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An updated explanation of ancestral karyotype changes and reconstruction of evolutionary trajectories to form Camelina sativa chromosomes.

ABSTRACT: BACKGROUND:Belonging to lineage I of Brassicaceae, Camelina sativa is formed by two hybridizations of three species (three sub-genomes). The three sub-genomes were diverged from a common ancestor, likely derived from lineage I (Ancestral Crucifer karyotype, ACK). The karyotype evolutionary trajectories of the C. sativa chromosomes are currently unknown. Here, we managed to adopt a telomere-centric theory proposed previously to explain the karyotype evolution in C. sativa. RESULTS:By characterizing the homology between A. lyrata and C. sativa chromosomes, we inferred ancestral diploid karyotype of C. sativa (ADK), including 7 ancestral chromosomes, and reconstructed the evolutionary trajectories leading to the formation of extant C. sativa genome. The process involved 2 chromosome fusions. We found that sub-genomes Cs-G1 and Cs-G2 may share a closer common ancestor than Cs-G3. Together with other lines of evidence from Arabidopsis, we propose that the Brassicaceae plants, even the eudicots, follow a chromosome fusion mechanism favoring end-end joining of different chromosomes, rather than a mechanism favoring the formation circular chromosomes and nested chromosome fusion preferred by the monocots. CONCLUSIONS:The present work will contribute to understanding the formation of C. sativa chromosomes, providing insight into Brassicaceae karyotype evolution.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC7549213 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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An updated explanation of ancestral karyotype changes and reconstruction of evolutionary trajectories to form Camelina sativa chromosomes.

Zhang Zhikang Z Meng Fanbo F Sun Pengchuan P Yuan Jiaqing J Gong Ke K Liu Chao C Wang Weijie W Wang Xiyin X

BMC genomics 20201012 1

<h4>Background</h4>Belonging to lineage I of Brassicaceae, Camelina sativa is formed by two hybridizations of three species (three sub-genomes). The three sub-genomes were diverged from a common ancestor, likely derived from lineage I (Ancestral Crucifer karyotype, ACK). The karyotype evolutionary trajectories of the C. sativa chromosomes are currently unknown. Here, we managed to adopt a telomere-centric theory proposed previously to explain the karyotype evolution in C. sativa.<h4>Results</h4> ...[more]

PMID: 33045990

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An updated explanation of ancestral karyotype changes and reconstruction of evolutionary trajectories to form Camelina sativa chromosomes.

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An updated explanation of ancestral karyotype changes and reconstruction of evolutionary trajectories to form Camelina sativa chromosomes.

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