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Erysiphe necator is an economically important biotrophic fungal pathogen responsible for powdery mildew disease on grapevine. Currently, genome sequences are available for only a few E. necator isolates from the United States. Based on the combination of Nanopore and Illumina sequencing technologies, we present here the complete genome assembly for an isolate of E. necator, NAFU1, identified in China. We acquired a total of 15.93 Gb of raw reads. These reads were processed into a 61.12-Mb genome assembly containing 73 contigs with an N 50 of 2.06 Mb and a maximum length of 6.05 Mb. Combining the results of three gene-prediction modules (i.e., an evidence-based gene modeler [EVidenceModeler], an ab initio gene modeler, and a homology-based gene modeler), we predicted 7,235 protein-coding genes in the assembled genome of E. necator NAFU1. This information will facilitate studies of genome evolution and pathogenicity mechanisms of E. necator and other powdery mildew species through comparative genome sequence analysis and other molecular genetic tools. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
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A reference genome for the long-term kleptoplast-retaining sea slug Elysia crispata morphotype clarki
Abstract Several species of sacoglossan sea slugs possess the incredible ability to sequester chloroplasts from the algae they consume. These “photosynthetic animals” incorporate stolen chloroplasts, called kleptoplasts, into the epithelial cells of tubules that extend from their digestive tracts throughout their bodies. The mechanism by which these slugs maintain functioning kleptoplasts in the absence of an algal nuclear genome is unknown. Here, we report a draft genome of the sacoglossan slug Elysia crispata morphotype clarki, a morphotype native to the Florida Keys that can retain photosynthetically active kleptoplasts for several months without feeding. We used a combination of Oxford Nanopore Technologies long reads and Illumina short reads to produce a 786-Mb assembly (N50 = 0.459 Mb) containing 68,514 predicted protein-coding genes. A phylogenetic analysis found no evidence of horizontal acquisition of genes from algae. We performed gene family and gene expression analyses to identify E. crispata genes unique to kleptoplast-containing slugs that were more highly expressed in fed versus unfed developmental life stages. Consistent with analyses in other kleptoplastic slugs, our investigation suggests that genes encoding lectin carbohydrate-binding proteins and those involved in regulation of reactive oxygen species and immunity may play a role in kleptoplast retention. Lastly, we identified four polyketide synthase genes that could potentially encode proteins producing UV- and oxidation-blocking compounds in slug cell membranes. The genome of E. crispata is a quality resource that provides potential targets for functional analyses and enables further investigation into the evolution and mechanisms of kleptoplasty in animals.
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- Award ID(s):
- 1831493
- PAR ID:
- 10535970
- Editor(s):
- Mallarino, R
- Publisher / Repository:
- G3
- Date Published:
- Journal Name:
- G3: Genes, Genomes, Genetics
- Volume:
- 13
- Issue:
- 12
- ISSN:
- 2160-1836
- Format(s):
- Medium: X
- 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/10.1093/g3journal/jkad234
