Impact of repetitive DNA on sex chromosome evolution in plants

Abstract

Structurally and functionally diverged sex chromosomes have evolved in many animals as well as in some plants. Sex chromosomes represent a specific genomic region(s) with locally suppressed recombination. As a consequence, repetitive sequences involving transposable elements, tandem repeats (satellites and microsatellites), and organellar DNA accumulate on the Y (W) chromosomes. In this paper, we review the main types of repetitive elements, their gathering on the Y chromosome, and discuss new findings showing that not only accumulation of various repeats in non-recombining regions but also opposite processes form Y chromosome. The aim of this review is also to discuss the mechanisms of repetitive DNA spread involving (retro) transposition, DNA polymerase slippage or unequal crossing-over, as well as modes of repeat removal by ectopic recombination. The intensity of these processes differs in non-recombining region(s) of sex chromosomes when compared to the recombining parts of genome. We also speculate about the relationship between heterochromatinization and the formation of heteromorphic sex chromosomes.

Identification of sex‐specific markers and heterogametic XX/XY sex determination system by 2b‐RAD sequencing in redtail catfish (Mystus wyckioides)

“…Transposon activity played important roles in genome and sex chromosome evolution, and transposon translocation between different chromosomes of the same genome or between different genomes can cause chromosome breakage, deletion and rearrangements (Faber-Hammond, Phillips, & Brown, 2015;Fontdevila, 1992;O'Neill, O'Neill, & Graves, 1998;Singh et al, 2014). Sex chromosomes originated from a pair of autosomes and evolved from the homomorphic (Charlesworth, Charlesworth, & Marais, 2005;Haldane, 1922;Hobza et al, 2015;Na, Wang, & Ming, 2014). From an evolutionary point of view, transposable elements have recently been recognized as important factors in the formation of gene regulatory networks.…”

“…The DL 2000 DNA marker sizes are shown on the left chromosomes to heteromorphic, which may lead to recombination suppression and it was the crucial step in sex chromosome evolution(Hobza et al, 2015;Natri, Shikano, & Merila 2013). (a) The 351 bp Y-specific fragment amplified by the Y-specific primer pair 18-Fy and 18-Ry only in male individuals.…”

“…PCR amplification results in 27 males and 27 females of ref189950. The morphological and structural differentiation of sex chromosomes was mostly caused by the accumulation of repetitive DNA because sex-specific regulatory functions of transposable elements may lead to differential repeat sequence content of the X and Y chromosomes, therefore, the large distribution of transposable element in non-recombinant regions can rapidly regulate the expression pattern of the entire Y (W) chromosome and make the chromosome gradually silent and degenerate into heterochromatic(Charlesworth, Charlesworth, & Marais, 2005;Haldane, 1922;Hobza et al, 2015;Na, Wang, & Ming, 2014). (b)The 190 bp X-specific fragment amplified by the X-specific primer pair 18-Fx and 18-Rx in all individuals, and dosage effect was observed between females and males.…”

Karyotype analysis in Bignonieae (Bignoniaceae): chromosome numbers and heterochromatin

“…Chromosome type E was the rarest, being observed only in Fridericia pubescens. The variations of the numbers and placements of heterochromatic bands may reflect satellite DNA amplification, retrotransposons, and co-amplification of tandem repeats, and/or other transposable elements (Eickbush and Eickbush 2007, Hobza et al 2015, Evtushenko et al 2016. Despite the multitude of mechanisms capable of producing different patterns, variations in heterochromatin patterns have been used to confirm the taxonomic placements of numerous taxa.…”

Sex chromosome repeats tip the balance towards speciation

“…For example, despite shared satellites at centromere loci across autosomes, the distribution of satellites varies across the X and Y chromosomes of wallabies (Bulazel, Ferreri, Eldridge, & O'Neill, ) (Figure ). Examples of novel transposable element and/or satellite distribution across sex chromosomes have been reported in many systems, including plants (Charlesworth, ; Cunado et al., ; Hobza et al., , ; Mariotti, Manzano, Kejnovsky, Vyskot, & Jamilena, ; Mariotti et al., ; Navajas‐Pérez et al., ; Shibata, Hizume, & Kuroki, , ; Steflova et al., ; Vyskot & Hobza, ), insects (Blackmon, Ross, & Bachtrog, ; DiBartolomeis, Tartof, & Jackson, ; Khost et al., ; Kuhn & Heslop‐Harrison, ; Palacios‐Gimenez et al., ; Steinemann & Steinemann, ) and vertebrates (Bulazel et al., ; Cioffi, Camacho, & Bertollo, ; Cioffi, Kejnovsky, & Bertollo, ; Cioffi, Molina, Moreira‐Filho, & Bertollo, ; Delany, Gessaro, Rodrigue, & Daniels, ; Ezaz & Deakin, ; Forster et al., ; Kawai et al., ; Kortschak, Tsend‐Ayush, & Grutzner, ; Macdonald et al., ; Miyaki, Hanotte, Wajntal, & Burke, ; Murtagh et al., ; de Oliveira et al., ; Pokorna, Kratochvil, & Kejnovsky, ; Suda, Uno, Mori, Matsuda, & Nakamura, ; Tomaszkiewicz, Medvedev, & Makova, ; Tone, Sakaki, Hashiguchi, & Mizuno, ; Wilson & Makova, ,b; Young, O'Meally, Sarre, Georges, & Ezaz, ), including human (Lander et al., ; Miga et al., ; Ross et al., ; Skaletsky et al., ).…”