Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes

Spruces (Picea spp.) are coniferous trees widespread in boreal and mountainous forests of the northern hemisphere, with large economic significance and enormous contributions to global carbon sequestration. Spruces harbor very large genomes with high repetitiveness, hampering their comparative analy...

Full description

Bibliographic Details
Main Authors: Gagalova, Kristina K., Warren, R.L., Coombe, L., Wong, J., Nip, K.M., Yuen, M.M.S., Whitehill, J.G.A., Celedon, J.M., Ritland, C., Taylor, G.A., Cheng, D., Plettner, P., Hammond, S.A., Mohamadi, H., Zhao, Y., Moore, R.A., Mungall, A.J., Boyle, B., Laroche, J., Cottrell, J., Mackay, J.J., Lamothe, M., Gérardi, S., Isabel, N., Pavy, N., Jones, S.J.M., Bohlmann, J., Bousquet, J., Birol, I.
Format: Journal Article
Language:English
Published: 2022
Subjects:
Online Access:http://hdl.handle.net/20.500.11937/96868
_version_ 1848766201808814080
author Gagalova, Kristina K.
Warren, R.L.
Coombe, L.
Wong, J.
Nip, K.M.
Yuen, M.M.S.
Whitehill, J.G.A.
Celedon, J.M.
Ritland, C.
Taylor, G.A.
Cheng, D.
Plettner, P.
Hammond, S.A.
Mohamadi, H.
Zhao, Y.
Moore, R.A.
Mungall, A.J.
Boyle, B.
Laroche, J.
Cottrell, J.
Mackay, J.J.
Lamothe, M.
Gérardi, S.
Isabel, N.
Pavy, N.
Jones, S.J.M.
Bohlmann, J.
Bousquet, J.
Birol, I.
author_facet Gagalova, Kristina K.
Warren, R.L.
Coombe, L.
Wong, J.
Nip, K.M.
Yuen, M.M.S.
Whitehill, J.G.A.
Celedon, J.M.
Ritland, C.
Taylor, G.A.
Cheng, D.
Plettner, P.
Hammond, S.A.
Mohamadi, H.
Zhao, Y.
Moore, R.A.
Mungall, A.J.
Boyle, B.
Laroche, J.
Cottrell, J.
Mackay, J.J.
Lamothe, M.
Gérardi, S.
Isabel, N.
Pavy, N.
Jones, S.J.M.
Bohlmann, J.
Bousquet, J.
Birol, I.
author_sort Gagalova, Kristina K.
building Curtin Institutional Repository
collection Online Access
description Spruces (Picea spp.) are coniferous trees widespread in boreal and mountainous forests of the northern hemisphere, with large economic significance and enormous contributions to global carbon sequestration. Spruces harbor very large genomes with high repetitiveness, hampering their comparative analysis. Here, we present and compare the genomes of four different North American spruces: the genome assemblies for Engelmann spruce (Picea engelmannii) and Sitka spruce (Picea sitchensis) together with improved and more contiguous genome assemblies for white spruce (Picea glauca) and for a naturally occurring introgress of these three species known as interior spruce (P. engelmannii × glauca × sitchensis). The genomes were structurally similar, and a large part of scaffolds could be anchored to a genetic map. The composition of the interior spruce genome indicated asymmetric contributions from the three ancestral genomes. Phylogenetic analysis of the nuclear and organelle genomes revealed a topology indicative of ancient reticulation. Different patterns of expansion of gene families among genomes were observed and related with presumed diversifying ecological adaptations. We identified rapidly evolving genes that harbored high rates of non-synonymous polymorphisms relative to synonymous ones, indicative of positive selection and its hitchhiking effects. These gene sets were mostly distinct between the genomes of ecologically contrasted species, and signatures of convergent balancing selection were detected. Stress and stimulus response was identified as the most frequent function assigned to expanding gene families and rapidly evolving genes. These two aspects of genomic evolution were complementary in their contribution to divergent evolution of presumed adaptive nature. These more contiguous spruce giga-genome sequences should strengthen our understanding of conifer genome structure and evolution, as their comparison offers clues into the genetic basis of adaptation and ecology of conifers at the genomic level. They will also provide tools to better monitor natural genetic diversity and improve the management of conifer forests. The genomes of four closely related North American spruces indicate that their high similarity at the morphological level is paralleled by the high conservation of their physical genome structure. Yet, the evidence of divergent evolution is apparent in their rapidly evolving genomes, supported by differential expansion of key gene families and large sets of genes under positive selection, largely in relation to stimulus and environmental stress response.
first_indexed 2025-11-14T11:47:23Z
format Journal Article
id curtin-20.500.11937-96868
institution Curtin University Malaysia
institution_category Local University
language eng
last_indexed 2025-11-14T11:47:23Z
publishDate 2022
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-968682025-02-11T04:20:36Z Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes Gagalova, Kristina K. Warren, R.L. Coombe, L. Wong, J. Nip, K.M. Yuen, M.M.S. Whitehill, J.G.A. Celedon, J.M. Ritland, C. Taylor, G.A. Cheng, D. Plettner, P. Hammond, S.A. Mohamadi, H. Zhao, Y. Moore, R.A. Mungall, A.J. Boyle, B. Laroche, J. Cottrell, J. Mackay, J.J. Lamothe, M. Gérardi, S. Isabel, N. Pavy, N. Jones, S.J.M. Bohlmann, J. Bousquet, J. Birol, I. Picea species conifers divergent adaptive evolution genetic map genome sequence non-synonymous SNPs phylogeny positive selection super-scaffolds Expressed Sequence Tags Genome, Plant Multigene Family Phylogeny Picea Tracheophyta Picea Phylogeny Genome, Plant Multigene Family Expressed Sequence Tags Tracheophyta Spruces (Picea spp.) are coniferous trees widespread in boreal and mountainous forests of the northern hemisphere, with large economic significance and enormous contributions to global carbon sequestration. Spruces harbor very large genomes with high repetitiveness, hampering their comparative analysis. Here, we present and compare the genomes of four different North American spruces: the genome assemblies for Engelmann spruce (Picea engelmannii) and Sitka spruce (Picea sitchensis) together with improved and more contiguous genome assemblies for white spruce (Picea glauca) and for a naturally occurring introgress of these three species known as interior spruce (P. engelmannii × glauca × sitchensis). The genomes were structurally similar, and a large part of scaffolds could be anchored to a genetic map. The composition of the interior spruce genome indicated asymmetric contributions from the three ancestral genomes. Phylogenetic analysis of the nuclear and organelle genomes revealed a topology indicative of ancient reticulation. Different patterns of expansion of gene families among genomes were observed and related with presumed diversifying ecological adaptations. We identified rapidly evolving genes that harbored high rates of non-synonymous polymorphisms relative to synonymous ones, indicative of positive selection and its hitchhiking effects. These gene sets were mostly distinct between the genomes of ecologically contrasted species, and signatures of convergent balancing selection were detected. Stress and stimulus response was identified as the most frequent function assigned to expanding gene families and rapidly evolving genes. These two aspects of genomic evolution were complementary in their contribution to divergent evolution of presumed adaptive nature. These more contiguous spruce giga-genome sequences should strengthen our understanding of conifer genome structure and evolution, as their comparison offers clues into the genetic basis of adaptation and ecology of conifers at the genomic level. They will also provide tools to better monitor natural genetic diversity and improve the management of conifer forests. The genomes of four closely related North American spruces indicate that their high similarity at the morphological level is paralleled by the high conservation of their physical genome structure. Yet, the evidence of divergent evolution is apparent in their rapidly evolving genomes, supported by differential expansion of key gene families and large sets of genes under positive selection, largely in relation to stimulus and environmental stress response. 2022 Journal Article http://hdl.handle.net/20.500.11937/96868 10.1111/tpj.15889 eng http://creativecommons.org/licenses/by/4.0/ fulltext
spellingShingle Picea species
conifers
divergent adaptive evolution
genetic map
genome sequence
non-synonymous SNPs
phylogeny
positive selection
super-scaffolds
Expressed Sequence Tags
Genome, Plant
Multigene Family
Phylogeny
Picea
Tracheophyta
Picea
Phylogeny
Genome, Plant
Multigene Family
Expressed Sequence Tags
Tracheophyta
Gagalova, Kristina K.
Warren, R.L.
Coombe, L.
Wong, J.
Nip, K.M.
Yuen, M.M.S.
Whitehill, J.G.A.
Celedon, J.M.
Ritland, C.
Taylor, G.A.
Cheng, D.
Plettner, P.
Hammond, S.A.
Mohamadi, H.
Zhao, Y.
Moore, R.A.
Mungall, A.J.
Boyle, B.
Laroche, J.
Cottrell, J.
Mackay, J.J.
Lamothe, M.
Gérardi, S.
Isabel, N.
Pavy, N.
Jones, S.J.M.
Bohlmann, J.
Bousquet, J.
Birol, I.
Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title_full Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title_fullStr Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title_full_unstemmed Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title_short Spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
title_sort spruce giga-genomes: structurally similar yet distinctive with differentially expanding gene families and rapidly evolving genes
topic Picea species
conifers
divergent adaptive evolution
genetic map
genome sequence
non-synonymous SNPs
phylogeny
positive selection
super-scaffolds
Expressed Sequence Tags
Genome, Plant
Multigene Family
Phylogeny
Picea
Tracheophyta
Picea
Phylogeny
Genome, Plant
Multigene Family
Expressed Sequence Tags
Tracheophyta
url http://hdl.handle.net/20.500.11937/96868