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Abstract Dragon fruits are tropical fruits economically important for agricultural industries. As members of the family ofCactaceae, they have evolved to adapt to the arid environment. Here we report the draft genome ofHylocereus undatus, commercially known as the white-fleshed dragon fruit. The chromosomal level genome assembly contains 11 longest scaffolds corresponding to the 11 chromosomes ofH. undatus. Genome annotation ofH. undatusfound ~29,000 protein-coding genes, similar toCarnegiea gigantea(saguaro). Whole-genome duplication (WGD) analysis revealed a WGD event in the last common ancestor ofCactaceaefollowed by extensive genome rearrangements. The divergence time betweenH. undatusandC. giganteawas estimated to be 9.18 MYA. Functional enrichment analysis of orthologous gene clusters (OGCs) in sixCactaceaeplants found significantly enriched OGCs in drought resistance. Fruit flavor-related functions were overrepresented in OGCs that are significantly expanded inH. undatus. TheH. undatusdraft genome also enabled the discovery of carbohydrate and plant cell wall-related functional enrichment in dragon fruits treated with trypsin for a longer storage time. Lastly, genes of the betacyanin (a red-violet pigment and antioxidant with a very high concentration in dragon fruits) biosynthetic pathway were found to be co-localized on a 12 Mb region of one chromosome. The consequence may be a higher efficiency of betacyanin biosynthesis, which will need experimental validation in the future. TheH. undatusdraft genome will be a great resource to study various cactus plants.
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Building a eukaryotic chromosome arm by de novo design and synthesis
Abstract The genome of an organism is inherited from its ancestor and continues to evolve over time, however, the extent to which the current version could be altered remains unknown. To probe the genome plasticity ofSaccharomyces cerevisiae, here we replace the native left arm of chromosome XII (chrXIIL) with a linear artificial chromosome harboring small sets of reconstructed genes. We find that as few as 12 genes are sufficient for cell viability, whereas 25 genes are required to recover the partial fitness defects observed in the 12-gene strain. Next, we demonstrate that these genes can be reconstructed individually using synthetic regulatory sequences and recoded open-reading frames with a “one-amino-acid-one-codon” strategy to remain functional. Finally, a synthetic neochromsome with the reconstructed genes is assembled which could substitutechrXIILfor viability. Together, our work not only highlights the high plasticity of yeast genome, but also illustrates the possibility of making functional eukaryotic chromosomes from entirely artificial sequences.
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- PAR ID:
- 10651631
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Communications
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-023-43531-5
