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Tariq Ezaz - One of the best experts on this subject based on the ideXlab platform.

  • Identification of interleukin genes in Pogona Vitticeps using a de novo transcriptome assembly from RNA-seq data
    Immunogenetics, 2016
    Co-Authors: Alexandra Livernois, Kristine Hardy, Renae Domaschenz, Tariq Ezaz, Stephen D Sarre, Alexie Papanicolaou, Arthur Georges, Janine E Deakin
    Abstract:

    Interleukins are a group of cytokines with complex immunomodulatory functions that are important for regulating immunity in vertebrate species. Reptiles and mammals last shared a common ancestor more than 350 million years ago, so it is not surprising that low sequence identity has prevented divergent interleukin genes from being identified in the central bearded dragon lizard, Pogona Vitticeps , in its genome assembly. To determine the complete nucleotide sequences of key interleukin genes, we constructed full-length transcripts, using the Trinity platform, from short paired-end read RNA sequences from stimulated spleen cells. De novo transcript reconstruction and analysis allowed us to identify interleukin genes that are missing from the published P. Vitticeps assembly. Identification of key cytokines in P. Vitticeps will provide insight into the essential molecular mechanisms and evolution of interleukin gene families and allow for characterization of the immune response in a lizard for comparison with mammals.

  • Immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon, Pogona Vitticeps
    Molecular cytogenetics, 2015
    Co-Authors: Renae Domaschenz, Alexandra Livernois, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Background Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon (Pogona Vitticeps). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes.

  • Immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon, Pogona Vitticeps
    Molecular Cytogenetics, 2015
    Co-Authors: Renae Domaschenz, Alexandra Livernois, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Background Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon ( Pogona Vitticeps ). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes. Results We observed an enrichment of DNA cytosine methylation, active modifications H3K4me2 and H3K4me3, as well as the repressive mark H3K27me3 in telomeric regions on macro and microchromosomes. Microchromosomes were hypermethylated compared to macrochromosomes, as they are in chicken. However, differences between macro- and microchromosomes for histone modifications associated with actively transcribed or repressed DNA were either less distinct or not detectable. Conclusions Hypermethylation of microchromosomes compared to macrochromosomes is a shared feature between P. Vitticeps and avian species. The lack of the clear distinction between macro- and microchromosome staining patterns for active and repressive histone modifications makes it difficult to determine at this stage whether microchrosome hypermethylation is correlated with greater gene density as it is in aves, or associated with the greater GC content of P. Vitticeps microchromosomes compared to macrochromosomes.

  • immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon Pogona Vitticeps
    Molecular Cytogenetics, 2015
    Co-Authors: Alexandra Livernois, Renae Domaschenz, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon (Pogona Vitticeps). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes. We observed an enrichment of DNA cytosine methylation, active modifications H3K4me2 and H3K4me3, as well as the repressive mark H3K27me3 in telomeric regions on macro and microchromosomes. Microchromosomes were hypermethylated compared to macrochromosomes, as they are in chicken. However, differences between macro- and microchromosomes for histone modifications associated with actively transcribed or repressed DNA were either less distinct or not detectable. Hypermethylation of microchromosomes compared to macrochromosomes is a shared feature between P. Vitticeps and avian species. The lack of the clear distinction between macro- and microchromosome staining patterns for active and repressive histone modifications makes it difficult to determine at this stage whether microchrosome hypermethylation is correlated with greater gene density as it is in aves, or associated with the greater GC content of P. Vitticeps microchromosomes compared to macrochromosomes.

  • Molecular cytogenetic map of the central bearded dragon, Pogona Vitticeps (Squamata: Agamidae)
    Chromosome Research, 2013
    Co-Authors: M. J. Young, Stephen D Sarre, D. O’meally, A. Georges, Tariq Ezaz
    Abstract:

    Reptiles, as the sister group to birds and mammals, are particularly valuable for comparative genomic studies among amniotes. The Australian central bearded dragon ( Pogona Vitticeps ) is being developed as a reptilian model for such comparisons, with whole-genome sequencing near completion. The karyotype consists of 6 pairs of macrochromosomes and 10 pairs microchromosomes (2 n  = 32), including a female heterogametic ZW sex microchromosome pair. Here, we present a molecular cytogenetic map for P . Vitticeps comprising 87 anchor bacterial artificial chromosome clones that together span each macro- and microchromosome. It is the first comprehensive cytogenetic map for any non-avian reptile. We identified an active nucleolus organizer region (NOR) on the sub-telomeric region of 2q by mapping 18S rDNA and Ag-NOR staining. We identified interstitial telomeric sequences in two microchromosome pairs and the W chromosome, indicating that microchromosome fusion has been a mechanism of karyotypic evolution in Australian agamids within the last 21 to 19 million years. Orthology searches against the chicken genome revealed an intrachromosomal rearrangement of P . Vitticeps 1q, identified regions orthologous to chicken Z on P . Vitticeps 2q, snake Z on P . Vitticeps 6q and the autosomal microchromosome pair in P . Vitticeps orthologous to turtle Pelodiscus sinensis ZW and lizard Anolis carolinensis XY. This cytogenetic map will be a valuable reference tool for future gene mapping studies and will provide the framework for the work currently underway to physically anchor genome sequences to chromosomes for this model Australian squamate.

Arthur Georges - One of the best experts on this subject based on the ideXlab platform.

  • Corticosterone does not have a role in temperature sex reversal in the central bearded dragon (Pogona Vitticeps).
    Journal of experimental zoology. Part A Ecological and integrative physiology, 2021
    Co-Authors: Meghan Castelli, Arthur Georges, Clare E. Holleley
    Abstract:

    Environmental sex determination (ESD) is common among ectothermic vertebrates. The stress axis and production of stress hormones (corticosteroids) regulates ESD in fish, but evidence of a similar influence in reptiles is sparse and conflicting. The central bearded dragon (Pogona Vitticeps) has a system of sex determination involving the interplay between sex chromosomes (ZZ/ZW female heterogamety) and the thermal environment. High egg incubation temperatures induce sex reversal of the ZZ genotype, feminizing chromosomally male individuals. Here we show that corticosterone elevation is not associated with sex reversal in the central bearded dragon, either during embryonic development or adulthood. We also demonstrate experimentally that sex determination is not affected by corticosterone injection into the yolk. This strongly suggests that stress axis upregulation by high temperature during incubation does not cause sex reversal in P. Vitticeps. Our work is in general agreement with other research in reptiles, which suggests that the stress axis does not mediate sex in reptiles with ESD. Alternative biological systems may be responsible for capturing environmental conditions during reptile development, such as cellular calcium and redox regulation or the action of temperature-sensitive splicing factors.

  • MicroRNA dynamics during hibernation of the Australian central bearded dragon (Pogona Vitticeps)
    Scientific Reports, 2020
    Co-Authors: Alexander Capraro, Arthur Georges, Hardip R. Patel, Denis O‘meally, Shafagh A. Waters, Paul D. Waters
    Abstract:

    Hibernation is a physiological state employed by many animals that are exposed to limited food and adverse winter conditions. Controlling tissue-specific and organism wide changes in metabolism and cellular function requires precise regulation of gene expression, including by microRNAs (miRNAs). Here we profile miRNA expression in the central bearded dragon ( Pogona Vitticeps ) using small RNA sequencing of brain, heart, and skeletal muscle from individuals in late hibernation and four days post-arousal. A total of 1295 miRNAs were identified in the central bearded dragon genome; 664 of which were novel to central bearded dragon. We identified differentially expressed miRNAs (DEmiRs) in all tissues and correlated mRNA expression with known and predicted target mRNAs. Functional analysis of DEmiR targets revealed an enrichment of differentially expressed mRNA targets involved in metabolic processes. However, we failed to reveal biologically relevant tissue-specific processes subjected to miRNA-mediated regulation in heart and skeletal muscle. In brain, neuroprotective pathways were identified as potential targets regulated by miRNAs. Our data suggests that miRNAs are necessary for modulating the shift in cellular metabolism during hibernation and regulating neuroprotection in the brain. This study is the first of its kind in a hibernating reptile and provides key insight into this ephemeral phenotype.

  • Reproductive phenotype predicts adult bite-force performance in sex-reversed dragons (Pogona Vitticeps).
    Journal of experimental zoology. Part A Ecological and integrative physiology, 2020
    Co-Authors: Marc E. H. Jones, Arthur Georges, Jennifer C. A. Pistevos, Natalie Cooper, A. Kristopher Lappin, Mark N. Hutchinson, Clare E. Holleley
    Abstract:

    Sex-related differences in morphology and behavior are well documented, but the relative contributions of genes and environment to these traits are less well understood. Species that undergo sex reversal, such as the central bearded dragon (Pogona Vitticeps), offer an opportunity to better understand sexually dimorphic traits because sexual phenotypes can exist on different chromosomal backgrounds. Reproductively female dragons with a discordant sex chromosome complement (sex reversed), at least as juveniles, exhibit traits in common with males (e.g., longer tails and greater boldness). However, the impact of sex reversal on sexually dimorphic traits in adult dragons is unknown. Here, we investigate the effect of sex reversal on bite-force performance, which may be important in resource acquisition (e.g., mates and/or food). We measured body size, head size, and bite force of the three sexual phenotypes in a colony of captive animals. Among adults, we found that males (ZZm) bite more forcefully than either chromosomally concordant females (ZWf) or sex-reversed females (ZZf), and this difference is associated with having relatively larger head dimensions. Therefore, adult sex-reversed females, despite apparently exhibiting male traits as juveniles, do not develop the larger head and enhanced bite force of adult male bearded dragons. This pattern is further illustrated in the full sample by a lack of positive allometry of bite force in sex-reversed females that is observed in males. The results reveal a close association between reproductive phenotype and bite force performance, regardless of sex chromosome complement.

  • Identification of interleukin genes in Pogona Vitticeps using a de novo transcriptome assembly from RNA-seq data
    Immunogenetics, 2016
    Co-Authors: Alexandra Livernois, Kristine Hardy, Renae Domaschenz, Tariq Ezaz, Stephen D Sarre, Alexie Papanicolaou, Arthur Georges, Janine E Deakin
    Abstract:

    Interleukins are a group of cytokines with complex immunomodulatory functions that are important for regulating immunity in vertebrate species. Reptiles and mammals last shared a common ancestor more than 350 million years ago, so it is not surprising that low sequence identity has prevented divergent interleukin genes from being identified in the central bearded dragon lizard, Pogona Vitticeps , in its genome assembly. To determine the complete nucleotide sequences of key interleukin genes, we constructed full-length transcripts, using the Trinity platform, from short paired-end read RNA sequences from stimulated spleen cells. De novo transcript reconstruction and analysis allowed us to identify interleukin genes that are missing from the published P. Vitticeps assembly. Identification of key cytokines in P. Vitticeps will provide insight into the essential molecular mechanisms and evolution of interleukin gene families and allow for characterization of the immune response in a lizard for comparison with mammals.

  • the dragon lizard Pogona Vitticeps has zz zw micro sex chromosomes
    Chromosome Research, 2005
    Co-Authors: Tariq Ezaz, Ikuo Miura, Stephen D Sarre, Arthur Georges, Alexander E. Quinn, Jennifer Marshall A. Graves
    Abstract:

    The bearded dragon, Pogona Vitticeps (Agamidae: Reptilia) is an agamid lizard endemic to Australia. Like crocodilians and many turtles, temperature-dependent sex determination (TSD) is common in agamid lizards, although many species have genotypic sex determination (GSD). P. Vitticeps is reported to have GSD, but no detectable sex chromosomes. Here we used molecular cytogenetic and differential banding techniques to reveal sex chromosomes in this species. Comparative genomic hybridization (CGH), GTG- and C-banding identified a highly heterochromatic microchromosome specific to females, demonstrating female heterogamety (ZZ/ZW) in this species. We isolated the P. Vitticeps W chromosome by microdissection, re-amplified the DNA and used it to paint the W. No unpaired bivalents were detected in male synaptonemal complexes at meiotic pachytene, confirming male homogamety. We conclude that P. Vitticeps has differentiated previously unidentifable W and Z micro-sex chromosomes, the first to be demonstrated in an agamid lizard. Our finding implies that heterochromatinization of the heterogametic chromosome occurred during sex chromosome differentiation in this species, as is the case in some lizards and many snakes, as well as in birds and mammals. Many GSD reptiles with cryptic sex chromosomes may also prove to have micro-sex chromosomes. Reptile microchromosomes, long dismissed as non-functional minutiae and often omitted from karyotypes, therefore deserve closer scrutiny with new and more sensitive techniques.

Yara Haridy - One of the best experts on this subject based on the ideXlab platform.

  • histological analysis of post eruption tooth wear adaptations and ontogenetic changes in tooth implantation in the acrodontan squamate Pogona Vitticeps
    PeerJ, 2018
    Co-Authors: Yara Haridy
    Abstract:

    : Teeth have been a focus of research in both extinct and extant taxa alike; a significant portion of dental literature is concerned with dental patterning and replacement. Most non-mammalian vertebrates continuously replace their dentition but an anomalous group of squamates has forgone this process in only having one tooth generation; these squamates all have apically implanted teeth, a condition known as acrodonty. Acrodont dentition and various characteristics attributed to it, including a lack of replacement, have often been defined ambiguously. This study explores this type of implantation through histology in the ontogeny of the acrodont agamid Pogona Vitticeps. The non-replacing teeth of this squamate provides an opportunity to study wear adaptations, maintenance of occlusion in a non-mammalian system, and most importantly post-eruption changes in the tooth bone interface. In this study the post-eruption changes combined with dental wear likely gives the appearance of acrodont implantation.

Stephen D Sarre - One of the best experts on this subject based on the ideXlab platform.

  • Identification of interleukin genes in Pogona Vitticeps using a de novo transcriptome assembly from RNA-seq data
    Immunogenetics, 2016
    Co-Authors: Alexandra Livernois, Kristine Hardy, Renae Domaschenz, Tariq Ezaz, Stephen D Sarre, Alexie Papanicolaou, Arthur Georges, Janine E Deakin
    Abstract:

    Interleukins are a group of cytokines with complex immunomodulatory functions that are important for regulating immunity in vertebrate species. Reptiles and mammals last shared a common ancestor more than 350 million years ago, so it is not surprising that low sequence identity has prevented divergent interleukin genes from being identified in the central bearded dragon lizard, Pogona Vitticeps , in its genome assembly. To determine the complete nucleotide sequences of key interleukin genes, we constructed full-length transcripts, using the Trinity platform, from short paired-end read RNA sequences from stimulated spleen cells. De novo transcript reconstruction and analysis allowed us to identify interleukin genes that are missing from the published P. Vitticeps assembly. Identification of key cytokines in P. Vitticeps will provide insight into the essential molecular mechanisms and evolution of interleukin gene families and allow for characterization of the immune response in a lizard for comparison with mammals.

  • Molecular cytogenetic map of the central bearded dragon, Pogona Vitticeps (Squamata: Agamidae)
    Chromosome Research, 2013
    Co-Authors: M. J. Young, Stephen D Sarre, D. O’meally, A. Georges, Tariq Ezaz
    Abstract:

    Reptiles, as the sister group to birds and mammals, are particularly valuable for comparative genomic studies among amniotes. The Australian central bearded dragon ( Pogona Vitticeps ) is being developed as a reptilian model for such comparisons, with whole-genome sequencing near completion. The karyotype consists of 6 pairs of macrochromosomes and 10 pairs microchromosomes (2 n  = 32), including a female heterogametic ZW sex microchromosome pair. Here, we present a molecular cytogenetic map for P . Vitticeps comprising 87 anchor bacterial artificial chromosome clones that together span each macro- and microchromosome. It is the first comprehensive cytogenetic map for any non-avian reptile. We identified an active nucleolus organizer region (NOR) on the sub-telomeric region of 2q by mapping 18S rDNA and Ag-NOR staining. We identified interstitial telomeric sequences in two microchromosome pairs and the W chromosome, indicating that microchromosome fusion has been a mechanism of karyotypic evolution in Australian agamids within the last 21 to 19 million years. Orthology searches against the chicken genome revealed an intrachromosomal rearrangement of P . Vitticeps 1q, identified regions orthologous to chicken Z on P . Vitticeps 2q, snake Z on P . Vitticeps 6q and the autosomal microchromosome pair in P . Vitticeps orthologous to turtle Pelodiscus sinensis ZW and lizard Anolis carolinensis XY. This cytogenetic map will be a valuable reference tool for future gene mapping studies and will provide the framework for the work currently underway to physically anchor genome sequences to chromosomes for this model Australian squamate.

  • the dragon lizard Pogona Vitticeps has zz zw micro sex chromosomes
    Chromosome Research, 2005
    Co-Authors: Tariq Ezaz, Ikuo Miura, Stephen D Sarre, Arthur Georges, Alexander E. Quinn, Jennifer Marshall A. Graves
    Abstract:

    The bearded dragon, Pogona Vitticeps (Agamidae: Reptilia) is an agamid lizard endemic to Australia. Like crocodilians and many turtles, temperature-dependent sex determination (TSD) is common in agamid lizards, although many species have genotypic sex determination (GSD). P. Vitticeps is reported to have GSD, but no detectable sex chromosomes. Here we used molecular cytogenetic and differential banding techniques to reveal sex chromosomes in this species. Comparative genomic hybridization (CGH), GTG- and C-banding identified a highly heterochromatic microchromosome specific to females, demonstrating female heterogamety (ZZ/ZW) in this species. We isolated the P. Vitticeps W chromosome by microdissection, re-amplified the DNA and used it to paint the W. No unpaired bivalents were detected in male synaptonemal complexes at meiotic pachytene, confirming male homogamety. We conclude that P. Vitticeps has differentiated previously unidentifable W and Z micro-sex chromosomes, the first to be demonstrated in an agamid lizard. Our finding implies that heterochromatinization of the heterogametic chromosome occurred during sex chromosome differentiation in this species, as is the case in some lizards and many snakes, as well as in birds and mammals. Many GSD reptiles with cryptic sex chromosomes may also prove to have micro-sex chromosomes. Reptile microchromosomes, long dismissed as non-functional minutiae and often omitted from karyotypes, therefore deserve closer scrutiny with new and more sensitive techniques.

Janine E Deakin - One of the best experts on this subject based on the ideXlab platform.

  • Identification of interleukin genes in Pogona Vitticeps using a de novo transcriptome assembly from RNA-seq data
    Immunogenetics, 2016
    Co-Authors: Alexandra Livernois, Kristine Hardy, Renae Domaschenz, Tariq Ezaz, Stephen D Sarre, Alexie Papanicolaou, Arthur Georges, Janine E Deakin
    Abstract:

    Interleukins are a group of cytokines with complex immunomodulatory functions that are important for regulating immunity in vertebrate species. Reptiles and mammals last shared a common ancestor more than 350 million years ago, so it is not surprising that low sequence identity has prevented divergent interleukin genes from being identified in the central bearded dragon lizard, Pogona Vitticeps , in its genome assembly. To determine the complete nucleotide sequences of key interleukin genes, we constructed full-length transcripts, using the Trinity platform, from short paired-end read RNA sequences from stimulated spleen cells. De novo transcript reconstruction and analysis allowed us to identify interleukin genes that are missing from the published P. Vitticeps assembly. Identification of key cytokines in P. Vitticeps will provide insight into the essential molecular mechanisms and evolution of interleukin gene families and allow for characterization of the immune response in a lizard for comparison with mammals.

  • Immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon, Pogona Vitticeps
    Molecular cytogenetics, 2015
    Co-Authors: Renae Domaschenz, Alexandra Livernois, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Background Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon (Pogona Vitticeps). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes.

  • Immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon, Pogona Vitticeps
    Molecular Cytogenetics, 2015
    Co-Authors: Renae Domaschenz, Alexandra Livernois, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Background Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon ( Pogona Vitticeps ). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes. Results We observed an enrichment of DNA cytosine methylation, active modifications H3K4me2 and H3K4me3, as well as the repressive mark H3K27me3 in telomeric regions on macro and microchromosomes. Microchromosomes were hypermethylated compared to macrochromosomes, as they are in chicken. However, differences between macro- and microchromosomes for histone modifications associated with actively transcribed or repressed DNA were either less distinct or not detectable. Conclusions Hypermethylation of microchromosomes compared to macrochromosomes is a shared feature between P. Vitticeps and avian species. The lack of the clear distinction between macro- and microchromosome staining patterns for active and repressive histone modifications makes it difficult to determine at this stage whether microchrosome hypermethylation is correlated with greater gene density as it is in aves, or associated with the greater GC content of P. Vitticeps microchromosomes compared to macrochromosomes.

  • immunofluorescent staining reveals hypermethylation of microchromosomes in the central bearded dragon Pogona Vitticeps
    Molecular Cytogenetics, 2015
    Co-Authors: Alexandra Livernois, Renae Domaschenz, Tariq Ezaz, Sudha Rao, Janine E Deakin
    Abstract:

    Studies of model organisms have demonstrated that DNA cytosine methylation and histone modifications are key regulators of gene expression in biological processes. Comparatively little is known about the presence and distribution of epigenetic marks in non-model amniotes such as non-avian reptiles whose genomes are typically packaged into chromosomes of distinct size classes. Studies of chicken karyotypes have associated the gene-richness and high GC content of microchromosomes with a distinct epigenetic landscape. To determine whether this is likely to be a common feature of amniote microchromosomes, we have analysed the distribution of epigenetic marks using immunofluorescence on metaphase chromosomes of the central bearded dragon (Pogona Vitticeps). This study is the first to study the distribution of epigenetic marks on non-avian reptile chromosomes. We observed an enrichment of DNA cytosine methylation, active modifications H3K4me2 and H3K4me3, as well as the repressive mark H3K27me3 in telomeric regions on macro and microchromosomes. Microchromosomes were hypermethylated compared to macrochromosomes, as they are in chicken. However, differences between macro- and microchromosomes for histone modifications associated with actively transcribed or repressed DNA were either less distinct or not detectable. Hypermethylation of microchromosomes compared to macrochromosomes is a shared feature between P. Vitticeps and avian species. The lack of the clear distinction between macro- and microchromosome staining patterns for active and repressive histone modifications makes it difficult to determine at this stage whether microchrosome hypermethylation is correlated with greater gene density as it is in aves, or associated with the greater GC content of P. Vitticeps microchromosomes compared to macrochromosomes.