Abstract Comparisons of high-quality, reference butterfly, and moth genomes have been instrumental to advancing our understanding of how hybridization, and natural selection drive genomic change during the origin of new species and novel traits. Here, we present a genome assembly of the Southern Dogface butterfly, Zerene cesonia (Pieridae) whose brilliant wing colorations have been implicated in developmental plasticity, hybridization, sexual selection, and speciation. We assembled 266,407,278 bp of the Z. cesonia genome, which accounts for 98.3% of the estimated 271 Mb genome size. Using a hybrid approach involving Chicago libraries with Hi-Rise assembly and a diploid Meraculous assembly, the final haploid genome was assembled. In the final assembly, nearly all autosomes and the Z chromosome were assembled into single scaffolds. The largest 29 scaffolds accounted for 91.4% of the genome assembly, with the remaining ∼8% distributed among another 247 scaffolds and overall N50 of 9.2 Mb. Tissue-specific RNA-seq informed annotations identified 16,442 protein-coding genes, which included 93.2% of the arthropod Benchmarking Universal Single-Copy Orthologs (BUSCO). The Z. cesonia genome assembly had ∼9% identified as repetitive elements, with a transposable element landscape rich in helitrons. Similar to other Lepidoptera genomes, Z. cesonia showed a high conservation of chromosomal synteny. The Z. cesonia assembly provides a high-quality reference formore »
A High-Quality Reference Genome Assembly of the Saltwater Crocodile, Crocodylus porosus, Reveals Patterns of Selection in Crocodylidae
Abstract Crocodilians are an economically, culturally, and biologically important group. To improve researchers’ ability to study genome structure, evolution, and gene regulation in the clade, we generated a high-quality de novo genome assembly of the saltwater crocodile, Crocodylus porosus, from Illumina short read data from genomic libraries and in vitro proximity-ligation libraries. The assembled genome is 2,123.5 Mb, with N50 scaffold size of 17.7 Mb and N90 scaffold size of 3.8 Mb. We then annotated this new assembly, increasing the number of annotated genes by 74%. In total, 96% of 23,242 annotated genes were associated with a functional protein domain. Furthermore, multiple noncoding functional regions and mappable genetic markers were identified. Upon analysis and overlapping the results of branch length estimation and site selection tests for detecting potential selection, we found 16 putative genes under positive selection in crocodilians, 10 in C. porosus and 6 in Alligator mississippiensis. The annotated C. porosus genome will serve as an important platform for osmoregulatory, physiological, and sex determination studies, as well as an important reference in investigating the phylogenetic relationships of crocodilians, birds, and other tetrapods.
- Editors:
- Cordaux, Richard
- Award ID(s):
- 1838283
- Publication Date:
- NSF-PAR ID:
- 10321668
- Journal Name:
- Genome Biology and Evolution
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 1759-6653
- Sponsoring Org:
- National Science Foundation
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- https://doi.org/10.1093/gbe/evz269
