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Zoology (Jena, Germany) Dec 2022Species of planarians include both asexually reproducing individuals (reproduce through fission and regeneration) and sexually reproducing individuals (hermaphrodites...
Species of planarians include both asexually reproducing individuals (reproduce through fission and regeneration) and sexually reproducing individuals (hermaphrodites that mate to produce cocoons). While some individuals can switch between the asexual and sexual modes of reproduction. In this study, we examined the reproductive modes and ploidy of Dugesia japonica and Dugesia ryukyuensis from three spring wells in Okinawa (Japan) during two consecutive years. D. japonica are mostly asexual and triploid. In contrast, only 40 % of D. ryukyuensis are asexual and triploid; the remaining are sexual, and diploid or triploid. The sexually reproductive season of D. ryukyuensis is winter. In July, the reproductive organs disappear, and the individuals start asexual reproduction through fission and regeneration. In January of the following year, the individuals develop ovaries and necessary reproductive organs and start sexual reproduction. When these species were lab-reared for a longer period, the reproductive cycles in three strains were repeated for three years. These results confirm that D. ryukyuensis population in Okinawa switches between reproductive modes on an annual cycle, even when kept under constant temperature and no light/dark cycle.
Topics: Animals; Planarians; Triploidy; Reproduction; Seasons; Diploidy
PubMed: 36399916
DOI: 10.1016/j.zool.2022.126053 -
The Plant Journal : For Cell and... Apr 2012The study of plant biology in the 21st century is, and will continue to be, vastly different from that in the 20th century. One driver for this has been the use of... (Review)
Review
The study of plant biology in the 21st century is, and will continue to be, vastly different from that in the 20th century. One driver for this has been the use of genomics methods to reveal the genetic blueprints for not one but dozens of plant species, as well as resolving genome differences in thousands of individuals at the population level. Genomics technology has advanced substantially since publication of the first plant genome sequence, that of Arabidopsis thaliana, in 2000. Plant genomics researchers have readily embraced new algorithms, technologies and approaches to generate genome, transcriptome and epigenome datasets for model and crop species that have permitted deep inferences into plant biology. Challenges in sequencing any genome include ploidy, heterozygosity and paralogy, all which are amplified in plant genomes compared to animal genomes due to the large genome sizes, high repetitive sequence content, and rampant whole- or segmental genome duplication. The ability to generate de novo transcriptome assemblies provides an alternative approach to bypass these complex genomes and access the gene space of these recalcitrant species. The field of genomics is driven by technological improvements in sequencing platforms; however, software and algorithm development has lagged behind reductions in sequencing costs, improved throughput, and quality improvements. It is anticipated that sequencing platforms will continue to improve the length and quality of output, and that the complementary algorithms and bioinformatic software needed to handle large, repetitive genomes will improve. The future is bright for an exponential improvement in our understanding of plant biology.
Topics: Algorithms; Computational Biology; Epigenomics; Genome Size; Genome, Plant; Genomics; Plants; Ploidies; Sequence Analysis, DNA; Software; Transcriptome
PubMed: 22449051
DOI: 10.1111/j.1365-313X.2012.04894.x -
Molecular Biology of the Cell Aug 2022Cells adopt a size that is optimal for their function, and pushing them beyond this limit can cause cell aging and death by senescence or reduce proliferative potential....
Cells adopt a size that is optimal for their function, and pushing them beyond this limit can cause cell aging and death by senescence or reduce proliferative potential. However, by increasing their genome copy number (ploidy), cells can increase their size dramatically and homeostatically maintain physiological properties such as biosynthesis rate. Recent studies investigating the relationship between cell size and rates of biosynthesis and metabolism under normal, polyploid, and pathological conditions are revealing new insights into how cells attain the best function or fitness for their size by tuning processes including transcription, translation, and mitochondrial respiration. A new frontier is to connect single-cell scaling relationships with tissue and whole-organism physiology, which promises to reveal molecular and evolutionary principles underlying the astonishing diversity of size observed across the tree of life.
Topics: Biological Evolution; Cell Size; Humans; Mitochondria; Ploidies; Polyploidy
PubMed: 35862496
DOI: 10.1091/mbc.E21-12-0627 -
Cytometry. Part a : the Journal of the... Sep 2022The estimation of nuclear DNA content has been by far the most popular application of flow cytometry in plants. Because flow cytometry measures relative fluorescence... (Review)
Review
The estimation of nuclear DNA content has been by far the most popular application of flow cytometry in plants. Because flow cytometry measures relative fluorescence intensities of nuclei stained by a DNA fluorochrome, ploidy determination, and estimation of the nuclear DNA content in absolute units both require comparison to a reference standard of known DNA content. This implies that the quality of the results obtained depends on the standard selection and use. Internal standardization, when the nuclei of an unknown sample and the reference standard are isolated, stained, and measured simultaneously, is mandatory for precise measurements. As DNA peaks representing G /G nuclei of the sample and standard appear on the same histogram of fluorescence intensity, the quotient of their position on the fluorescence intensity axis provides the quotient of DNA amounts. For the estimation of DNA amounts in absolute units, a number of well-established standards are now available to cover the range of known plant genome sizes. Since there are different standards in use, the standard and the genome size assigned to it has always to be reported. When none of the established standards fits, the introduction of a new standard species is needed. For this purpose, the regression line approach or simultaneous analysis of the candidate standard with several established standards should be prioritized. Moreover, the newly selected standard organism has to fulfill a number of requirements: it should be easy to identify and maintain, taxonomically unambiguous, globally available, with known genome size stability, lacking problematic metabolites, suitable for isolation of sufficient amounts of nuclei, and enabling measurements with low coefficients of variation of DNA peaks, hence suitable for the preparation of high quality samples.
Topics: DNA, Plant; Flow Cytometry; Genome, Plant; Ploidies; Reference Standards
PubMed: 34405937
DOI: 10.1002/cyto.a.24495 -
Biology Letters Dec 2022Whole-genome duplication is a common mutation in eukaryotes with far-reaching phenotypic effects, the resulting morphological and fitness consequences and how they... (Meta-Analysis)
Meta-Analysis
Whole-genome duplication is a common mutation in eukaryotes with far-reaching phenotypic effects, the resulting morphological and fitness consequences and how they affect the survival of polyploid lineages are intensively studied. Another important factor may also determine the probability of establishment and success of polyploid lineages: inbreeding depression. Inbreeding depression is expected to play an important role in the establishment of neopolyploid lineages, their capacity to colonize new environments, and in the simultaneous evolution of ploidy and other life-history traits such as self-fertilization. Both theoretically and empirically, there is no consensus on the consequences of polyploidy on inbreeding depression. In this meta-analysis, we investigated the effect of polyploidy on the evolution of inbreeding depression, by performing a meta-analysis within angiosperm species. The main results of our study are that the consequences of polyploidy on inbreeding depression are complex and depend on the time since polyploidization. We found that young polyploid lineages have a much lower amount of inbreeding depression than their diploid relatives and their established counterparts. Natural polyploid lineages are intermediate and have a higher amount of inbreeding depression than synthetic neopolyploids, and a smaller amount than diploids, suggesting that the negative effect of polyploidy on inbreeding depression decreases with time since polyploidization.
Topics: Inbreeding Depression; Polyploidy; Diploidy; Inbreeding; Magnoliopsida
PubMed: 36514955
DOI: 10.1098/rsbl.2022.0477 -
Nucleus (Austin, Tex.) Dec 2023In adult mammals, many heart muscle cells (cardiomyocytes) are polyploid, do not proliferate (post-mitotic), and, consequently, cannot contribute to heart regeneration.... (Review)
Review
In adult mammals, many heart muscle cells (cardiomyocytes) are polyploid, do not proliferate (post-mitotic), and, consequently, cannot contribute to heart regeneration. In contrast, fetal and neonatal heart muscle cells are diploid, proliferate, and contribute to heart regeneration. We have identified interdependent changes of the nuclear lamina, nuclear pore complexes, and DNA-content (ploidy) in heart muscle cell maturation. These results offer new perspectives on how cells alter their nuclear transport and, with that, their gene regulation in response to extracellular signals. We present how changes of the nuclear lamina alter nuclear pore complexes in heart muscle cells. The consequences of these changes for cellular regeneration and stress response in the heart are discussed.
Topics: Animals; Nuclear Pore; Nuclear Lamina; Ploidies; Cell Differentiation; Lamins; Mammals
PubMed: 37606283
DOI: 10.1080/19491034.2023.2246310 -
Nature Communications Oct 2022Ploidy changes are frequent in nature and contribute to evolution, functional specialization and tumorigenesis. Analysis of model organisms of different ploidies...
Ploidy changes are frequent in nature and contribute to evolution, functional specialization and tumorigenesis. Analysis of model organisms of different ploidies revealed that increased ploidy leads to an increase in cell and nuclear volume, reduced proliferation, metabolic changes, lower fitness, and increased genomic instability, but the underlying mechanisms remain poorly understood. To investigate how gene expression changes with cellular ploidy, we analyzed isogenic series of budding yeasts from 1N to 4N. We show that mRNA and protein abundance scales allometrically with ploidy, with tetraploid cells showing only threefold increase in protein abundance compared to haploids. This ploidy-dependent sublinear scaling occurs via decreased rRNA and ribosomal protein abundance and reduced translation. We demonstrate that the activity of Tor1 is reduced with increasing ploidy, which leads to diminished rRNA gene repression via a Tor1-Sch9-Tup1 signaling pathway. mTORC1 and S6K activity are also reduced in human tetraploid cells and the concomitant increase of the Tup1 homolog Tle1 downregulates the rDNA transcription. Our results suggest that the mTORC1-Sch9/S6K-Tup1/TLE1 pathway ensures proteome remodeling in response to increased ploidy.
Topics: Humans; Proteome; Tetraploidy; Haploidy; Transcription Factors; RNA, Ribosomal; Ribosomal Proteins; DNA, Ribosomal; Mechanistic Target of Rapamycin Complex 1; RNA, Messenger
PubMed: 36261409
DOI: 10.1038/s41467-022-33904-7 -
Microbiology Spectrum Jul 2017The ability of an organism to replicate and segregate its genome with high fidelity is vital to its survival and for the production of future generations. Errors in... (Review)
Review
The ability of an organism to replicate and segregate its genome with high fidelity is vital to its survival and for the production of future generations. Errors in either of these steps (replication or segregation) can lead to a change in ploidy or chromosome number. While these drastic genome changes can be detrimental to the organism, resulting in decreased fitness, they can also provide increased fitness during periods of stress. A change in ploidy or chromosome number can fundamentally change how a cell senses and responds to its environment. Here, we discuss current ideas in fungal biology that illuminate how eukaryotic genome size variation can impact the organism at a cellular and evolutionary level. One of the most fascinating observations from the past 2 decades of research is that some fungi have evolved the ability to tolerate large genome size changes and generate vast genomic heterogeneity without undergoing canonical meiosis.
Topics: Aneuploidy; Evolution, Molecular; Fungi; Genetic Variation; Genome, Fungal; Ploidies; Polyploidy
PubMed: 28752816
DOI: 10.1128/microbiolspec.FUNK-0051-2016 -
Cellular and Molecular Gastroenterology... 2020
Topics: Diploidy; Gene Expression Profiling; Hepatocytes; Humans; Ploidies; Polyploidy; Stem Cells; Transcriptome
PubMed: 31654613
DOI: 10.1016/j.jcmgh.2019.09.008 -
Current Protocols in Microbiology Aug 2018Ploidy, the number of sets of homologous chromosomes in a cell, can alter cellular physiology, gene regulation, and the spectrum of acquired mutations. Advances in...
Ploidy, the number of sets of homologous chromosomes in a cell, can alter cellular physiology, gene regulation, and the spectrum of acquired mutations. Advances in single-cell flow cytometry have greatly improved the understanding of how genome size contributes to diverse biological processes including speciation, adaptation, pathogenesis, and tumorigenesis. For example, fungal pathogens can undergo whole genome duplications during infection of the human host and during acquisition of antifungal drug resistance. Quantification of ploidy is dramatically affected by the nucleic acid staining technique and the flow cytometry analysis of single cells. Ploidy in fungi is also impacted by samples that are heterogeneous for both ploidy and morphology, and control strains with known ploidy must be included in every flow cytometry experiment. To detect ploidy changes within fungal strains, the following protocol was developed to accurately and dependably interrogate single-cell ploidy. © 2018 by John Wiley & Sons, Inc.
Topics: Flow Cytometry; Fungi; Humans; Mycology; Mycoses; Ploidies; Software; Staining and Labeling
PubMed: 30028911
DOI: 10.1002/cpmc.58