Plant Cytogenetics in the Micronuclei Investigation—The Past, Current Status, and Perspectives

Abstract

Cytogenetic approaches play an essential role as a quick evaluation of the first genetic effects after mutagenic treatment. Although labor-intensive and time-consuming, they are essential for the analyses of cytotoxic and genotoxic effects in mutagenesis and environmental monitoring. Over the years, conventional cytogenetic analyses were a part of routine laboratory testing in plant genotoxicity. Among the methods that are used to study genotoxicity in plants, the micronucleus test particularly represents a significant force. Currently, cytogenetic techniques go beyond the simple detection of chromosome aberrations. The intensive development of molecular biology and the significantly improved microscopic visualization and evaluation methods constituted significant support to traditional cytogenetics. Over the past years, distinct approaches have allowed an understanding the mechanisms of formation, structure, and genetic activity of the micronuclei. Although there are many studies on this topic in humans and animals, knowledge in plants is significantly limited. This article provides a comprehensive overview of the current knowledge on micronuclei characteristics in plants. We pay particular attention to how the recent contemporary achievements have influenced the understanding of micronuclei in plant cells. Together with the current progress, we present the latest applications of the micronucleus test in mutagenesis and assess the state of the environment.

Comet Assay: Multifaceted Options for Studies of Plant Stress Response

“…TUNEL assays provide an estimation of the extent of double DNA strand breaks but cannot determine the size of the cleaved products, as the localization of nuclear DNA fragmentation is performed in situ in fixed cells and tissues. The resolution of TUNEL assays allows for the detection of DNA breaks in a single nucleus with the possible analysis of specific localization within it; the assay is fast and relatively easy to carry out (reviewed in [78]).…”

Nanomaterials Induced Genotoxicity in Plant: Methods and Strategies

“…Among the major effects observed from the exogenous genotoxic effects on plant genomes, the chromosomal aberrations, which are the result of structural and numerical chromosome changes, preferentially within heterochromatic regions, are composed mainly of repetitive DNA sequences [ 21 ]. Optical, fluorescence and confocal laser scanning microscopy techniques are able to highlight aberrations at the level of the chromosome structure, including chromosomal breaks, sticky, multipolar, and laggard chromosomes, as well as micronucleus formation [ 22 , 23 , 24 ].…”

Unraveling the DNA Methylation in the rDNA Foci in Mutagen-Induced Brachypodium distachyon Micronuclei

“…Micronuclei (MN) are small outside-nuclear bodies located next to the interphase nucleus. They can arise from acentric chromosome fragments due to single- and double-strand breaks in DNA or from entire chromosomes due to the action of a mutagenic agent on the microtubules [ 7 ].…”

“…Maleic acid hydrazide (MH) is a commonly used chemical mutagen in plant mutagenesis [ 7 ]. MH is a uracil isomer that integrates into DNA and inhibits DNA synthesis, although the exact mechanism of its action is still not well understood.…”