Abstract Cysteine-rich receptor-like-kinases (CRKs), a transmembrane subfamily of receptor-like kinase, play crucial roles in plant adaptation. As such cotton is the major source of fiber for the textile industry, but environmental stresses are limiting its growth and production. Here, we have performed a deep computational analysis ofCRKsin fiveGossypiumspecies, includingG. arboreum(60 genes), G. raimondii(74 genes), G. herbaceum(65 genes), G. hirsutum(118 genes), andG. barbadense(120 genes). All identified CRKs were classified into 11 major classes and 43 subclasses with the finding of several novel CRK-associated domains includingALMT, FUSC_2, Cript, FYVE,andPkinase. Of these,DUF26_DUF26_Pkinase_Tyrwas common and had elevated expression under different biotic and abiotic stresses. Moreover, the 35 land plants comparison identified several newCRKsdomain-architectures. Likewise, several SNPs and InDels were observed in CLCuD resistantG. hirsutum. The miRNA target side prediction and their expression profiling in different tissues predictedmiR172as a major CRK regulating miR. The expression profiling ofCRKsidentified multiple clusters with co-expression under certain stress conditions. The expression analysis under CLCuD highlighted the role ofGhCRK057, GhCRK059, GhCRK058, and GhCRK081in resistant accession. Overall, these results provided primary data for future potential functional analysis as well as a reference study for other agronomically important crops.
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Genome-wide chromatin accessibility analysis unveils open chromatin convergent evolution during polyploidization in cotton
Allopolyploidization, resulting in divergent genomes in the same cell, is believed to trigger a “genome shock”, leading to broad genetic and epigenetic changes. However, little is understood about chromatin and gene-expression dynamics as underlying driving forces during allopolyploidization. Here, we examined the genome-wide DNase I-hypersensitive site (DHS) and its variations in domesticated allotetraploid cotton (Gossypium hirsutumandGossypium barbadense, AADD) and its extant AA (Gossypium arboreum) and DD (Gossypium raimondii) progenitors. We observed distinct DHS distributions betweenG. arboreumandG. raimondii. In contrast, the DHSs of the two subgenomes ofG. hirsutumandG. barbadenseshowed a convergent distribution. This convergent distribution of DHS was also present in the wild allotetraploidsGossypium darwiniiandG. hirsutumvar.yucatanense, but absent from a resynthesized hybrid ofG. arboreumandG. raimondii, suggesting that it may be a common feature in polyploids, and not a consequence of domestication after polyploidization. We revealed that putativecis-regulatory elements (CREs) derived from polyploidization-related DHSs were dominated by several families, including Dof, ERF48, and BPC1. Strikingly, 56.6% of polyploidization-related DHSs were derived from transposable elements (TEs). Moreover, we observed positive correlations between DHS accessibility and the histone marks H3K4me3, H3K27me3, H3K36me3, H3K27ac, and H3K9ac, indicating that coordinated interplay among histone modifications, TEs, and CREs drives the DHS landscape dynamics under polyploidization. Collectively, these findings advance our understanding of the regulatory architecture in plants and underscore the complexity of regulome evolution during polyploidization.
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- Award ID(s):
- 1658709
- PAR ID:
- 10567108
- Publisher / Repository:
- National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 119
- Issue:
- 44
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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