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In the past decade, advances in genome sequencing have allowed researchers to uncover the history of hybridization in diverse groups of species, including our own. Although the field has made impressive progress in documenting the extent of natural hybridization, both historical and recent, there are still many unanswered questions about its genetic and evolutionary consequences. Recent work has suggested that the outcomes of hybridization in the genome may be in part predictable, but many open questions about the nature of selection on hybrids and the biological variables that shape such selection have hampered progress in this area. We synthesize what is known about the mechanisms that drive changes in ancestry in the genome after hybridization, highlight major unresolved questions, and discuss their implications for the predictability of genome evolution after hybridization.
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Widespread application of apomixis in agriculture requires further study of natural apomicts
Apomixis, or asexual reproduction through seeds, is frequent in nature but does not exist in any major crop species – yet the phenomenon has captivated researchers for decades given its potential for clonal seed production and plant breeding. A discussion on whether this field will benefit from the continued study of natural apomicts is warranted given the recent outstanding progress in engineering apomixis. Here, we summarize what is known about its genetic control and the status of applying synthetic apomixis in agriculture. We argue there is still much to be learned from natural apomicts, and learning from them is necessary to improve on current progress and guarantee the effective application of apomixis beyond the few genera it has shown promise in so far. Specifically, we stress the value of studying the repeated evolution of natural apomicts in a phylogenetic and comparative -omics context. Finally, we identify outstanding questions in the field and discuss how technological advancements can be used to help close these knowledge gaps. In particular, genomic resources are lacking for apomicts, and this must be remedied for widespread use of apomixis in agriculture.
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- PAR ID:
- 10533922
- Publisher / Repository:
- NSF-PAR
- Date Published:
- Journal Name:
- iScience
- ISSN:
- 2589-0042
- Page Range / eLocation ID:
- 110720
- Subject(s) / Keyword(s):
- plant reproduction asexual seed production synthetic apomixis parthenogenesis convergent evolution comparative genomics
- Format(s):
- Medium: X Size: 3.7
- Size(s):
- 3.7
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.isci.2024.110720
