Bread wheat (Triticum aestivum) is a major food crop and an important plant system for agricultural genetics research. However, due to the complexity and size of its allohexaploid genome, genomic resources are limited compared to other major crops. The IWGSC recently published a reference genome and associated annotation (IWGSC CS v1.0, Chinese Spring) that has been widely adopted and utilized by the wheat community. Although this reference assembly represents all three wheat subgenomes at chromosome-scale, it was derived from short reads, and thus is missing a substantial portion of the expected 16 Gbp of genomic sequence. We earlier published an independent wheat assembly (Triticum_aestivum_3.1, Chinese Spring) that came much closer in length to the expected genome size, although it was only a contig-level assembly lacking gene annotations. Here, we describe a reference-guided effort to scaffold those contigs into chromosome-length pseudomolecules, add in any missing sequence that was unique to the IWGSC CS v1.0 assembly, and annotate the resulting pseudomolecules with genes. Our updated assembly, Triticum_aestivum_4.0, contains 15.07 Gbp of non-gap sequence anchored to chromosomes, which is 1.2 Gbps more than the previous reference assembly. It includes 108,639 genes unambiguously localized to chromosomes, including over 2,000 genes that were previously unplaced.more »
The genome of the American groundhog, Marmota monax
We sequenced the genome of the North American groundhog, Marmota monax , also known as the woodchuck. Our sequencing strategy included a combination of short, high-quality Illumina reads plus long reads generated by both Pacific Biosciences and Oxford Nanopore instruments. Assembly of the combined data produced a genome of 2.74 Gbp in total length, with an N50 contig size of 1,094,236 bp. To annotate the genome, we mapped the genes from another M. monax genome and from the closely related Alpine marmot, Marmota marmota , onto our assembly, resulting in 20,559 annotated protein-coding genes and 28,135 transcripts. The genome assembly and annotation are available in GenBank under BioProject PRJNA587092 .
- Award ID(s):
- 1744309
- Publication Date:
- NSF-PAR ID:
- 10308626
- Journal Name:
- F1000Research
- Volume:
- 9
- ISSN:
- 2046-1402
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.12688/f1000research.25970.1
