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Honaas, L.

Publications and source records attributed to Honaas, L..

4 recordsLinked to original sources

A Phased, Chromosome-scale Genome for Malus domestica 'WA 38'

Genome sequencing for agriculturally important Rosaceous crops has made rapid progress both in completeness and annotation quality. Whole genome sequence and annotation gives breeders, researchers, and growers information about cultivar specific traits such as fruit quality, disease resistance, and informs strategies to enhance postharvest storage. Here we present a haplotype-phased, chromosomal level genome of Malus domestica, WA 38, a new apple cultivar released to market in 2017 as Cosmic Crisp (R). Using both short and long read sequencing data with a k-mer based approach, chromosomes originating from each parent were assembled and segregated. This is the first pome fruit genome fully phased into parental haplotypes in which chromosomes from each parent are identified and separated into their unique, respective haplomes. The two haplome assemblies, Honeycrisp originated HapA and Enterprise originated HapB, are about 650 Megabases each, and both have a BUSCO score of 98.7% complete. A total of 53,028 and 54,235 genes were annotated from HapA and HapB, respectively. Additionally, we provide genome-scale comparisons to Gala, Honeycrisp, and other relevant cultivars highlighting major differences in genome structure and gene family circumscription. This assembly and annotation was done in collaboration with the American Campus Tree Genomes project that includes WA 38 (Washington State University), dAnjou pear (Auburn University), and many more. To ensure transparency, reproducibility, and applicability for any genome project, our genome assembly and annotation workflow is recorded in detail and shared under a public GitLab repository. All software is containerized, offering a simple implementation of the workflow.

genomics↗

A chromosome-scale assembly for dAnjou pear

Cultivated pear consists of several Pyrus species with P. communis (European pear) representing a large fraction of worldwide production. As a relatively recently domesticated crop and perennial tree, pear can benefit from genome-assisted breeding. Additionally, comparative genomics within Rosaceae promises greater understanding of evolution within this economically important family. Here, we generate a fully-phased chromosome-scale genome assembly of P. communis cv. dAnjou. Using PacBio HiFi and Dovetail Omni-C reads, the genome is resolved into the expected 17 chromosomes, with each haplotype totalling nearly 540 Megabases and a contig N50 of nearly 14 Mb. Both haplotypes are highly syntenic to each other, and to the Malus domestica Honeycrisp apple genome. Nearly 45,000 genes were annotated in each haplotype, over 90% of which have direct RNA-seq expression evidence. We detect signatures of the known whole-genome duplication shared between apple and pear, and we estimate 57% of dAnjou genes are retained in duplicate derived from this event. This genome highlights the value of generating phased diploid assemblies for recovering the full allelic complement in highly heterozygous crop species.

genomics↗

PlantTribes2: tools for comparative gene family analysis in plant genomics

Plant genome-scale resources are being generated at an increasing rate as sequencing technologies continue to improve and raw data costs continue to fall; however, the cost of downstream analyses remains large. This has resulted in a considerable range of genome assembly and annotation qualities across plant genomes due to their varying sizes, complexity, and the technology used for the assembly and annotation. To effectively work across genomes, researchers increasingly rely on comparative genomic approaches that integrate across plant community resources and data types. Such efforts have aided the genome annotation process and yielded novel insights into the evolutionary history of genomes and gene families, including complex non-model organisms. The essential tools to achieve these insights rely on gene family analysis at a genome-scale, but they are not well integrated for rapid analysis of new data, and the learning curve can be steep. Here we present PlantTribes2, a scalable, easily accessible, highly customizable, and broadly applicable gene family analysis framework with multiple entry points including user provided data. It uses objective classifications of annotated protein sequences from existing, high-quality plant genomes for comparative and evolutionary studies. PlantTribes2 can improve transcript models and then sort them, either genome-scale annotations or individual gene coding sequences, into pre-computed orthologous gene family clusters with rich functional annotation information. Then, for gene families of interest, PlantTribes2 performs downstream analyses and customizable visualizations including, (1) multiple sequence alignment, (2) gene family phylogeny, (3) estimation of synonymous and non-synonymous substitution rates among homologous sequences, and (4) inference of large-scale duplication events. We give examples of PlantTribes2 applications in functional genomic studies of economically important plant families, namely transcriptomics in the weedy Orobanchaceae and a core orthogroup analysis (CROG) in Rosaceae. PlantTribes2 is freely available for use within the main public Galaxy instance and can be downloaded from GitHub or Bioconda. Importantly, PlantTribes2 can be readily adapted for use with genomic and transcriptomic data from any kind of organism.

bioinformatics↗

A phased, chromosome-scale genome of 'Honeycrisp' apple (Malus domestica)

Honeycrisp is one of the most valuable apple cultivars grown in the United States and a popular breeding parent due to its superior fruit quality traits, high levels of cold hardiness, and disease resistance. However, it suffers from a number of physiological disorders and is susceptible to production and postharvest issues. Although several apple genomes have been sequenced in the last decade, there is still a substantial knowledge gap in understanding the genetic mechanisms underlying cultivar-specific traits. Here we present a fully phased, chromosome-level genome of Honeycrisp apples, using PacBio HiFi, Omni-C, and Illumina sequencing platforms. Our genome assembly is by far the most contiguous among all the apple genomes. The sizes of the two assembled haplomes are 674 Mb and 660 Mb, with contig N50s of 32.8 Mb and 31.6 Mb, respectively. In total, 47,563 and 48,655 protein coding genes were annotated from each haplome, capturing 96.8-97.4% complete BUSCOs in the eudicot database, the most complete among all Malus annotations. A gene family analysis using seven Malus genomes shows that a vast majority of Honeycrisp genes are assigned into orthogroups shared with other genomes, but it also reveals 121 Honeycrisp-specific orthogroups. We provide a valuable resource for understanding the genetic basis of horticulturally important traits in apples and other related tree fruit species, including at-harvest and postharvest fruit quality, abiotic stress tolerance, and disease resistance, all of which can enhance breeding efforts in Rosaceae.

genomics↗