Matthew G. Johnson

Dr. Matthew G. Johnson

orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
12 July 2016 in Applications in Plant Sciences
Verified
Journal Article
Open access
PDF file
MJMatthew G. Johnson
Matthew G. Johnson
EGElliot M. Gardner
Elliot M. Gardner
Yang LiuYang Liu
Yang Liu
RMRafael Medina
Rafael Medina
BGBernard Goffinet
Bernard Goffinet
NWNorman J. Wickett
Norman J. Wickett
Premise of the study: Using sequence data generated via target enrichment for phylogenetics requires reassembly of high‐throughput sequence reads into loci, presenting a number of bioinformatics challenges. We developed HybPiper as a user‐friendly platform for assembly of gene regions, extraction of exon and intron sequences, and identification of paralogous gene copies. We test HybPiper using baits designed to target 333 phylogenetic markers and 125 genes of functional significance in Artocarpus (Moraceae).Methods and Results: HybPiper implements parallel execution of sequence assembly in three phases: read mapping, contig assembly, and target sequence extraction. The pipeline was able to recover nearly complete gene sequences for all genes in 22 species of Artocarpus. HybPiper also recovered more than 500 bp of nontargeted intron sequence in over half of the phylogenetic markers and identified paralogous gene copies in Artocarpus.Conclusions: HybPiper was designed for Linux and Mac OS X and is freely available at https://github.com/mossmatters/HybPiper.

10 December 2018 in Systematic Biology
Verified
Journal Article
Open access
MJMatthew G. Johnson
Matthew G. Johnson
LPLisa Pokorny
Lisa Pokorny
SDSteven Dodsworth
Steven Dodsworth
LBLaura R Botigué
Laura R Botigué
RCRobyn S Cowan
Robyn S Cowan
NWNorman J Wickett
Norman J Wickett
Sequencing of target-enriched libraries is an efficient and cost-effective method for obtaining DNA sequence data from hundreds of nuclear loci for phylogeny reconstruction. Much of the cost of developing targeted sequencing approaches is associated with the generation of preliminary data needed for the identification of orthologous loci for probe design. In plants, identifying orthologous loci has proven difficult due to a large number of whole-genome duplication events, especially in the angiosperms (flowering plants). We used multiple sequence alignments from over 600 angiosperms for 353 putatively single-copy protein-coding genes identified by the One Thousand Plant Transcriptomes Initiative to design a set of targeted sequencing probes for phylogenetic studies of any angiosperm group. To maximize the phylogenetic potential of the probes, while minimizing the cost of production, we introduce a k-medoids clustering approach to identify the minimum number of sequences necessary to represent each coding sequence in the final probe set. Using this method, 5-15 representative sequences were selected per orthologous locus, representing the sequence diversity of angiosperms more efficiently than if probes were designed using available sequenced genomes alone. To test our approximately 80,000 probes, we hybridized libraries from 42 species spanning all higher-order groups of angiosperms, with a focus on taxa not present in the sequence alignments used to design the probes. Out of a possible 353 coding sequences, we recovered an average of 283 per species and at least 100 in all species. Differences among taxa in sequence recovery could not be explained by relatedness to the representative taxa selected for probe design, suggesting that there is no phylogenetic bias in the probe set. Our probe set, which targeted 260 kbp of coding sequence, achieved a median recovery of 137 kbp per taxon in coding regions, a maximum recovery of 250 kbp, and an additional median of 212 kbp per taxon in flanking non-coding regions across all species. These results suggest that the Angiosperms353 probe set described here is effective for any group of flowering plants and would be useful for phylogenetic studies from the species level to higher-order groups, including the entire angiosperm clade itself.

24 April 2024 in Nature
Verified
Journal Article
Open access
PDF file
AZAlexandre R. Zuntini
Alexandre R. Zuntini
TCTom Carruthers
Tom Carruthers
OMOlivier Maurin
Olivier Maurin
PBPaul C. Bailey
Paul C. Bailey
KLKevin Leempoel
Kevin Leempoel
WBWilliam J. Baker
William J. Baker
Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods1,2. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome3,4. Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins5–7. However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes8. This 15-fold increase in genus-level sampling relative to comparable nuclear studies9 provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating many previously predicted relationships. Scaling this tree to time using 200 fossils, we discovered that early angiosperm evolution was characterized by high gene tree conflict and explosive diversification, giving rise to more than 80% of extant angiosperm orders. Steady diversification ensued through the remaining Mesozoic Era until rates resurged in the Cenozoic Era, concurrent with decreasing global temperatures and tightly linked with gene tree conflict. Taken together, our extensive sampling combined with advanced phylogenomic methods shows the deep history and full complexity in the evolution of a megadiverse clade.

1 March 2018 in Applications in Plant Sciences
Verified
Journal Article
Open access
PDF file
MMMichael R. McKain
Michael R. McKain
MJMatthew G. Johnson
Matthew G. Johnson
SUSimon Uribe‐Convers
Simon Uribe‐Convers
DEDeren Eaton
Deren Eaton
YYYa Yang
Ya Yang
The past decade has seen a major breakthrough in our ability to easily and inexpensively sequence genome‐scale data from diverse lineages. The development of high‐throughput sequencing and long‐read technologies has ushered in the era of phylogenomics, where hundreds to thousands of nuclear genes and whole organellar genomes are routinely used to reconstruct evolutionary relationships. As a result, understanding which options are best suited for a particular set of questions can be difficult, especially for those just starting in the field. Here, we review the most recent advances in plant phylogenomic methods and make recommendations for project‐dependent best practices and considerations. We focus on the costs and benefits of different approaches in regard to the information they provide researchers and the questions they can address. We also highlight unique challenges and opportunities in plant systems, such as polyploidy, reticulate evolution, and the use of herbarium materials, identifying optimal methodologies for each. Finally, we draw attention to lingering challenges in the field of plant phylogenomics, such as reusability of data sets, and look at some up‐and‐coming technologies that may help propel the field even further.

2 April 2019 in Nature Communications
Verified
Journal Article
Open access
PDF file
YLYang Liu
Yang Liu
MJMatthew G. Johnson
Matthew G. Johnson
CCCymon J. Cox
Cymon J. Cox
RMRafael Medina
Rafael Medina
NDNicolas Devos
Nicolas Devos
BGBernard Goffinet
Bernard Goffinet
Mosses are a highly diverse lineage of land plants, whose diversification, spanning at least 400 million years, remains phylogenetically ambiguous due to the lack of fossils, massive early extinctions, late radiations, limited morphological variation, and conflicting signal among previously used markers. Here, we present phylogenetic reconstructions based on complete organellar exomes and a comparable set of nuclear genes for this major lineage of land plants. Our analysis of 142 species representing 29 of the 30 moss orders reveals that relative average rates of non-synonymous substitutions in nuclear versus plastid genes are much higher in mosses than in seed plants, consistent with the emerging concept of evolutionary dynamism in mosses. Our results highlight the evolutionary significance of taxa with reduced morphologies, shed light on the relative tempo and mechanisms underlying major cladogenic events, and suggest hypotheses for the relationships and delineation of moss orders.

17 July 2018 in New Phytologist
Verified
Journal Article
Open access
PDF file
TVTamara Villaverde
Tamara Villaverde
LPLisa Pokorny
Lisa Pokorny
SOSanna Olsson
Sanna Olsson
MRMario Rincón‐Barrado
Mario Rincón‐Barrado
MJMatthew G. Johnson
Matthew G. Johnson
ISIsabel Sanmartín
Isabel Sanmartín
Summary: Reconstructing phylogenetic relationships at the micro‐ and macroevoutionary levels within the same tree is problematic because of the need to use different data types and analytical frameworks. We test the power of target enrichment to provide phylogenetic resolution based on DNA sequences from above species to within populations, using a large herbarium sampling and Euphorbia balsamifera (Euphorbiaceae) as a case study. Target enrichment with custom probes was combined with genome skimming (Hyb‐Seq) to sequence 431 low‐copy nuclear genes and partial plastome DNA. We used supermatrix, multispecies‐coalescent approaches, and Bayesian dating to estimate phylogenetic relationships and divergence times. Euphorbia balsamifera, with a disjunct Rand Flora‐type distribution at opposite sides of Africa, comprises three well‐supported subspecies: western Sahelian sepium is sister to eastern African‐southern Arabian adenensis and Macaronesian‐southwest Moroccan balsamifera. Lineage divergence times support Late Miocene to Pleistocene diversification and climate‐driven vicariance to explain the Rand Flora pattern. We show that probes designed using genomic resources from taxa not directly related to the focal group are effective in providing phylogenetic resolution at deep and shallow evolutionary levels. Low capture efficiency in herbarium samples increased the proportion of missing data but did not bias estimation of phylogenetic relationships or branch lengths.