Two chromosomal structures, known as monocentric and holocentric chromosomes, have evolved in eukaryotes. Acentric fragments of monocentric chromosomes are unequally distributed to daughter cells and/or lost, while holocentric fragments are inherited normally. In monocentric species, unequal distribution should generate chimeras of cells with different nuclear DNA content. We investigated whether such differences in monocentric species are detectable by flow cytometry (FCM) as (i) a decreased nuclear DNA content and (ii) an increased coefficient of variance (CV) of the G1 peak after gamma radiation-induced fragmentation. We compared 13 monocentric and 9 holocentric plant species. Unexpectedly, monocentrics and holocentrics did not differ with respect to parameters (i) and (ii) in their response to gamma irradiation. However, we found that the proportion of G2 nuclei was highly elevated in monocentrics after irradiation, while holocentrics were negligibly affected. Therefore, we hypothesize that DNA-damaging agents induce cell cycle arrest leading to endopolyploidy only in monocentric and not (or to much lesser extent) in holocentric plants. While current microscope-dependent methods for holocentrism detection are unreliable for small and numerous chromosomes, which are common in holocentrics, FCM can use somatic nuclei. Thus, FCM may be a rapid and reliable method of high-throughput screening for holocentric candidates across plant phylogeny.

Department of Botany and Zoology Masaryk University Kotlarska 2 611 37 Brno Czech Republic

Erratum v

Sci Rep. 2017 Jun 30;7:46869. doi: 10.1038/srep46869. PubMed

Zobrazit více v PubMed

Melters D. P., Paliulis L. V., Korf I. F. & Chan S. W. Holocentric chromosomes: convergent evolution, meiotic adaptations, and genomic analysis. Chromosome Res. 20, 579–593 (2012). PubMed

Bureš P., Zedek F. & Marková M. Plant Genome Diversity Volume 2. (eds Leitch I.

Nordenskiöld H. A study of meiosis in progeny of x-irradiated Luzula purpurea. Hereditas 49, 33–47 (1963).

Sheikh S. A., Kondo K. & Hoshi Y. Study of diffused centromeric nature of Drosera chromosomes. Cytologia 60, 43–47 (1995).

Stear J. & Roth M. Characterization of HCP-6, a C. elegans protein required to prevent chromosome twisting and merotelic attachment. Genes Dev. 16, 1498–1508 (2002). PubMed PMC

Lowden M., Flibotte S., Moerman D. & Ahmed S. DNA synthesis generates terminal duplications that seal end-to-end chromosome fusions. Science 332, 468–471 (2011). PubMed PMC

Jankowska M. PubMed DOI

Nokkala S., Kuznetsova V., Maryanska-Nadachowska A. & Nokkala C. Holocentric chromosomes in meiosis. I. Restriction of the number of chiasmata in bivalents. Chromosome Res. 12, 733–739 (2004). PubMed

Heckmann S. & Houben A. Plant centromere biology (eds Jiang J. & Birchler J. A.) Holokinetic centromeres, 83–94 (Wiley-Blackwell, Oxford, UK 2013).

Lukhtanov V. PubMed

d’Alençon E. PubMed PMC

Zedek F., Šmerda J., Šmarda P. & Bureš P. Correlated evolution of LTR retrotransposons and genome size in the genus Eleocharis. BMC Plant Biol. 10, 265 (2010). PubMed PMC

Lipnerová I., Bureš P., Horová L. & Šmarda P. Evolution of genome size in PubMed PMC

Escudero M. PubMed

Marques A. PubMed PMC

Davey J. W. PubMed DOI PMC

Escudero M., Hipp A. L., Hansen T. F., Voje K. L. & Luceño M. Selection and inertia in the evolution of holocentric chromosomes in sedges ( PubMed

Zedek F. & Bureš P. Evidence for centromere drive in the holocentric chromosomes of Caenorhabditis. PLoS One 7, e30496 (2012). PubMed PMC

Bureš P. & Zedek F. Holokinetic drive: Centromere drive in chromosomes without centromeres. Evolution 68, 2412–2420 (2014). PubMed

Traut W., Sahara K. & Marec F. Sex chromosomes and sex determination in Lepidoptera. Sex Dev. 1, 332–346 (2007). PubMed

Sahara K., Yoshido A. & Traut W. Sex chromosome evolution in moths and butterflies. Chromosome Res. 20, 83–94 (2012). PubMed

Šíchová J. DOI

Nordenskiöld H. Tetrad analysis and the course of meiosis in three hybrids of Luzula campestris. Hereditas 47, 203–238 (1961).

Mavarez J. PubMed

Lukhtanov V. A., Shapoval N. A., Anokhin B. A., Saifitdinova A. F. & Kuznetsova V. G. Homoploid hybrid speciation and genome evolution via chromosome sorting. Proc. Biol. Sci. 22, 282(1807) (2015). PubMed PMC

Mola L. M. & Papeschi A. G. Holokinetic chromosomes at a glance. J. Basic Appl. Genet. 17, 17–33 (2006).

Eichenlaub-Ritter U. & Ruthmann A. Holokinetic composite chromosomes with “diffuse” kinetochores in the micronuclear mitosis of a heterotrichous ciliate. Chromosoma 84, 701–716 (1982).

Godward M. B. E. The Chromosomes of the Algae (ed. Godward M. B. E.) Conjugales, 24–51 (Edward Arnold, London, 1966).

Wrensch D. L., Kethley J. B. & Norton R. A. Mites: Ecological and Evolutionary Analyses of Life-Story Patterns (ed. Houck M. A.) Cytogenetics of holokinetic chromosomes and inverted meiosis: keys to the evolutionary success of mites, with generalizations on eukaryotes, 282–342 (Chapman and Hall, New York, 1994).

Guerra M. PubMed

Otto F. J. & Oldiges H. Flow cytogenetic studies in chromosomes and whole cells for the detection of clastogenic effects. Cytometry 1, 13–17 (1980). PubMed

Otto F. J., Oldiges H., Göhde W. & Jain V. K. Flow cytometric measurement of nuclear DNA content variations as a potential PubMed

McMurphy L. M. & Rayburn A. L. Nuclear alterations of maize plants grown in soil contaminated with coal fly ash. Arch. Environ. Con. Tox. 25, 520–524 (1993).

Rayburn A. L. & Wetzel J. B. Flow Cytometric Analyses of Intraplant Nuclear DNA Content Variation Induced by Sticky Chromosomes. Cytometry 49, 36–41 (2002). PubMed

Yamaguchi H.

Kahrizi Z. A., Kermani M. J. & Amiri M. Effect of gamma rays on nuclear DNA content in different rose genotypes. Int. Res. J. Appl. Basic Sci. 3, 1155–1160 (2012).

Šmarda P. PubMed PMC

Šmarda P. & Bureš P. Understanding intraspecific variation in genome size in plants. Preslia 82, 41–61 (2010).

Otto F. Methods in cell biology Vol. 33 (eds Crissman H. A. & Darzynkiewicz Z.) DAPI staining of fixed cells for high-resolution flow cytometry of nuclear DNA, 105–110 (Academic Press New York, NY, 1990).

Šmarda P., Bureš P., Šmerda J. & Horová L. Measurements of genomic GC content in plant genomes with flow cytometry: A test for reliability. New Phytol. 193, 513–521 (2012). PubMed

Doležel J., Greilhuber J. & Suda J. Estimation of nuclear DNA content in plants using flow cytometry. Nat. Protoc. 2, 2233–2244 (2007). PubMed

Kynast R. G., Joseph J. A., Pellicer J., Ramsay M. M. & Rudall P. J. Chromosome behavior at the base of the angiosperm radiation: karyology of PubMed

Ivanov A. PubMed

Erenpreisa J., Cragg M. S., Salmina K., Hausmann M. & Scherthan H. The role of meiotic cohesin REC8 in chromosome segregation in gamma irradiation-induced endopolyploid tumour cells. Exp. Cell Res. 315, 2593–2603 (2009). PubMed

Mirzayans R., Andrais B., Scott A., Wang Y. W. & Murray D. Ionizing radiation-induced responses in human cells with differing TP53 status. Int. J. Mol. Sci. 14, 22409–22435 (2013). PubMed PMC

Adachi S. PubMed PMC

Gegas V. C. PubMed PMC

Yamasaki S., Shimada E., Kuwano T., Kawano T. & Noguchi N. Continuous UV-B irradiation induces endoreduplication and peroxidase activity in epidermal cells surrounding trichomes on cucumber cotyledons. J. Radiat. Res. 51, 187–196 (2010). PubMed

Evans L. S. Cell Cycle Kinetics of Endoreduplication in Gamma-Irradiated Root Meristems of Pisum sativum. Am. J. Bot. 65, 1084–1090 (1978).

Yoshiyama K. O., Sakaguchi K. & Kimura S. DNA damage response in plants: conserved and variable response compared to animals. Biology (Basel) 2, 1338–1356 (2013). PubMed PMC

Barow M. Endopolyploidy in seed plants. BioEssays 28, 271–281 (2006). PubMed

Chromosome size matters: genome evolution in the cyperid clade

Holocentric Chromosomes Probably Do Not Prevent Centromere Drive in Cyperaceae

Endopolyploidy is a common response to UV-B stress in natural plant populations, but its magnitude may be affected by chromosome type

Holocentric chromosomes: from tolerance to fragmentation to colonization of the land

Evolution of genome size and genomic GC content in carnivorous holokinetics (Droseraceae)

Absence of positive selection on CenH3 in Luzula suggests that holokinetic chromosomes may suppress centromere drive