Genome sequence of the wild species, Spinacia tetrandra, including a phased sequence of the extensive sex‐linked region, revealing partial degeneration in evolutionary strata with unusual properties DOI
Hongbing She, Zhiyuan Liu, Zhaosheng Xu

et al.

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

Summary Genetic degeneration is a striking feature of Y chromosomes, often involving losses many genes carried on the X chromosome. However, time course gene remains unclear. Sex chromosomes plants evolved more recently than animals' highly degenerated ones, making them ideal for studying timing. To investigate Spinacia sex chromosome evolution and degeneration, we compared genome sequences cultivated oleracea , with small Y‐linked region Chr4, its two wild relatives. In spinach closest relative turkestanica duplication (YDR) introduced male‐determining factor into Chr4's low‐recombining pericentromeric region. other words, turnover event occurred in these species' recent common ancestor. The homologous Chr4 distantly related S. tetrandra has c . 133 Mb completely sex‐linked partially region, possibly reflecting ancestral state. Sequence divergence analysis suggests that ‘evolutionary strata’ shortly before lineages split. Consistent hypothesis, YDR species not within older stratum. We discuss unexpected findings genetic genomic rearrangements, repetitive sequence density are all greatest younger

Language: Английский

Does chromoanagenesis play a role in the origin of B chromosomes? DOI Creative Commons
Andreas Houben, Jörg Fuchs, Ali Mohammad Banaei‐Moghaddam

et al.

Heredity, Journal Year: 2025, Volume and Issue: unknown

Published: April 19, 2025

Abstract B chromosomes (Bs) exist in addition to the standard (A) a wide range of species. The process underlying their origin is still unclear. We propose pathways intra- and interspecific based on known mechanisms chromosome evolution available knowledge sequence composition different speculate that mitotic or meiotic segregation error one more A initiates, via chromoanagenesis, formation proto-B chromosome. In second step, accumulate chromosome- organelle-derived sequences over time, most likely DNA double-strand break (DSB) mis-repair. Consequently, original structure early stage becomes masked by continuous incorporation. similarity between integrated into donor decreases time if there no selection pressure these chromosomes. However, besides also other leading might exist.

Language: Английский

Citations

0

Genome sequence of the wild species, Spinacia tetrandra, including a phased sequence of the extensive sex‐linked region, revealing partial degeneration in evolutionary strata with unusual properties DOI
Hongbing She, Zhiyuan Liu, Zhaosheng Xu

et al.

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

Summary Genetic degeneration is a striking feature of Y chromosomes, often involving losses many genes carried on the X chromosome. However, time course gene remains unclear. Sex chromosomes plants evolved more recently than animals' highly degenerated ones, making them ideal for studying timing. To investigate Spinacia sex chromosome evolution and degeneration, we compared genome sequences cultivated oleracea , with small Y‐linked region Chr4, its two wild relatives. In spinach closest relative turkestanica duplication (YDR) introduced male‐determining factor into Chr4's low‐recombining pericentromeric region. other words, turnover event occurred in these species' recent common ancestor. The homologous Chr4 distantly related S. tetrandra has c . 133 Mb completely sex‐linked partially region, possibly reflecting ancestral state. Sequence divergence analysis suggests that ‘evolutionary strata’ shortly before lineages split. Consistent hypothesis, YDR species not within older stratum. We discuss unexpected findings genetic genomic rearrangements, repetitive sequence density are all greatest younger

Language: Английский

Citations

0