedigree, casting doubt on the voracity of historic pedigrees. We analysed mtDNA of 296 Thoroughbred horses from 33 maternal lineages and identified an interesting trend. Subsequent to the founding of the Thoroughbred breed in the 16th century, well-populated maternal lineages were divided into sub-lineages. Only six in 10 of the Thoroughbreds sampled shared mitochondrial haplotype with other members of their maternal lineage, despite having a common maternal ancestor according to pedigree records. However, nine in 10 Thoroughbreds from the 103 sub-lineages sampled shared mtDNA with horses of their maternal pedigree sub-lineage. Thus, Thoroughbred maternal sub-lineage pedigree represents a more accurate breeding record than previously thought. Errors in pedigrees must have occurred largely, though, not exclusively, at sub-lineage foundation events, probably due to incomplete understanding of modes of inheritance in the past, where maternal sub-lineages were founded from individuals, related, but not by female descent.


Assuntos
DNA Mitocondrial/genética , Cavalos/genética , Mães , Linhagem , Esportes , Animais , Evolução Molecular , Feminino , Variação Genética/genética , Análise de Sequência de DNA
3.
Anim Genet ; 43(3): 340-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22486509

RESUMO

Changes in the inbreeding coefficient, F, in the Thoroughbred horse over the past 45 years have been investigated by genotyping 467 Thoroughbred horses (born between 1961 and 2006) using the Illumina Equine SNP50 bead chip, which comprises 54,602 SNPs uniformly distributed across the equine genome. The Spearman rank correlation coefficient, r, between the year of birth and F was estimated. The results indicate that inbreeding in Thoroughbreds has increased over the past 40 years, with r = 0.24, P < 0.001 demonstrating that there is a highly significant, though relatively weak correlation between the year of birth and inbreeding coefficients. Interestingly, the majority of the increase in inbreeding is post-1996 and coincides with the introduction of stallions covering larger numbers of mares.


Assuntos
Cavalos/genética , Endogamia , Animais , Feminino , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Linhagem , Estatísticas não Paramétricas , Fatores de Tempo
4.
Biol Lett ; 7(2): 316-20, 2011 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-20926431

RESUMO

The paternal origins of Thoroughbred racehorses trace back to a handful of Middle Eastern stallions, imported to the British Isles during the seventeenth century. Yet, few details of the foundation mares were recorded, in many cases not even their names (several different maternal lineages trace back to 'A Royal Mare'). This has fuelled intense speculation over their origins. We examined mitochondrial DNA from 1929 horses to determine the origin of Thoroughbred foundation mares. There is no evidence to support exclusive Arab maternal origins as some historical records have suggested, or a significant importation of Oriental mares (the term used in historic records to refer to Middle East and western Asian breeds including Arab, Akhal-Teke, Barb and Caspian). Instead, we show that Thoroughbred foundation mares had a cosmopolitan European heritage with a far greater contribution from British and Irish Native mares than previously recognized.


Assuntos
Cruzamento , Cavalos/genética , Linhagem , Animais , DNA Mitocondrial/química , Feminino , Frequência do Gene , Variação Genética , Haplótipos , Irlanda , Masculino , Oriente Médio , Reino Unido
5.
Can J Neurol Sci ; 37(5): 601-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21059505

RESUMO

OBJECTIVE: Primitive reflexes and parkinsonian signs are used by clinicians to differentiate among dementias. We reviewed our clinical sample to determine whether primitive reflexes were more prevalent in frontally-based dementias and whether parkinsonian signs were more common in dementia with Lewy bodies (DLB) than in other types of dementia. DESIGN: We retrospectively reviewed charts from 204 patients with dementia who presented for consultation at Baycrest's Ross Memory Clinic between April, 2003, to December, 2007. RESULTS: A greater proportion of subjects with DLB and dementia of the Alzheimer type with cardiovascular disease had primitive reflexes than subjects with frontotemporal dementia (FTD). Primitive reflexes were not positively predictive of FTD or vascular dementia (VaD). Dementia with Lewy bodies subjects were more likely to have parkinsonian signs than the other dementias, and bradykinesia and rigidity were positively predictive of FTD. The palmomental reflex was the most common primitive reflex in the sample, and cogwheeling was the most common parkinsonian sign. There was no significant difference between early- and late-stage groups in presence of primitive reflexes or parkinsonian signs. CONCLUSIONS: Primitive reflexes appear not to be clinically discriminative of frontally-based dementias such as FTD and VaD.


Assuntos
Transtornos Neurológicos da Marcha/epidemiologia , Transtornos Parkinsonianos/epidemiologia , Reflexo Anormal/fisiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Demência/complicações , Demência/epidemiologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Transtornos Parkinsonianos/etiologia , Prevalência , Índice de Gravidade de Doença
6.
Anim Genet ; 41 Suppl 2: 154-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21070290

RESUMO

One hundred and eighty-nine Thoroughbred horses that had won Graded Stakes races in North America were genotyped with the Illumina Equine SNP50 bead chip. Association tests using PLINK to determine whether any SNPs were associated with optimum racing distance (7 furlongs and under compared to 8-10 furlongs) identified a locus on ECA18 that was statistically significant (-log 10 EMP2=1.63) at the genome-wide level following permutation analysis (10,000 permutations). Bioinformatic analysis revealed that the two ECA18 SNPs with the highest statistical significance spanned the MSTN (myostatin) locus. Mutations in myostatin in several mammalian species have been associated with increased muscling, with a preferential increase in fast glycolytic type IIB fibres, which would increase power potential. Thoroughbred horses that race over sprint distances, which are 5-7 furlongs, are often characterized by impressive hind quarter musculature, strongly suggesting that the association observed between the ECA18 SNPs and optimum race distance is mediated through MSTN.


Assuntos
Cavalos/genética , Miostatina/genética , Condicionamento Físico Animal , Animais , Cromossomos de Mamíferos , Cavalos/fisiologia , Polimorfismo de Nucleotídeo Único , Estados Unidos
7.
Anim Genet ; 41 Suppl 2: 145-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21070288

RESUMO

The GYS1 gene mutation that is causative of Type 1 Polysaccharide Storage Myopathy (PSSM) has been identified in more than 20 breeds of horses. However, the GYS1 mutation frequency or Type 1 PSSM prevalence within any given breed is unknown. The purpose of this study was to determine the frequency of the GYS1 mutation and prevalence of genetic susceptibility to Type 1 PSSM in selected breeds from Europe and North America. The GYS1 mutation was detected in 11 breeds, including, in order of increasing allele frequency, Shires, Morgans, Appaloosas, Quarter Horses, Paints, Exmoor Ponies, Saxon-Thuringian Coldbloods, South German Coldbloods, Belgians, Rhenish German Coldbloods and Percherons. The prevalence of genetic susceptibility to Type 1 PSSM in these breeds varied from 0.5% to 62.4%. The GYS1 mutation was not found in the sampled Thoroughbreds, Akhal-Tekes, Connemaras, Clydesdales, Norwegian Fjords, Welsh Ponies, Icelandics, Schleswig Coldbloods or Hanoverians, but failure to detect the mutation does not guarantee its absence. This knowledge will help breed associations determine whether they should screen for the GYS1 mutation and will alert veterinarians to a possible differential diagnosis for muscle pain, rhabdomyolysis or gait abnormalities.


Assuntos
Doença de Depósito de Glicogênio Tipo I/veterinária , Doenças dos Cavalos/genética , Doenças Musculares/veterinária , Animais , Predisposição Genética para Doença , Doença de Depósito de Glicogênio Tipo I/epidemiologia , Doença de Depósito de Glicogênio Tipo I/genética , Glicogênio Sintase/genética , Doenças dos Cavalos/epidemiologia , Cavalos , Doenças Musculares/epidemiologia , Doenças Musculares/genética , Mutação , Prevalência , Especificidade da Espécie
8.
Tissue Antigens ; 73(3): 250-4, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19254256

RESUMO

Anal furunculosis (AF) primarily affects German shepherd dogs (GSD) and is characterised by inflammation and ulceration of the perianal tissues with development of cutaneous sinuses or rectocutaneous fistulae. Investigation of pattern recognition receptor (PRR) function has suggested that defective responses might occur in AF-affected GSD. The aim of the current study was to investigate whether canine PRR genes are involved in determining susceptibility to AF in this breed. Chromosomal location and coding sequences for NOD1, NOD2, TLR1, TLR2, TLR4, TLR5, TLR6 and TLR9 were determined and microsatellite markers identified for each gene. Microsatellite genotyping of 100 control GSD and 47 AF-affected GSD showed restricted allelic variation for AHT H91 (associated with TLR5) and REN216 NO5 (associated with both TLR1 and TLR6) compared with non-GSD dogs. Genotyping of single nucleotide polymorphisms identified in canine TLR1, TLR5, TLR6 and NOD2 genes failed to show any significant associations between PRR polymorphisms and AF. The highly restricted PRR genotypes seen in GSD are likely to have resulted from selective breeding and might influence innate immune responses in this breed.


Assuntos
Doenças do Ânus/veterinária , Doenças do Cão/genética , Furunculose/veterinária , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Receptores Toll-Like/genética , Animais , Doenças do Ânus/genética , Cães , Furunculose/genética , Receptor 1 Toll-Like/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Receptor 5 Toll-Like/genética , Receptor 6 Toll-Like/genética , Receptor Toll-Like 9/genética
9.
Tissue Antigens ; 73(3): 218-24, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19254251

RESUMO

Anal furunculosis (AF) is a chronic inflammatory disease of perianal tissues that particularly affects German Shepherd dogs (GSD). An immune-mediated aetiopathogenesis is suggested by T-cell infiltration, upregulated cytokine gene expression, clinical response to ciclosporin therapy and a strong genetic association with the DLA-DRB1*00101 allele. Given the close proximity of TNFA and DLA-DRB1 in the canine major histocompatibility complex (MHC), together with the strong linkage disequilibrium (LD) observed across this region, the primary disease association could be with either locus. We have investigated whether there may be an association of AF with TNFA gene polymorphism in GSDs. Cohorts of AF-affected and AF-unaffected GSDs of known dog leucocyte antigen (DLA) class II profile were genotyped for 10 single nucleotide polymorphisms (SNPs) in the canine TNFA locus using Sequenom iPLEX technology. Seven discrete TNFA haplotypes were identified in GSDs for combinations of these SNPs. TNFA haplotype frequencies were compared in cases and controls. The TNFA haplotype 3 (ATCGTTACGG), was at significantly increased frequency in cases (29% vs 15%, OR 2.5, 95% CI 1.4-4.8; P = 0.003). All seven discrete TNFA SNP haplotypes were examined for their association with DLA-DRB1/DQA1/DQB1 established haplotypes. TNFA haplotype 3 was preferentially associated with both DLA-DRB1*00101(3A)- and DLA-DRB1*00102(3B)-positive haplotypes. The DLA-DRB1* 00101/TNFA-3A haplotype was significantly associated with AF (19.3% vs 5.8%; OR 3.7, 95% CI: 1.5-8.9; P = 0.003), whereas the DLA-DRB1*00102/TNFA-3B haplotype was not (P = NS). These findings suggest that susceptibility to AF in GSDs is primarily associated with DLA-DRB1*00101 and any association with the TNFA locus is secondary and is likely to be because of LD.


Assuntos
Doenças do Ânus/veterinária , Doenças do Cão/genética , Furunculose/veterinária , Antígenos HLA-DR/genética , Desequilíbrio de Ligação/genética , Fator de Necrose Tumoral alfa/genética , Animais , Doenças do Ânus/genética , Doenças do Ânus/imunologia , Doenças do Cão/imunologia , Cães , Furunculose/genética , Furunculose/imunologia , Predisposição Genética para Doença , Cadeias HLA-DRB1 , Polimorfismo de Nucleotídeo Único
10.
Cytogenet Genome Res ; 122(1): 28-36, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18931483

RESUMO

A comprehensive second-generation whole genome radiation hybrid (RH II), cytogenetic and comparative map of the horse genome (2n = 64) has been developed using the 5000rad horse x hamster radiation hybrid panel and fluorescence in situ hybridization (FISH). The map contains 4,103 markers (3,816 RH; 1,144 FISH) assigned to all 31 pairs of autosomes and the X chromosome. The RH maps of individual chromosomes are anchored and oriented using 857 cytogenetic markers. The overall resolution of the map is one marker per 775 kilobase pairs (kb), which represents a more than five-fold improvement over the first-generation map. The RH II incorporates 920 markers shared jointly with the two recently reported meiotic maps. Consequently the two maps were aligned with the RH II maps of individual autosomes and the X chromosome. Additionally, a comparative map of the horse genome was generated by connecting 1,904 loci on the horse map with genome sequences available for eight diverse vertebrates to highlight regions of evolutionarily conserved syntenies, linkages, and chromosomal breakpoints. The integrated map thus obtained presents the most comprehensive information on the physical and comparative organization of the equine genome and will assist future assemblies of whole genome BAC fingerprint maps and the genome sequence. It will also serve as a tool to identify genes governing health, disease and performance traits in horses and assist us in understanding the evolution of the equine genome in relation to other species.


Assuntos
Mapeamento Cromossômico/veterinária , Cavalos/genética , Animais , Mapeamento Cromossômico/métodos , Cromossomos Artificiais Bacterianos/genética , Citogenética , Marcadores Genéticos , Hibridização in Situ Fluorescente/veterinária , Escore Lod , Mapeamento Físico do Cromossomo/veterinária , Mapeamento de Híbridos Radioativos/veterinária , Especificidade da Espécie
11.
Cytogenet Genome Res ; 111(1): 5-15, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16093715

RESUMO

A comprehensive male linkage map was generated by adding 359 new, informative microsatellites to the International Equine Gene Map half-sibling reference families and by combining genotype data from three independent mapping resources: a full sibling family created at the Animal Health Trust in Newmarket, United Kingdom, eight half-sibling families from Sweden and two half-sibling families from the University of California, Davis. Because the combined data were derived primarily from half-sibling families, only autosomal markers were analyzed. The map was constructed from a total of 766 markers distributed on the 31 equine chromosomes. It has a higher marker density than that of previously reported maps, with 626 markers linearly ordered and 140 other markers assigned to a chromosomal region. Fifty-nine markers (7%) failed to meet the criteria for statistical evidence of linkage and remain unassigned. The map spans 3,740 cM with an average distance of 6.3 cM between markers. Fifty-five percent of the intervals are < or = 5 cM and only 3% > or = 20 cM. The present map demonstrates the cohesiveness of the different data sets and provides a single resource for genome scan analyses and integration with the radiation hybrid map.


Assuntos
Mapeamento Cromossômico/métodos , Cavalos/genética , Animais , Marcadores Genéticos , Funções Verossimilhança , Cromossomo X
12.
Neurology ; 54(6): 1337-44, 2000 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-10746607

RESUMO

OBJECTIVE: To evaluate the ability of measures of initial severity, tests of attention, and demographic characteristics to predict recovery of continuous memory for words over a 24-hour period in patients with acute traumatic brain injury. METHODS: Recovery of continuous memory was assessed prospectively in 94 patients with nonpenetrating traumatic brain injury. A classification and regression tree analysis identified a hierarchical subset of variables that may be used as a simple guideline for predicting recovery of continuous memory. Weibull regression models evaluated and compared the predictive ability of multiple variables. RESULTS: Four groups of patients were identified based on measures of severity of injury and demographic characteristics. These four groups had recovery profiles that were more precise than could be obtained by using the Glasgow Coma Scale alone: mild, about 1 week to recovery of continuous memory; moderate, 1 to 4 weeks; severe, 2 to 6 weeks; and extremely severe, 4 to 8 weeks. Regression analysis confirmed that measures of capacity (inherent resources such as indicated by age) and compromise (general functional brain state measured neuropsychologically) improved prediction over models based only on injury severity measures, such as the Glasgow Coma Scale. CONCLUSIONS: Approaches to predicting recovery of continuous memory in the acute period after traumatic brain injury that take into account multiple measures provide a more sensitive predictive index.


Assuntos
Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Memória/fisiologia , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Valor Preditivo dos Testes , Análise de Regressão
13.
Cytogenet Genome Res ; 102(1-4): 201-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14970703

RESUMO

Comparative biochemical and histopathological data suggest that a deficiency in the glycogen branching enzyme (GBE) is responsible for a fatal neonatal disease in Quarter Horse foals that closely resembles human glycogen storage disease type IV (GSD IV). Identification of DNA markers closely linked to the equine GBE1 gene would assist us in determining whether a mutation in this gene leads to the GSD IV-like condition. FISH using BAC clones as probes assigned the equine GBE1 gene to a marker deficient region of ECA26q12-->q13. Four other genes, ROBO2, ROBO1, POU1F1, and HTR1F, that flank GBE1 within a 10-Mb segment of HSA3p12-->p11, were tightly linked to equine GBE1 when analyzed on the Texas A&M University 5000 rad equine radiation hybrid panel, while the GLB1, MITF, RYBP, and PROS1 genes that flank this 10-Mb interval were not linked with markers in the GBE1 group. A polymorphic microsatellite (GBEms1) in a GBE1 BAC clone was then identified and genetically mapped to ECA26 on the Animal Health Trust full-sibling equine reference family. All Quarter Horse foals affected with GSD IV were homozygous for an allele of GBEms1, as well as an allele of the most closely linked microsatellite marker, while a control horse population showed significant allelic variation with these markers. This data provides strong molecular genetic support for the candidacy of the GBE1 locus in equine GSD IV.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/genética , Mapeamento Cromossômico/métodos , Mapeamento Cromossômico/veterinária , Doença de Depósito de Glicogênio Tipo IV/genética , Doença de Depósito de Glicogênio Tipo IV/veterinária , Doenças dos Cavalos/genética , Cavalos/genética , Alelos , América , Animais , Ligação Genética/genética , Hibridização in Situ Fluorescente/métodos , Hibridização in Situ Fluorescente/veterinária , Repetições de Microssatélites/genética , Mapeamento de Híbridos Radioativos/métodos , Mapeamento de Híbridos Radioativos/veterinária , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/veterinária
14.
Neuromuscul Disord ; 9(5): 289-95, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10407848

RESUMO

We have determined the molecular basis for skeletal myopathy and dilated cardiomyopathy in two male German short-haired pointer (GSHP) littermates. Analysis of skeletal muscle demonstrated a complete absence of dystrophin on Western blot analysis. PCR analysis of genomic DNA revealed a deletion encompassing the entire dystrophin gene. Molecular cytogenetic analysis of lymphocytes from the dam and both dystrophic pups confirmed a visible deletion in the p21 region of the affected canine X chromosome. Utrophin is up-regulated in the skeletal muscle, but does not appear to ameliorate the dystrophic canine phenotype. This new canine model should further our understanding of the physiological and biochemical processes in Duchenne muscular dystrophy.


Assuntos
Doenças do Cão/genética , Distrofina/genética , Distrofia Muscular Animal/genética , Animais , Biópsia , Western Blotting , Deleção Cromossômica , Creatina Quinase/sangue , DNA/genética , Modelos Animais de Doenças , Doenças do Cão/patologia , Cães , Hibridização in Situ Fluorescente , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofia Muscular Animal/patologia , Mutação , Reação em Cadeia da Polimerase , Cromossomo X/genética
15.
Proc Biol Sci ; 266(1420): 649-56, 1999 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-10331286

RESUMO

Thirty female dromedary camels were inseminated on a total of 50 occasions with 2-4 ml of fresh guanaco semen diluted with an equal volume of commercially available camel semen extender. Similarly, nine female guanacos were inseminated on 34 occasions with 4-6 ml of fresh, diluted camel semen. Only two of the dromedary females conceived; one aborted a female foetus on day 260 of gestation and the other gave birth to a stillborn female calf on day 365. Six conceptions occurred in the female guanacos. Two of these conceptuses, diagnosed by ultrasound, were resorbed between days 25 and 40 of gestation, one female foetus was aborted on day 291, another female foetus was aborted on day 302, and one female calf was stillborn on day 365 of gestation. The sixth foetus, a male, was born prematurely but alive after a 328-day gestation. It had a phenotypic appearance intermediate between that of a camel and a guanaco and its hybrid parentage was confirmed by the DNA fingerprinting of eight llama microsatellites. To our knowledge, this is the first viable hybrid ever to be produced between Old World and New World camelids, which have been reproductively isolated from one another for at least 11 million years. The preponderance of female hybrids is in accordance with Haldane's law. Histological examination of their ovaries revealed a failure of meiosis, with only an occasional abnormal oocyte surrounded by follicle cells. Although the diploid chromosone number of camels and guanacos is the same (2n = 74), sufficient genetic change has taken place to make the pairing of homologous chromosomes no longer possible.


Assuntos
Camelídeos Americanos/genética , Camelus/genética , Hibridização Genética , Animais , Camelídeos Americanos/anatomia & histologia , Camelus/anatomia & histologia , Feminino , Masculino , Ovário/anatomia & histologia , Fenótipo , Gravidez , Processos de Determinação Sexual , Especificidade da Espécie , Cromossomo Y/genética
16.
Virus Res ; 12(4): 371-81, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2543160

RESUMO

The A antigen gene from a very virulent strain of Marek's disease virus, RB-1B, has been cloned and the nucleotide sequence determined. The predicted amino acid sequence showed 99% identity to that determined for the MDV GA A antigen (Coussens and Velicer, J. Virol. 62, 2373-2379, 1988) over all but the carboxy-terminal region where the sequence diverged extensively. The divergence results from three nucleotide frameshifts in the reported sequence of the MDV GA gene which are not present in a cloned copy of the MDV GA A antigen gene sequenced by us. The MDV A antigen shows significant homology to a number of herpes virus gC homologues, the homology being most extensive in the carboxy-halves of the proteins.


Assuntos
Antígenos Virais/genética , Genes Virais , Herpesvirus Galináceo 2/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Embrião de Galinha , Genes , Herpesviridae/genética , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Viral/genética , Homologia de Sequência do Ácido Nucleico , Proteínas do Envelope Viral/genética
17.
Virus Res ; 24(2): 161-72, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1326827

RESUMO

By sequencing a fragment of 7351 bp the fowlpox virus thymidine kinase gene has been found to map to a position within the equivalent of the vaccinia HindIII I fragment. The deduced gene arrangement in fowlpox virus is I3, X, TK, I5, I6, I7, I8, G1, indicating that the homologue of the vaccinia I4 gene has been replaced by two genes X and TK. The non-essential TK gene has therefore replaced another non-essential gene, I4 (the ribonucleotide reductase large subunit) in this region. The X/TK insertion in fowlpox virus is precisely flanked by direct repeats of 15 bp suggesting that the translocation event may have involved transposition. The % identities between the fowlpox virus and vaccinia virus proteins ranged between 58.5% and 31.3%.


Assuntos
Vírus da Varíola das Aves Domésticas/genética , Genes Virais/genética , Sequências Repetitivas de Ácido Nucleico , Ribonucleotídeo Redutases/genética , Homologia de Sequência do Ácido Nucleico , Timidina Quinase/genética , Vaccinia virus/genética , Proteínas Estruturais Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Vírus da Varíola das Aves Domésticas/enzimologia , Rearranjo Gênico , Dados de Sequência Molecular , Mapeamento de Nucleotídeos , Regiões Promotoras Genéticas
18.
Virus Res ; 1(4): 303-13, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6099661

RESUMO

cDNA clones prepared from genomic RNA of coronavirus IBV have been sequenced. The nucleotide sequence for the complete 5' region of mRNA C, which is not present in mRNAs A and B, has been determined. A sequence of 1224 bases is presented which contains a long open reading frame predicting a polypeptide of molecular weight 25 443. This is in agreement with the molecular weight of 23 000 reported for the unglycosylated form of the membrane polypeptide.


Assuntos
Coronaviridae/genética , Vírus da Bronquite Infecciosa/genética , RNA Viral/análise , Proteínas Virais/genética , Sequência de Bases , Peso Molecular , RNA Mensageiro/análise , Proteínas da Matriz Viral
19.
Virus Res ; 4(2): 133-43, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3010595

RESUMO

The spike protein of avian infectious bronchitis coronavirus comprises two glycopolypeptides S1 and S2 derived by cleavage of a proglycopolypeptide So, the nucleotide sequence of which has recently been determined for the Beaudette strain (Binns, M.M. et al., 1985, J. Gen. Virol. 66, 719-726). The order of the two glycopolypeptides within So is aminoterminus(N)-S1-S2-carboxyterminus(C). To locate the N-terminus of S2 we have performed partial amino acid sequencing on S2 from IBV-Beaudette labelled with [3H]serine and from the related strain labelled with [3H]valine, leucine and isoleucine. The residues identified and their positions relative to the N-terminus of S2 were: serine, 13; valine, 6, 12; leucine, none in the first 20 residues; isoleucine, 2, 19. These results identified the N-terminus of S2 of IBV-Beaudette as serine, 520 residues from the N-terminus of S1, excluding the signal sequence. Immediately to the N-terminal side of residue 520 So has the sequence Arg-Arg-Phe-Arg-Arg; similar basic connecting peptides are a feature of several other virus spike glycoproteins. It was deduced that for IBV-Beaudette S1 comprises 519 residues (Mr 57.0K) or 514 residues (56.2K) if the connecting peptide was to be removed by carboxypeptidase-like activity in vivo while S2 has 625 residues (69.2K). Nucleotide sequencing of the cleavage region of the So gene of IBV-M41 revealed the same connecting peptide as IBV-Beaudette and that the first 20 N-terminal residues of S2 of IBV-M41 were identical to those of the Beaudette strain. IBV-Beaudette grown in Vero cells had some uncleaved So; this was cleavable by 10 micrograms/ml of trypsin and of chymotrypsin. Partial N-terminal analysis of S1 from IBV-M41 identified leucine and valine residues at positions 2 and 9 respectively from the N-terminus. This confirms the identification, made by Binns et al. (1985), of the N-terminus of S1 and the end of the signal sequence of the IBV-Beaudette spike propolypeptide. N-terminal sequencing of [3H]leucine-labelled IBV-Beaudette membrane (M) polypeptide showed leucine residues at positions 8, 16 and 22 from the N-terminus; these results confirm the open reading frame identified by M.E.G. Boursnell et al. (1984, Virus Res. 1, 303-313) in the nucleotide sequence of M. The N-terminus of the nucleocapsid (N) polypeptide appeared to be blocked.


Assuntos
Coronaviridae/análise , Vírus da Bronquite Infecciosa/análise , Precursores de Proteínas , Proteínas do Envelope Viral , Proteínas Virais , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Embrião de Galinha , Galinhas , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Vírus da Bronquite Infecciosa/genética , Isoleucina/análise , Leucina/análise , Serina/análise , Valina/análise , Proteínas do Envelope Viral/análise , Proteínas Virais/análise
20.
EXS ; 67: 415-20, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8400709

RESUMO

Canine DNA was cloned in M13 and screened for the presence of (dC-dA)n.(dG-dT)n repeats. Oligonucleotide primers were synthesised to the microsatellite flanking sequences and used in the polymerase chain reaction to amplify those loci from genomic DNA. The polymorphism of each microsatellite was estimated in a set of unrelated dogs.


Assuntos
DNA Satélite/genética , Cães/genética , Sequências Repetitivas de Ácido Nucleico , Animais , Sequência de Bases , Impressões Digitais de DNA , Feminino , Masculino , Dados de Sequência Molecular , Linhagem , Polimorfismo Genético
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