Nuclear Deoxyribonucleic Acid Research Articles

Primer in Genetics and Genomics, Article 3-Explaining Human Diversity: The Role of DNA.

Genetic variation lays the foundation for diversity and enables humans to adapt to changing environments. The order of the nucleotides adenine, guanine, cytosine, and thymine on the deoxyribonucleic acid (DNA) molecules of the nuclear chromosomes and mitochondrial DNA (mtDNA) plays an important role in normal cell division, tissue development, and reproduction but is susceptible to alteration from a large number of random, inherited, or environmental events. Variations can range from a change in a single nucleotide to duplication of entire chromosomes. Single nucleotide polymorphisms are the major source of human heterogeneity. Other variations that can alter phenotypes and adversely impact growth, development, and health include copy number variations, aneuploidies, and structural alterations such as deletions, translocations, inversions, duplications, insertions, or mutations in mtDNA. In addition, DNA rearrangements in somatic cells underlie the uncontrolled cell growth found in cancer. This article explores the mechanisms by which variations in DNA arise and the impact those changes can have on human health.

High Throughput, Real-time, Dual-readout Testing of Intracellular Antimicrobial Activity and Eukaryotic Cell Cytotoxicity.

Traditional measures of intracellular antimicrobial activity and eukaryotic cell cytotoxicity rely on endpoint assays. Such endpoint assays require several additional experimental steps prior to readout, such as cell lysis, colony forming unit determination, or reagent addition. When performing thousands of assays, for example, during high-throughput screening, the downstream effort required for these types of assays is considerable. Therefore, to facilitate high-throughput antimicrobial discovery, we developed a real-time assay to simultaneously identify inhibitors of intracellular bacterial growth and assess eukaryotic cell cytotoxicity. Specifically, real-time intracellular bacterial growth detection was enabled by marking bacterial screening strains with either a bacterial lux operon (1st generation assay) or fluorescent protein reporters (2nd generation, orthogonal assay). A non-toxic, cell membrane-impermeant, nucleic acid-binding dye was also added during initial infection of macrophages. These dyes are excluded from viable cells. However, non-viable host cells lose membrane integrity permitting entry and fluorescent labeling of nuclear DNA (deoxyribonucleic acid). Notably, DNA binding is associated with a large increase in fluorescent quantum yield that provides a solution-based readout of host cell death. We have used this combined assay to perform a high-throughput screen in microplate format, and to assess intracellular growth and cytotoxicity by microscopy. Notably, antimicrobials may demonstrate synergy in which the combined effect of two or more antimicrobials when applied together is greater than when applied separately. Testing for in vitro synergy against intracellular pathogens is normally a prodigious task as combinatorial permutations of antibiotics at different concentrations must be assessed. However, we found that our real-time assay combined with automated, digital dispensing technology permitted facile synergy testing. Using these approaches, we were able to systematically survey action of a large number of antimicrobials alone and in combination against the intracellular pathogen, Legionella pneumophila.

High Throughput, Real-time, Dual-readout Testing of Intracellular Antimicrobial Activity and Eukaryotic Cell Cytotoxicity

Traditional measures of intracellular antimicrobial activity and eukaryotic cell cytotoxicity rely on endpoint assays. Such endpoint assays require several additional experimental steps prior to readout, such as cell lysis, colony forming unit determination, or reagent addition. When performing thousands of assays, for example, during high-throughput screening, the downstream effort required for these types of assays is considerable. Therefore, to facilitate high-throughput antimicrobial discovery, we developed a real-time assay to simultaneously identify inhibitors of intracellular bacterial growth and assess eukaryotic cell cytotoxicity. Specifically, real-time intracellular bacterial growth detection was enabled by marking bacterial screening strains with either a bacterial lux operon (1st generation assay) or fluorescent protein reporters (2nd generation, orthogonal assay). A non-toxic, cell membrane-impermeant, nucleic acid-binding dye was also added during initial infection of macrophages. These dyes are excluded from viable cells. However, non-viable host cells lose membrane integrity permitting entry and fluorescent labeling of nuclear DNA (deoxyribonucleic acid). Notably, DNA binding is associated with a large increase in fluorescent quantum yield that provides a solution-based readout of host cell death. We have used this combined assay to perform a high-throughput screen in microplate format, and to assess intracellular growth and cytotoxicity by microscopy. Notably, antimicrobials may demonstrate synergy in which the combined effect of two or more antimicrobials when applied together is greater than when applied separately. Testing for in vitro synergy against intracellular pathogens is normally a prodigious task as combinatorial permutations of antibiotics at different concentrations must be assessed. However, we found that our real-time assay combined with automated, digital dispensing technology permitted facile synergy testing. Using these approaches, we were able to systematically survey action of a large number of antimicrobials alone and in combination against the intracellular pathogen, Legionella pneumophila.

An investigation into the concurrent collection of human scent and epithelial skin cells using a non-contact sampling device

In criminal investigations, the collection of human scent often employs a non-contact, dynamic airflow device, known as the Scent Transfer Unit 100 (STU-100), to transfer volatile organic compounds (VOCs) from an object/person onto a collection material that is subsequently presented to human scent discriminating canines. Human scent is theorized to be linked to epithelial skin cells that are shed at a relatively constant rate allowing both scent and cellular material to be deposited into the environment and/or onto objects. Simultaneous collection of cellular material, with adequate levels of nuclear deoxyribonucleic acid (nDNA), and human scent using a non-invasive methodology would facilitate criminal investigations. This study evaluated the STU-100 for the concurrent collection of human scent and epithelial skin cells from a porous (paper) and non-porous (stainless steel bar) object that was held for a specified period of time in the dominant hand of twenty subjects (10 females and 10 males). Human scent analysis was performed using headspace static solid-phase microextraction with gas chromatography⿿mass spectrometry (HS-SPME/GC⿿MS). A polycarbonate filter was used to trap epithelial skin cells which, upon extraction, were subsequently analyzed, inter-laboratory, using the quantitative polymerase chain reaction (qPCR). The STU-100 proved to be inadequate for collecting the minimum number of epithelial skin cells required to obtain nuclear DNA concentrations above the limit of detection for the qPCR kit. With regard to its use for human scent collection, a reduction in the number and mass of compounds was observed when compared to samples that were directly collected. However, when the indirect collection of human scent from the two different objects was compared, a greater number and mass of compounds was observed from the non-porous object than from the porous object. This outcome suggests that the matrix composition of the scent source could affect the efficacy of the human scent collected when using a non-contact, dynamic airflow sampling device. The findings from this study are of importance because although the STU-100 proved to not be suitable for collecting epithelial skin cells for DNA analysis, its non-contact capability allows for the possibility of other potential forensic evidence, like that of human scent, to be obtained.

Involvement of Regucalcin in Protein Synthesis and Proteolysis: Regulation of the Enzyme Activity in the Cytoplasm and Nucleus

<p>Regucalcin was discovered in 1978 as a novel calcium-binding protein. The name, regucalcin, was proposed for this calcium-binding protein, which regulates various Ca<sup>2+-</sup> or Ca<sup>2+</sup>/calmodulin-dependent enzyme activations. The regucalcin gene (gene symbol;rgn) is localized on the X chromosome. Regucalcin has been demonstrated to play a multifunctional role in the regulation of intracellular calcium homeostasis, signal transduction, gene expression, cell proliferation and apoptosis in various types of cells and tissues. The cytoplasmic regucalcin translocases to the nucleus and suppresses nuclear deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) synthesis. Moreover, regucalcin has been shown to reveal a suppressive effect on protein synthesis and a stimulatory effect on protein degradation. Regucalcin has been found to inhibit aminoacyl-tRNA synthetase and activate thiol protease. Â Regucalcin may play a suppressive role in the regulation of protein turnover in cells.</p>

Endangered Rough Pigtoe Pearlymussel: Assessment of Phylogenetic Status and Genetic Differentiation of Two Disjunct Populations

Abstract We conducted a genetic characterization of two extant populations of an endangered freshwater mussel, the rough pigtoe Pleurobema plenum, in the Clinch River, Tennessee of the Tennessee River basin, and the Green River, Kentucky, of the Ohio River basin for purposes of conservation recovery planning. First, phylogenetic status of this species within the Pleurobema cordatum species complex (P. cordatum, plenum, rubrum, sintoxia) was assessed using mitochondrial ND1 deoxyribonucleic acid (DNA) sequences, which showed that all investigated species of Pleurobema are genetically distinct. Our results indicated that P. cordatum, P. plenum, P. rubrum, and P. sintoxia each represent monophyletic clades; however, the latter two species were closely related, separated by only one to three nucleotide differences. Further, DNA sequence haplotypes from both populations of P. plenum grouped together into one monophyletic clade and did not support characterizing the populations as separate species. Thus, our phylogenetic analysis confirms that populations of P. plenum in the Clinch and Green rivers are the same species. Second, we assessed genetic differentiation between P. plenum populations in each river by analyzing variation at eight nuclear DNA microsatellite loci, where FST (=0.023) and Jost’s D (=0.175) indicated genetically differentiated populations. Because these populations are geographically and demographically independent, and differentiated at nuclear microsatellite loci, recognition as management units is recommended. Additional studies are needed to determine whether there are differences at adaptive or life-history traits, such as fish host usage, shell morphology, and soft anatomy between populations, and to further investigate the phylogenetic relationship of P. rubrum and P. sintoxia.

The Regucalcin Gene may be a Key in Depression of Human Carcinogenesis

Regucalcin was discovered in 1978 as a calcium-binding protein. After that, regucalcin was demonstrated to play a multifunctional role as a suppressor protein in signal transduction in various types of cell and tissues. The regucalcin gene (gene symbol; rgn) is localized on the X chromosome. Regucalcin was found to suppress nuclear deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) synthesis in liver cells. Overexpression of endogenous regucalcin possessed suppressive effects on proliferation in the modeled rat hepatoma cells by inhibiting G1 and G2/M cell cycle arrests. Suppressed regucalcin gene expression was found to be associated with progression of hepatocarcinogenesis by proteosome analysis. Moreover, regucalcin mRNA expression was found to suppress in various human normal and tumor tissues including hepatocellular carcinoma, kidney transitional cell carcinoma, brain malignant meningioma, and lung non-small cell carcinoma of human subjects. Suppressed regucalcin gene expression may be a key in development of carcinogenesis. Development of the regucalcin gene deliver system will be expected as a novel gene therapy in clinical aspects for cancer treatment

Targeting apoptosis in autoimmune hepatitis.

Apoptosis is the predominant mechanism of liver cell death in autoimmune hepatitis, and interventions that can modulate this activity are emerging. The aim of this review was to describe the apoptotic mechanisms, possible aberrations, and opportunities for intervention in autoimmune hepatitis. Studies cited in PubMed from 1972 to 2014 for autoimmune hepatitis, apoptosis in liver disease, apoptosis mechanisms, and apoptosis treatment were examined. Apoptosis is overactive in autoimmune hepatitis, and the principal pathway of cell death is receptor mediated. Surface death receptors are activated by extrinsic factors including liver-infiltrating cytotoxic T cells and the cytokine milieu. The executioner caspases 3 and 7 cleave nuclear deoxyribonucleic acid, and the release of apoptotic bodies can stimulate inflammatory, immune, and fibrotic responses. Changes in mitochondrial membrane permeability can be initiated by caspase 8, and an intrinsic pathway of apoptosis can complement the extrinsic pathway. Defects in the apoptosis of activated effector cells can prolong their survival and sustain the immune response. Caspase inhibitors have been used in diverse experimental and human diseases to retard apoptosis. Oligonucleotides that inhibit the signaling of toll-like receptors can limit the presentation of auto-antigens, and inhibitors of apoptosis that extend the survival of effector cells can be blocked by antisense oligonucleotides. Mechanisms that enhance the clearance of apoptotic bodies and affect key signaling pathways are also feasible. Interventions that influence the survival of liver and effector cells by altering their apoptosis are candidates for study in autoimmune hepatitis.

Effects of Biovar I and Biovar II of Ureaplasma urealyticum on Sperm Parameters, Lipid Peroxidation, and Deoxyribonucleic Acid Damage in Male Infertility

To reveal the impact of 2 biovars of Ureaplasma urealyticum on the sperm of infertile men by producing reactive oxygen species (ROS). A total of 223 infertile and 146 fertile men were recruited into the study. Standard semen analysis was performed. Culturing and real-time polymerase chain reaction were used to identify biovars of U urealyticum in the semen. Semen ROS, malondialdehyde, and total superoxide dismutase levels were measured. Sperm nuclear deoxyribonucleic acid (DNA) damage was assessed of by sperm chromatin structure assay and single-cell gel electrophoresis. Biovar II infection was more frequent in infertile men (P=.036). When compared with uninfected individuals, biovar II-infected men displayed decreases in spermatozoa concentration (P=.041); biovar II and mix-infected men displayed decreases in total motility (P=.015; P=.014, respectively) and increase in leukocyte counts (P=.004; P=.003, respectively). Except for total superoxide dismutase level, indicators for peroxide including ROS level, malondialdehyde level, DNA fragmentation index and high DNA stainable in sperm chromatin structure assay, and tail moment in single-cell gel electrophoresis exhibited the significant differences between both infected groups vs the uninfected group (P<05). Compared with biovar I, biovar II is more likely to cause male infertility. Increased leukocyte counts, ROS level elevation, and subsequent spermatozoa membrane and DNA damage may be involved in this pathogenesis.

Serial Plasma Deoxyribonucleic Acid Levels as Predictors of Outcome in Acute Traumatic Brain Injury

Increased plasma deoxyribonucleic acid (DNA) levels may be associated with disease severity after acute traumatic brain injury (TBI). This study posits that increased plasma DNA levels in acute TBI are predictive of outcome. Both serial plasma nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) levels were examined in 88 consecutive patients with acute TBI and 66 control subjects. Additional samples were obtained on day 4 and day 7. Results showed that plasma nDNA and mtDNA on admission were significantly increased in patients with TBI compared with controls. Plasma nDNA, but not plasma mtDNA, levels in patients with acute TBI significantly correlated with Glasgow Coma Scale (GCS) score and Injury Severity Score (ISS) on presentation. Plasma nDNA increased significantly from day 1 to day 7 in patients with poor outcome. Its levels on presentation were independently associated with outcome and higher levels (cutoff value >72.95 ng/mL) were associated with poorer outcomes. These findings suggest plasma nDNA levels reflect the severity of cerebral damage and can be considered a neuropathologic marker of patients with acute TBI. Further studies with bigger patient populations are warranted for better unbiased comparison.

Regucalcin as a potential biomarker for metabolic and neuronal diseases

Regucalcin was initially discovered in 1978 as a regulatory protein in calcium signaling. The regucalcin gene, which is localized on the X chromosome, is found in vertebrate and invertebrate species. Regucalcin has been shown to play a pivotal role in cell regulation: maintaining of intracellular calcium homeostasis, suppressions of signal transduction, inhibition of translational protein synthesis, nuclear deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) synthesis, regulation of gene expression, and anti-effects on proliferation and apoptosis in many cell types. The expression of the regucalcin gene and its protein has been shown to alter with various metabolic diseases, and regucalcin plays an important role in the development of many pathophysiologic states. Serum regucalcin has been found to increase with liver injury, and also urinary regucalcin is elevated with kidney damage, suggesting a useful tool as biomarker for diagnosis. Moreover, regucalcin has been shown to be good tool in early diagnosis for Alzheimer's disease and other brain diseases. This review will discuss a significance of regucalcin as a clinical biomarker in various diseases.

The suppression of regucalcin gene expression may lead to hepatocarcinogenesis

Regucalcin, which was discovered in 1978 as a calcium-regulatory protein, plays a multifunctional role as a suppressor in signal transduction in various types of cells and tissues. The regucalcin gene (rgn) is localized on the X chromosome. Regucalcin was found to suppress nuclear deoxyribonucleic acid and ribonucleic acid synthesis in liver cells. Overexpression of endogenous regucalcin revealed suppressive effects on proliferation in the modeled rat hepatoma cells due to regulating the gene expression of various proteins that are involved in cell cycle and carcinogenesis. Regucalcin mRNA expression was uniquely downregulated in the development of carcinogenesis in the liver of rats in vivo. The expressions of regucalcin mRNA was found to depress in human hepatoma tissues. The suppressed regucalcin gene expression was found to be associated with progression of hepatocarcinogenesis by proteosome analysis. The regucalcin gene may be a target in the therapy of hepatocarcinoma.

Human Iris Polymorphisms: Computer–based and Genetic Assessments of Human Irises and Possible Applications in Human Identification

During personal identification we can analyse the phenotypic or genotypic complexions of a human. The ancient histories of scientific activities in this field were related to the descriptive or measurable features, called phenotype analyses. In the last decades of the 20th century, during the era of human genetics, numerous polymorphic genetic markers were discovered investigating the human nuclear or mitochondrial DNA (deoxyribonucleic acid). The results of the Human Genome Project revolutionized the applications and opened an era of the investigations for externally visible characteristics (EVCs), the so called DNA based phenotyping (age, hair–, and eye– colour investigations) using informative molecular markers. The polymorphic characteristics of the human eye are well known. This partly originates from the vessel network and the layer order of the retina or the unique construction of the initial section of the optic nerve at the eye-ground. The iris’ individuality resides in its complex textural construction. The iris’ colour and partly its patterns (variations of the Fuchs’ crypts, nevi dots, Wolfflin nodules and contraction furrows) are genetically determined. All of these previously mentioned iris polymorphisms led to the development of a number of automatic phenotypic or genotypic biometric personal identification practical applications. The aim of this study is to briefly summarize the background of this topic condensing those results which are available in this field, and to present our efforts related to a novel approach in the field of iris colour prediction.

Base Excision Repair Facilitates a Functional Relationship Between Guanine Oxidation and Histone Demethylation

Appropriately controlled epigenetic regulation is critical for the normal development and health of an organism. Misregulation of epigenetic control via deoxyribonucleic acid (DNA) methylation or histone methylation has been associated with cancer and chromosomal instability syndromes. The main function of the proteins in the base excision repair (BER) pathway is to repair DNA single-strand breaks and deamination, oxidation, and alkylation-induced DNA base damage that may result from chemotherapy, environmental exposure, or byproducts of cellular metabolism. Recent studies have suggested that one or more BER proteins may also participate in epigenetic regulation to facilitate gene expression modulation via alteration of the state of DNA methylation or via a reaction coupled to histone modification. BER proteins have also been reported to play an essential role in pluripotent stem cell reprogramming. One emerging function for BER in epigenetic regulation is the repair of base lesions induced by hydrogen peroxide as a byproduct of lysine-specific demethylase 1 (LSD1) enzymatic activity (LSD1/LSD2-coupled BER) for transcriptional regulation. To shed light on this novel role of BER, this review focuses on the repair of oxidative lesions in nuclear DNA that are induced during LSD1-mediated histone demethylation. Further, we highlight current studies suggesting a role for BER proteins in transcriptional regulation of gene expression via BER-coupled active DNA demethylation in mammalian cells. Such efforts to address the role of BER proteins in epigenetic regulation could broaden cancer therapeutic strategies to include epigenetic modifiers combined with BER inhibitors.

Effects of SGLT2 Inhibition in Human Kidney Proximal Tubular Cells—Renoprotection in Diabetic Nephropathy?

Sodium/glucose cotransporter 2 (SGLT2) inhibitors are oral hypoglycemic agents used to treat patients with diabetes mellitus. SGLT2 inhibitors block reabsorption of filtered glucose by inhibiting SGLT2, the primary glucose transporter in the proximal tubular cell (PTC), leading to glycosuria and lowering of serum glucose. We examined the renoprotective effects of the SGLT2 inhibitor empagliflozin to determine whether blocking glucose entry into the kidney PTCs reduced the inflammatory and fibrotic responses of the cell to high glucose. We used an in vitro model of human PTCs. HK2 cells (human kidney PTC line) were exposed to control 5 mM, high glucose (HG) 30 mM or the profibrotic cytokine transforming growth factor beta (TGFβ1; 0.5 ng/ml) in the presence and absence of empagliflozin for up to 72 h. SGLT1 and 2 expression and various inflammatory/fibrotic markers were assessed. A chromatin immunoprecipitation assay was used to determine the binding of phosphorylated smad3 to the promoter region of the SGLT2 gene. Our data showed that TGFβ1 but not HG increased SGLT2 expression and this occurred via phosphorylated smad3. HG induced expression of Toll-like receptor-4, increased nuclear deoxyribonucleic acid binding for nuclear factor kappa B (NF-κB) and activator protein 1, induced collagen IV expression as well as interleukin-6 secretion all of which were attenuated with empagliflozin. Empagliflozin did not reduce high mobility group box protein 1 induced NF-κB suggesting that its effect is specifically related to a reduction in glycotoxicity. SGLT1 and GLUT2 expression was not significantly altered with HG or empagliflozin. In conclusion, empagliflozin reduces HG induced inflammatory and fibrotic markers by blocking glucose transport and did not induce a compensatory increase in SGLT1/GLUT2 expression. Although HG itself does not regulate SGLT2 expression in our model, TGFβ increases SGLT2 expression through phosphorylated smad3.

Calcium Regulatory Protein, Regucalcin, may be a Key Molecule in Brain Disease

Regucalcin was discovered in 1978 as a novel calcium-binding protein [1-4]. Regucalcin (RGN) and its gene (rgn) are identified in over 15 species of vertebrate and invertebrates consisting of regucalcin family [5]. Regucalcin plays a multifunctional role in cell regulation; maintaining of intracellular calcium (Ca2+) homeostasis, suppressions of cell signaling, protein synthesis, nuclear deoxyribonucleic acid and ribonucleic acid synthesis and cell proliferation and apoptosis, and regulation of gene expression in various tissue and cell types [6,7]. Regucalcin has been proposed to play a pivotal role as a suppressor protein in signaling systems in maintaining of cell homeostasis [7]. The regucalcin gene is located on the X chromosome [8,9]. Interestingly, the map location for a growing number of diseases with a genetic basis is encompassed in human X chromosome, and these are known to include syndromic and non-syndromic forms of X-linked mental retardation and X-linked neuromuscler diseases [9]. Regucalcin is expressed in rat brain neuron, and it is decreased in the cerebral cortex and hippocampus of brain with aging [10,11]. There is growing evidence that regucalcin plays a pivotal role in brain neuronal cell regulation.

English

Paeonia is a phylogenetically and taxonomically complex group. In this study, two chloroplast coding region of the matK and rbcL genes, two intergenic spacers, 5’ trnK-matKand matK-3’ trnK, the ribosomal RNA 18S and 5S genes, and the nuclear ribosomal DNA ITS gene were sequenced to study phylogenetic relationships of four Paeonia species. In the matK coding region, most nucleotide variations pointed at the divergence betweenPaeonia suffruticosa (MO) and other three species, strongly supporting the phylogenetic evolution of section Paeonia and section Moutan in the Paeonia genus; the variable sites ofPaeonia lactiflora CHA1 accession compared to CHA accession were all identical toPaeonia obovata SHAN accession, indicating that CHA1 might be a hybrid result of CHA and SHAN. Another chloroplast coding region, rbcL showed lower variation rate and less phylogenetic information than the matK region in all four Paeonia species investigated in this study, while the 5S rRNA gene and nrDNA ITS region showed higher variation rate. However, combined phylogenetic relationship of all four peony species is more clearer than any single-locus one. This study would provide more sequence sources of peony species and help further understanding of the phylogenetic relationship. Key words: Deoxyribonucleic acid (DNA) barcoding, matK, nuclear ribosomaldeoxyribonucleic acid internal transcribed spacer (nrDNA ITS), Paeonia, phylogeny, ribulose-bisphosphate carboxylase (rbcL), 5S ribosomal ribonucleic acid (rRNA).

Karyotype and nucleic acid content in Zantedeschia aethiopica Spr. and Zantedeschia elliottiana Engl.

Analysis of karyotype, nucleic deoxyribonucleic acid (DNA) content and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were performed in Zantedeschia aethiopica and Zantedeschia elliottiana. Mitotic metaphase in both species showed 2n=32. The chromosomes of both species were quite similar with medium length ranging from 1.55 ± 0.04 to 3.85 ± 0.12 µM in Z. aethiopica and 2.15 ± 0.04 to 3.90 ± 0.12 µM in Z. elliottiana. However, some differences were found in morphology and centromeric position among the chromosomes. Identification of individual chromosomes was carried out using chromosomes length, and centromeric positions. The karyotype of Z. aethiopica was determined to be 2n = 32 = 14 m + 18 sm and of Z. elliottiana to be 2n = 32 = 10 m + 22 sm. The 2C nuclear DNA content was found to be 3.72 ± 0.10 picograms (equivalent to 3638.16 mega base pairs) for Z. aethiopica and 1144.26 ± 0.05 picograms (equivalent to 1144.26 mega base pairs) for Z. elliottiana. Leaf protein analysis showed 11 and 9 bands for Z. aethiopica and Z. elliottiana, respectively, among which some were species specific. These results may provide useful information regarding Zantedeschia for the study of taxonomic relationships, genetics and breeding.

Social Hybridogenesis in the Clonal Ant Cataglyphis hispanica

With a few rare exceptions, the vast majority of animals reproduce sexually. Some species have, however, evolved alternative modes of reproduction by shifting from classical bisexuality to unorthodox reproductive systems, like parthenogenesis, gynogenesis, or hybridogenesis. Under hybridogenesis, both the maternal and paternal genomes are expressed in somatic tissues, whereas the germline is purely maternal. Recently, a form of hybridogenesis at the level of the society has been reported in some ants, where purebred females develop into reproductive queens and interlineage hybrids into sterile workers. Here, we report a unique case of social hybridogenesis in the desert ant Cataglyphis hispanica. Workers are produced exclusively from interbreeding between two distinct genetic lineages, whereas male and female sexuals are produced by asexual reproduction through parthenogenesis. As a consequence, all workers are pure hybridogens, and only maternal genes are perpetuated from one generation to the next. Thus, queens of C. hispanica use sexual reproduction for colony growth, whereas they reproduce asexually through parthenogenesis for germline production.

Identification of Meconopsis species by a DNA barcode sequence: The nuclear internal transcribed spacer (ITS) region of ribosomal deoxyribonucleic acid (DNA)

Deoxyribonucleic acid (DNA) barcoding is a novel technology that uses a standard DNA sequence to facilitate species identification. Species identification is necessary for the authentication of traditional plant based medicines. Although a consensus has not been agreed regarding which DNA sequences can be used as the best plant barcode, the internal transcribed spacer (ITS) region of nuclear ribosomal DNA has been tested and applied extensively in recent years. In this study, we used the ITS region to test its possibility to serve as barcodes for Meconopsis species which are widely used in traditional Tibetan medicines that are used throughout the Himalayas. We sequenced 14 accessions representing four Meconopsis species. The result shows ITS sequences were found to be unique for each species, with the interspecies percentages of nucleotide differences averaging 5.1% and ranging from 0.2 to 9.6%. In contrast, the intraspecies percentages of nucleotide differences among the Meconopsis species studied ranged from 0 to 1.9%. Our results indicate that the ITS region can be used as a barcode to distinguish Meconopsis species.