ABSTRACT As environments worldwide change at unprecedented rates during the Anthropocene, understanding context dependency—how species interactions vary depending on environmental context—is crucial. Combining comparative genomics across 42 angiosperms with transcriptomics, genome‐wide association mapping and gene duplication origin analyses, we show for the first time that gene family expansions are important to context‐dependent regulation of species interactions. Gene families expanded in mycorrhizal fungi‐associating plants display up to 200% more context‐dependent gene expression and double the genetic variation associated with mycorrhizal benefits to plant fitness. Moreover, we discover these gene family expansions arise primarily from tandem duplications with > 2‐times more tandem duplications genome‐wide, indicating gene family expansions continuously supply genetic variation, allowing fine‐tuning of context dependency in species interactions throughout plant evolution. Taken together, our results spotlight how widespread gene duplications can provide molecular flexibility required for plant–microbial interactions to match changing environmental conditions.
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Coexpression enhances cross-species integration of single-cell RNA sequencing across diverse plant species
Abstract Single-cell RNA sequencing is increasingly used to investigate cross-species differences driven by gene expression and cell-type composition in plants. However, the frequent expansion of plant gene families due to whole-genome duplications makes identification of one-to-one orthologues difficult, complicating integration. Here we demonstrate that coexpression can be used to trim many-to-many orthology families down to identify one-to-one gene pairs with proxy expression profiles, improving the performance of traditional integration methods and reducing barriers to integration across a diverse array of plant species.
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- Award ID(s):
- 1934388
- PAR ID:
- 10567492
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Plants
- Volume:
- 10
- Issue:
- 7
- ISSN:
- 2055-0278
- Page Range / eLocation ID:
- 1075 to 1080
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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