The Experts below are selected from a list of 13386 Experts worldwide ranked by ideXlab platform
Stephen J Obrien - One of the best experts on this subject based on the ideXlab platform.
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ultracontinuous single haplotype genome assemblies for the Domestic Cat felis Catus and asian leopard Cat prionailurus bengalensis
Journal of Heredity, 2020Co-Authors: Kevin R Bredemeyer, Stephen J Obrien, Andrew J Harris, Le Zhao, Nicole M Foley, Melody E Roelkeparker, Leslie A Lyons, Wesley C Warren, William J MurphyAbstract:In addition to including one of the most popular companion animals, species from the Cat family Felidae serve as a powerful system for genetic analysis of inherited and infectious disease, as well as for the study of phenotypic evolution and speciation. Previous diploid-based genome assemblies for the Domestic Cat have served as the primary reference for genomic studies within the Cat family. However, these versions suffered from poor resolution of complex and highly repetitive regions, with substantial amounts of unplaced sequence that is polymorphic or copy number variable. We sequenced the genome of a female F1 Bengal hybrid Cat, the offspring of a Domestic Cat (Felis Catus) x Asian leopard Cat (Prionailurus bengalensis) cross, with PacBio long sequence reads and used Illumina sequence reads from the parents to phase >99.9% of the reads into the two species' haplotypes. De novo assembly of the phased reads produced highly continuous haploid genome assemblies for the Domestic Cat and Asian leopard Cat, with contig N50 statistics exceeding 83 Mb for both genomes. Whole genome alignments reveal the Felis and Prionailurus genomes are colinear, and the cytogenetic differences between the homologous F1 and E4 chromosomes represent a case of centromere repositioning in the absence of a chromosomal inversion. Both assemblies offer significant improvements over the previous Domestic Cat reference genome, with a 100% increase in contiguity and the capture of the vast majority of chromosome arms in one or two large contigs. We further demonstrated that comparably accurate F1 haplotype phasing can be achieved with members of the same species when one or both parents of the trio are not available. These novel genome resources will empower studies of feline precision medicine, adaptation and speciation.
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a high resolution snp array based linkage map anchors a new Domestic Cat draft genome assembly and provides detailed patterns of recombination
G3: Genes Genomes Genetics, 2016Co-Authors: Ladeana W Hillier, Marilyn Menottiraymond, Victor A David, Robert A Grahn, Aleksey V Zimin, Rondo P Middleton, Steven S Hannah, Sher L Hendrickson, Alexey I Makunin, Stephen J ObrienAbstract:High-resolution genetic and physical maps are invaluable tools for building accurate genome assemblies, and interpreting results of genome-wide association studies (GWAS). Previous genetic and physical maps anchored good quality draft assemblies of the Domestic Cat genome, enabling the discovery of numerous genes underlying hereditary disease and phenotypes of interest to the biomedical science and breeding communities. However, these maps lacked sufficient marker density to order thousands of shorter scaffolds in earlier assemblies, which instead relied heavily on comparative mapping with related species. A high-resolution map would aid in validating and ordering chromosome scaffolds from existing and new genome assemblies. Here, we describe a high-resolution genetic linkage map of the Domestic Cat genome based on genotyping 453 Domestic Cats from several multi-generational pedigrees on the Illumina 63K SNP array. The final maps include 58,055 SNP markers placed relative to 6637 markers with unique positions, distributed across all autosomes and the X chromosome. Our final sex-averaged maps span a total autosomal length of 4464 cM, the longest described linkage map for any mammal, confirming length estimates from a previous microsatellite-based map. The linkage map was used to order and orient the scaffolds from a substantially more contiguous Domestic Cat genome assembly (Felis Catus v8.0), which incorporated ∼20 × coverage of Illumina fragment reads. The new genome assembly shows substantial improvements in contiguity, with a nearly fourfold increase in N50 scaffold size to 18 Mb. We use this map to report probable structural errors in previous maps and assemblies, and to describe features of the recombination landscape, including a massive (∼50 Mb) recombination desert (of virtually zero recombination) on the X chromosome that parallels a similar desert on the porcine X chromosome in both size and physical loCation.
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a suite of genetic markers useful in assessing wildCat felis silvestris ssp Domestic Cat felis silvestris Catus admixture
Journal of Heredity, 2011Co-Authors: Carlos A Driscoll, Nobuyuki Yamaguchi, Stephen J Obrien, David W. MacdonaldAbstract:The wildCat (Felis silvestris ssp.) is a conservation concern largely due to introgressive hybridization with its congener F. s. Catus, the common Domestic Cat. Because of a recent divergence and entirely overlapping ranges, hybridization is common and pervasive between these taxa threatening the genetic integrity of remaining wildCat populations. Identifying pure wildCats for inclusion in conservation programs using current morphological discriminants is difficult because of gross similarity between them and the Domestic, critically hampering conservation efforts. Here, we present a vetted panel of microsatellite loci and mitochondrial polymorphisms informative for each of the 5 naturally evolved wildCat subspecies and the derived Domestic Cat. We also present reference genotypes for each assignment class. Together, these marker sets and corresponding reference genotypes allow for the development of a genetic rational for defining ‘‘units of conservation’’ within a phylogenetically based taxonomy of the entire F. silvestris species complex. We anticipate this marker panel will allow conservators to assess genetic integrity and quantify admixture in managed wildCat populations and to be a starting point for more in-depth analysis of hybridization.
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a Domestic Cat x chromosome linkage map and the sex linked orange locus mapping of orange multiple origins and epistasis over nonagouti
Genetics, 2009Co-Authors: Anne Schmidtkuntzel, Stephen J Obrien, Eduardo Eizirik, Melody E Roelke, Victor A David, Alejandro A Schaffer, Steven S Hannah, George Nelson, James S Kehler, Marilyn MenottiraymondAbstract:A comprehensive genetic linkage map of the Domestic Cat X chromosome was generated with the goal of localizing the genomic position of the classic X-linked orange ( O ) locus. Microsatellite markers with an average spacing of 3 Mb were selected from sequence traces of the Cat 1.9× whole genome sequence (WGS), including the pseudoautosomal region 1 (PAR1). Extreme variation in recombination rates (centimorgans per megabase) was observed along the X chromosome, ranging from a virtual absence of recombination events in a region estimated to be >30 Mb to recombination frequencies of 15.7 cM/Mb in a segment estimated to be orange gene, placing this locus on the q arm of the X chromosome, as opposed to a previously reported loCation on the p arm. Fine mapping placed the locus between markers at positions 106 and 116.8 Mb in the current 1.9×-coverage sequence assembly of the Cat genome. Haplotype analysis revealed potential recombination events that could reduce the size of the candidate region to 3.5 Mb and suggested multiple origins for the orange phenotype in the Domestic Cat. Furthermore, epistasis of orange over nonagouti was demonstrated at the genetic level.
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an str forensic typing system for genetic individualization of Domestic Cat felis Catus samples
Journal of Forensic Sciences, 2005Co-Authors: Marilyn Menottiraymond, Victor A David, Leslie Wachter, John M Butler, Stephen J ObrienAbstract:A forensic genotyping panel of 11 tetranucleotide STR loci from the Domestic Cat was characterized and evaluated for genetic individualization of Cat tissues. We first examined 49 candidate STR loci and their frequency assessment in Domestic Cat populations. The STR loci (3–4 base pair repeat motifs), mapped in the Cat genome relative to 579 coding loci and 255 STR loci, are well distributed across the 18 feline autosomes. All loci exhibit Mendelian inheritance in a multi-generation pedigree. Eleven loci that were unlinked and were highly heterozygous in Cat breeds were selected for a forensic panel. Heterozygosity values obtained for the independent loci, ranged from 0.60–0.82, while the average Cat breed heterozygosity obtained for the 11 locus panel was 0.71 (range of 0.57–0.83). A small sample set of outbred Domestic Cats displayed a heterozygosity of 0.86 for the 11 locus panel. The power of discrimination of the panel is moderate to high in the Cat breeds examined, with an average Pm of 3.7E-06. The panel shows good potential for genetic individualization within outbred Domestic Cats with a Pm of 5.31E-08. A multiplex protocol, designed for the co-amplifiCation of the 11 loci and a gender-identifying locus, is species specific and robust, generating a product profile with as little as 0.125 nanograms of genomic DNA.
William J Murphy - One of the best experts on this subject based on the ideXlab platform.
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ultracontinuous single haplotype genome assemblies for the Domestic Cat felis Catus and asian leopard Cat prionailurus bengalensis
Journal of Heredity, 2020Co-Authors: Kevin R Bredemeyer, Stephen J Obrien, Andrew J Harris, Le Zhao, Nicole M Foley, Melody E Roelkeparker, Leslie A Lyons, Wesley C Warren, William J MurphyAbstract:In addition to including one of the most popular companion animals, species from the Cat family Felidae serve as a powerful system for genetic analysis of inherited and infectious disease, as well as for the study of phenotypic evolution and speciation. Previous diploid-based genome assemblies for the Domestic Cat have served as the primary reference for genomic studies within the Cat family. However, these versions suffered from poor resolution of complex and highly repetitive regions, with substantial amounts of unplaced sequence that is polymorphic or copy number variable. We sequenced the genome of a female F1 Bengal hybrid Cat, the offspring of a Domestic Cat (Felis Catus) x Asian leopard Cat (Prionailurus bengalensis) cross, with PacBio long sequence reads and used Illumina sequence reads from the parents to phase >99.9% of the reads into the two species' haplotypes. De novo assembly of the phased reads produced highly continuous haploid genome assemblies for the Domestic Cat and Asian leopard Cat, with contig N50 statistics exceeding 83 Mb for both genomes. Whole genome alignments reveal the Felis and Prionailurus genomes are colinear, and the cytogenetic differences between the homologous F1 and E4 chromosomes represent a case of centromere repositioning in the absence of a chromosomal inversion. Both assemblies offer significant improvements over the previous Domestic Cat reference genome, with a 100% increase in contiguity and the capture of the vast majority of chromosome arms in one or two large contigs. We further demonstrated that comparably accurate F1 haplotype phasing can be achieved with members of the same species when one or both parents of the trio are not available. These novel genome resources will empower studies of feline precision medicine, adaptation and speciation.
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supplementary material for radiation hybrid mapping of 304 novel microsatellites in the Domestic Cat genome
2017Co-Authors: Marilyn Menottiraymond, Alejandro A Schaffer, V A David, R Agarwala, Robert M Stephens, S J Obrien, William J MurphyAbstract:Effective utilization of the Domestic Cat as an animal model for hereditary and infectious disease requires the development and implementation of high quality gene maps incorporating microsatellites and conserved coding gene markers. Previous feline linkage and radiation hybrid maps have lacked sufficient microsatellite coverage on all chromosomes to make effective use of full genome scans. Here we report the isolation and genomic mapping of 304 novel polymorphic repeat loci in the feline genome. The new loci were mapped in the Domestic Cat radiation hybrid panel using an automated fluorescent Taq -Man based assay. The addition of these 304 microsatellites brings the total number of microsatellites mapped in the feline genome to 580, and the total number of loci placed onto the RH map to 1,126. Microsatellites now span every autosome with an average spacing of roughly one polymorphic STR every five centimorgans, and full genome coverage of one marker every 2.7 megabases. These loci now provide a useful tool for undertaking full-genome scans to identify genes associated with phenotypes of interest, such as those relating to hereditary disease, coat color, patterning and morphology. These resources can also be extended to the remaining 36 species of the Cat family for population genetic and evolutionary genomic analyses.
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second generation integrated genetic linkage radiation hybrid maps of the Domestic Cat felis Catus
Journal of Heredity, 2003Co-Authors: Marilyn Menottiraymond, Stephen J Obrien, Victor A David, Zhaohong Chen, K A Menotti, Shan Sun, Alejandro A Schaffer, Richa Agarwala, James F Tomlin, William J MurphyAbstract:We report construction of second-generation integrated genetic linkage and radiation hybrid (RH) maps in the Domestic Cat (Felis Catus) that exhibit a high level of marker concordance and provide near-full genome coverage. A total of 864 markers, including 585 coding loci (type I markers) and 279 polymorphic microsatellite loci (type II markers), are now mapped in the Cat genome. We generated the genetic linkage map utilizing a multigeneration interspecies backcross pedigree between the Domestic Cat and the Asian leopard Cat (Prionailurus bengalensis). Eighty-one type I markers were integrated with 247 type II markers from a first-generation map to generate a map of 328 loci (320 autosomal and 8 X-linked) distributed in 47 linkage groups, with an average intermarker spacing of 8 cM. Genome coverage spans approximately 2,650 cM, allowing an estimate for the genetic length of the sex-averaged map as 3,300 cM. The 834-locus second-generation Domestic Cat RH map was generated from the incorporation of 579 type I and 255 type II loci. Type I markers were added using targeted selection to cover either genomic regions underrepresented in the first-generation map or to refine breakpoints in human/feline synteny. The integrated linkage and RH maps reveal approximately 110 conserved segments ordered between the human and feline genomes, and provide extensive anchored reference marker homologues that connect to the more gene dense human and mouse sequence maps, suitable for positional cloning appliCations.
Walter Basso - One of the best experts on this subject based on the ideXlab platform.
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Fatal infection with emerging apicomplexan parasite Hepatozoon silvestris in a Domestic Cat
Parasites & Vectors, 2018Co-Authors: Kristel Kegler, Ursina Nufer, Amer Alic, Horst Posthaus, Philipp Olias, Walter BassoAbstract:Background Hepatozoon silvestris is an emerging apicomplexan parasite discovered in European wild Cats from Bosnia and Herzegovina and blood samples of a Domestic Cat from Southern Italy in 2017. It has also been identified in Ixodes ricinus collected from a Domestic Cat in Wales, UK, in 2018. The clinical relevance, pathogenesis and epidemiology of this novel Hepatozoon species are not yet understood. Thus, the objective of this paper was to report and describe the first fatal case of an H. silvestris infection in a Domestic Cat. Results The Cat, which originated from Switzerland, died shortly after presenting clinical signs of lethargy, weakness and anorexia. At necropsy, no specific lesions were observed. Histopathology of the heart revealed a severe lympho-plasmacytic and histiocytic myocarditis. Mature and developing protozoal meronts morphologically compatible with Hepatozoon species were observed associated with the myocardial inflammation. No other lesions were present in any other organ evaluated, and the Cat tested negative for retroviral and other immunosuppressive infectious agents. Polymerase chain reaction from the myocardium resulted in a specific amplicon of the Hepatozoon 18S rRNA gene. Sequencing and BLAST analysis revealed 100% sequence identity with H. silvestris. Conclusions The severity of the infection with fatal outcome in an otherwise healthy animal suggests a high virulence of H. silvestris for Domestic Cats. The presence of this emerging parasite in a Domestic Cat in Switzerland with no travel history provides further evidence for a geographical distribution throughout Europe.
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fatal infection with emerging apicomplexan parasite hepatozoon silvestris in a Domestic Cat
Parasites & Vectors, 2018Co-Authors: Kristel Kegler, Ursina Nufer, Amer Alic, Horst Posthaus, Philipp Olias, Walter BassoAbstract:Hepatozoon silvestris is an emerging apicomplexan parasite discovered in European wild Cats from Bosnia and Herzegovina and blood samples of a Domestic Cat from Southern Italy in 2017. It has also been identified in Ixodes ricinus collected from a Domestic Cat in Wales, UK, in 2018. The clinical relevance, pathogenesis and epidemiology of this novel Hepatozoon species are not yet understood. Thus, the objective of this paper was to report and describe the first fatal case of an H. silvestris infection in a Domestic Cat. The Cat, which originated from Switzerland, died shortly after presenting clinical signs of lethargy, weakness and anorexia. At necropsy, no specific lesions were observed. Histopathology of the heart revealed a severe lympho-plasmacytic and histiocytic myocarditis. Mature and developing protozoal meronts morphologically compatible with Hepatozoon species were observed associated with the myocardial inflammation. No other lesions were present in any other organ evaluated, and the Cat tested negative for retroviral and other immunosuppressive infectious agents. Polymerase chain reaction from the myocardium resulted in a specific amplicon of the Hepatozoon 18S rRNA gene. Sequencing and BLAST analysis revealed 100% sequence identity with H. silvestris. The severity of the infection with fatal outcome in an otherwise healthy animal suggests a high virulence of H. silvestris for Domestic Cats. The presence of this emerging parasite in a Domestic Cat in Switzerland with no travel history provides further evidence for a geographical distribution throughout Europe.
Marilyn Menottiraymond - One of the best experts on this subject based on the ideXlab platform.
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supplementary material for radiation hybrid mapping of 304 novel microsatellites in the Domestic Cat genome
2017Co-Authors: Marilyn Menottiraymond, Alejandro A Schaffer, V A David, R Agarwala, Robert M Stephens, S J Obrien, William J MurphyAbstract:Effective utilization of the Domestic Cat as an animal model for hereditary and infectious disease requires the development and implementation of high quality gene maps incorporating microsatellites and conserved coding gene markers. Previous feline linkage and radiation hybrid maps have lacked sufficient microsatellite coverage on all chromosomes to make effective use of full genome scans. Here we report the isolation and genomic mapping of 304 novel polymorphic repeat loci in the feline genome. The new loci were mapped in the Domestic Cat radiation hybrid panel using an automated fluorescent Taq -Man based assay. The addition of these 304 microsatellites brings the total number of microsatellites mapped in the feline genome to 580, and the total number of loci placed onto the RH map to 1,126. Microsatellites now span every autosome with an average spacing of roughly one polymorphic STR every five centimorgans, and full genome coverage of one marker every 2.7 megabases. These loci now provide a useful tool for undertaking full-genome scans to identify genes associated with phenotypes of interest, such as those relating to hereditary disease, coat color, patterning and morphology. These resources can also be extended to the remaining 36 species of the Cat family for population genetic and evolutionary genomic analyses.
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a high resolution snp array based linkage map anchors a new Domestic Cat draft genome assembly and provides detailed patterns of recombination
G3: Genes Genomes Genetics, 2016Co-Authors: Ladeana W Hillier, Marilyn Menottiraymond, Victor A David, Robert A Grahn, Aleksey V Zimin, Rondo P Middleton, Steven S Hannah, Sher L Hendrickson, Alexey I Makunin, Stephen J ObrienAbstract:High-resolution genetic and physical maps are invaluable tools for building accurate genome assemblies, and interpreting results of genome-wide association studies (GWAS). Previous genetic and physical maps anchored good quality draft assemblies of the Domestic Cat genome, enabling the discovery of numerous genes underlying hereditary disease and phenotypes of interest to the biomedical science and breeding communities. However, these maps lacked sufficient marker density to order thousands of shorter scaffolds in earlier assemblies, which instead relied heavily on comparative mapping with related species. A high-resolution map would aid in validating and ordering chromosome scaffolds from existing and new genome assemblies. Here, we describe a high-resolution genetic linkage map of the Domestic Cat genome based on genotyping 453 Domestic Cats from several multi-generational pedigrees on the Illumina 63K SNP array. The final maps include 58,055 SNP markers placed relative to 6637 markers with unique positions, distributed across all autosomes and the X chromosome. Our final sex-averaged maps span a total autosomal length of 4464 cM, the longest described linkage map for any mammal, confirming length estimates from a previous microsatellite-based map. The linkage map was used to order and orient the scaffolds from a substantially more contiguous Domestic Cat genome assembly (Felis Catus v8.0), which incorporated ∼20 × coverage of Illumina fragment reads. The new genome assembly shows substantial improvements in contiguity, with a nearly fourfold increase in N50 scaffold size to 18 Mb. We use this map to report probable structural errors in previous maps and assemblies, and to describe features of the recombination landscape, including a massive (∼50 Mb) recombination desert (of virtually zero recombination) on the X chromosome that parallels a similar desert on the porcine X chromosome in both size and physical loCation.
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a Domestic Cat x chromosome linkage map and the sex linked orange locus mapping of orange multiple origins and epistasis over nonagouti
Genetics, 2009Co-Authors: Anne Schmidtkuntzel, Stephen J Obrien, Eduardo Eizirik, Melody E Roelke, Victor A David, Alejandro A Schaffer, Steven S Hannah, George Nelson, James S Kehler, Marilyn MenottiraymondAbstract:A comprehensive genetic linkage map of the Domestic Cat X chromosome was generated with the goal of localizing the genomic position of the classic X-linked orange ( O ) locus. Microsatellite markers with an average spacing of 3 Mb were selected from sequence traces of the Cat 1.9× whole genome sequence (WGS), including the pseudoautosomal region 1 (PAR1). Extreme variation in recombination rates (centimorgans per megabase) was observed along the X chromosome, ranging from a virtual absence of recombination events in a region estimated to be >30 Mb to recombination frequencies of 15.7 cM/Mb in a segment estimated to be orange gene, placing this locus on the q arm of the X chromosome, as opposed to a previously reported loCation on the p arm. Fine mapping placed the locus between markers at positions 106 and 116.8 Mb in the current 1.9×-coverage sequence assembly of the Cat genome. Haplotype analysis revealed potential recombination events that could reduce the size of the candidate region to 3.5 Mb and suggested multiple origins for the orange phenotype in the Domestic Cat. Furthermore, epistasis of orange over nonagouti was demonstrated at the genetic level.
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an str forensic typing system for genetic individualization of Domestic Cat felis Catus samples
Journal of Forensic Sciences, 2005Co-Authors: Marilyn Menottiraymond, Victor A David, Leslie Wachter, John M Butler, Stephen J ObrienAbstract:A forensic genotyping panel of 11 tetranucleotide STR loci from the Domestic Cat was characterized and evaluated for genetic individualization of Cat tissues. We first examined 49 candidate STR loci and their frequency assessment in Domestic Cat populations. The STR loci (3–4 base pair repeat motifs), mapped in the Cat genome relative to 579 coding loci and 255 STR loci, are well distributed across the 18 feline autosomes. All loci exhibit Mendelian inheritance in a multi-generation pedigree. Eleven loci that were unlinked and were highly heterozygous in Cat breeds were selected for a forensic panel. Heterozygosity values obtained for the independent loci, ranged from 0.60–0.82, while the average Cat breed heterozygosity obtained for the 11 locus panel was 0.71 (range of 0.57–0.83). A small sample set of outbred Domestic Cats displayed a heterozygosity of 0.86 for the 11 locus panel. The power of discrimination of the panel is moderate to high in the Cat breeds examined, with an average Pm of 3.7E-06. The panel shows good potential for genetic individualization within outbred Domestic Cats with a Pm of 5.31E-08. A multiplex protocol, designed for the co-amplifiCation of the 11 loci and a gender-identifying locus, is species specific and robust, generating a product profile with as little as 0.125 nanograms of genomic DNA.
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second generation integrated genetic linkage radiation hybrid maps of the Domestic Cat felis Catus
Journal of Heredity, 2003Co-Authors: Marilyn Menottiraymond, Stephen J Obrien, Victor A David, Zhaohong Chen, K A Menotti, Shan Sun, Alejandro A Schaffer, Richa Agarwala, James F Tomlin, William J MurphyAbstract:We report construction of second-generation integrated genetic linkage and radiation hybrid (RH) maps in the Domestic Cat (Felis Catus) that exhibit a high level of marker concordance and provide near-full genome coverage. A total of 864 markers, including 585 coding loci (type I markers) and 279 polymorphic microsatellite loci (type II markers), are now mapped in the Cat genome. We generated the genetic linkage map utilizing a multigeneration interspecies backcross pedigree between the Domestic Cat and the Asian leopard Cat (Prionailurus bengalensis). Eighty-one type I markers were integrated with 247 type II markers from a first-generation map to generate a map of 328 loci (320 autosomal and 8 X-linked) distributed in 47 linkage groups, with an average intermarker spacing of 8 cM. Genome coverage spans approximately 2,650 cM, allowing an estimate for the genetic length of the sex-averaged map as 3,300 cM. The 834-locus second-generation Domestic Cat RH map was generated from the incorporation of 579 type I and 255 type II loci. Type I markers were added using targeted selection to cover either genomic regions underrepresented in the first-generation map or to refine breakpoints in human/feline synteny. The integrated linkage and RH maps reveal approximately 110 conserved segments ordered between the human and feline genomes, and provide extensive anchored reference marker homologues that connect to the more gene dense human and mouse sequence maps, suitable for positional cloning appliCations.
David E. Wildt - One of the best experts on this subject based on the ideXlab platform.
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Glycolytic Enzyme Activity Is Essential for Domestic Cat (Felis Catus) and Cheetah (Acinonyx jubatus) Sperm Motility and Viability in a Sugar-Free Medium
Biology of Reproduction, 2011Co-Authors: Kimberly A. Terrell, Nicola M. Anthony, Linda M. Penfold, Barry D Bavister, Laurie Marker, Stanley P. Leibo, David E. Wildt, Adrienne E CrosierAbstract:We have previously reported a lack of glucose uptake in Domestic Cat and cheetah spermatozoa, despite observing that these cells produce lactate at rates that correlate positively with sperm function. To elucidate the role of glycolysis in felid sperm energy production, we conducted a comparative study in the Domestic Cat and cheetah, with the hypothesis that sperm motility and viability are maintained in both species in the absence of glycolytic metabolism and are fueled by endogenous substrates. Washed ejaculates were incubated in chemically defined medium in the presence/absence of glucose and pyruvate. A second set of ejaculates was exposed to a chemical inhibitor of either lactate dehydrogenase (sodium oxamate) or glyceraldehyde-3-phosphate dehydrogenase (alpha-chlorohydrin). Sperm function (motility and acrosomal integrity) and lactate production were assessed, and a subset of spermatozoa was assayed for intracellular glycogen. In both the Cat and cheetah, sperm function was maintained without exogenous substrates and following lactate dehydrogenase inhibition. Lactate production occurred in the absence of exogenous hexoses, but only if pyruvate was present. Intracellular glycogen was not detected in spermatozoa from either species. Unexpectedly, glycolytic inhibition by alpha-chlorohydrin resulted in an immediate decline in sperm motility, particularly in the Domestic Cat. Collectively, our findings reveal an essential role of the glycolytic pathway in felid spermatozoa that is unrelated to hexose metabolism or lactate formation. Instead, glycolytic enzyme activity could be required for the metabolism of endogenous lipid-derived glycerol, with fatty acid oxidation providing the primary energy source in felid spermatozoa.
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evidence for compromised metabolic function and limited glucose uptake in spermatozoa from the teratospermic Domestic Cat felis Catus and cheetah acinonyx jubatus
Biology of Reproduction, 2010Co-Authors: Kimberly A. Terrell, Nicola M. Anthony, Linda M. Penfold, Barry D Bavister, Laurie Marker, Stanley P. Leibo, David E. Wildt, Adrienne E CrosierAbstract:Cheetahs and certain other felids consistently ejaculate high proportions (≥60%) of malformed spermatozoa, a condition known as teratospermia, which is prevalent in humans. Even seemingly normal spermatozoa from Domestic Cat teratospermic ejaculates have reduced fertilizing capacity. To understand the role of sperm metabolism in this phenomenon, we conducted a comparative study in the normospermic Domestic Cat versus the teratospermic Cat and cheetah with the general hypothesis that sperm metabolic function is impaired in males producing predominantly pleiomorphic spermatozoa. Washed ejaculates were incubated in chemically defined medium containing glucose and pyruvate. Uptake of glucose and pyruvate and production of lactate were assessed using enzyme-linked fluorescence assays. Spermatozoa from Domestic Cats and cheetahs exhibited similar metabolic profiles, with minimal glucose metabolism and approximately equimolar rates of pyruvate uptake and lactate production. Compared to normospermic counterparts,...
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sperm capacitation in the Domestic Cat felis Catus and leopard Cat felis bengalensis as studied with a salt stored zona pellucida penetration assay
Molecular Reproduction and Development, 1992Co-Authors: J. C. Andrews, Jogayle Howard, Barry D Bavister, David E. WildtAbstract:The ability of Domestic Cat or leopard Cat spermatozoa to penetrate zonae pellucidae (ZP) of salt-stored, Domestic Cat oocytes was examined as an assay for sperm capacitation. Ovarian oocytes were recovered after ovariectomy and matured in vitro for 18–36 h. Following removal of cumulus cells, the oocytes were used fresh, or stored (4°C, 0.5-24 weeks) in a HEPES-buffered hypertonic salt solution. Electroejaculated, washed sperm (2-4 × 106 sperm/ml) were preincubated for 1.0 h (38°C, 5% CO2 in air) and then co-incubated (2 × 105 sperm/ml) with fresh or stored oocytes for 6.0 h. Gametes were incubated in a protein-free, modified Tyrode's solution (TLP-PVA) or in the same medium containing 4.0 mg/ml bovine serum albumin (BSA; TALP-PVA). Treatments were compared for percentage ZP penetration (defined as sperm heads reaching more than halfway through the ZP) as an index of sperm capacitation. In both the Domestic Cat and leopard Cat, there was no difference (P > 0.05) in sperm penetration of fresh ZP (Domestic Cat, 42.5 ± 5.4%; leopard Cat, 38.6 ± 2.8%) or stored ZP (Domestic Cat, 32.4 ± 4.2%; leopard Cat, 27.6 ± 2.3%). Sperm incubated in protein-free medium (TLP-PVA) were less capable (P<0.05) of ZP penetration (Domestic Cat, 14.6 ± 5.9%; leopard Cat, 7.9 ± 3.0%) than sperm incubated in medium TALP-PVA containing BSA (Domestic Cat, 60.3 ± 5.9%; leopard Cat, 58.4 ± 3.0%). These data indiCate that (1) albumin facilitates capacitation and ZP penetrating ability of Cat spermatozoa; (2) Domestic Cat ZP appear to lack a block to heterospecific penetration by “foreign” (leopard Cat) sperm; and (3) penetration of stored Domestic Cat ZP can be used as an index of sperm capacitation in the Domestic Cat and the leopard Cat.