Dataset Information

Plant mating system transitions drive the macroevolution of defense strategies.

ABSTRACT: Understanding the factors that shape macroevolutionary patterns in functional traits is a central goal of evolutionary biology. Alternative strategies of sexual reproduction (inbreeding vs. outcrossing) have divergent effects on population genetic structure and could thereby broadly influence trait evolution. However, the broader evolutionary consequences of mating system transitions remain poorly understood, with the exception of traits related to reproduction itself (e.g., pollination). Across a phylogeny of 56 wild species of Solanaceae (nightshades), we show here that the repeated, unidirectional transition from ancestral self-incompatibility (obligate outcrossing) to self-compatibility (increased inbreeding) leads to the evolution of an inducible (vs. constitutive) strategy of plant resistance to herbivores. We demonstrate that inducible and constitutive defense strategies represent evolutionary alternatives and that the magnitude of the resulting macroevolutionary tradeoff is dependent on the mating system. Loss of self-incompatibility is also associated with the evolution of increased specificity in induced plant resistance. We conclude that the evolution of sexual reproductive variation may have profound effects on plant-herbivore interactions, suggesting a new hypothesis for the evolution of two primary strategies of plant defense.

SUBMITTER: Campbell SA

PROVIDER: S-EPMC3593862 | biostudies-other | 2013 Mar

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Plant mating system transitions drive the macroevolution of defense strategies.

Campbell Stuart A SA Kessler André A

Proceedings of the National Academy of Sciences of the United States of America 20130219 10

Understanding the factors that shape macroevolutionary patterns in functional traits is a central goal of evolutionary biology. Alternative strategies of sexual reproduction (inbreeding vs. outcrossing) have divergent effects on population genetic structure and could thereby broadly influence trait evolution. However, the broader evolutionary consequences of mating system transitions remain poorly understood, with the exception of traits related to reproduction itself (e.g., pollination). Across ...[more]

PMID: 23431190

Similar Datasets

Project description:Species within the human pathogenic Cryptococcus species complex are major threats to public health, causing approximately 1 million annual infections globally. Cryptococcus amylolentus is the most closely known related species of the pathogenic Cryptococcus species complex, and it is non-pathogenic. Additionally, while pathogenic Cryptococcus species have bipolar mating systems with a single large mating type (MAT) locus that represents a derived state in Basidiomycetes, C. amylolentus has a tetrapolar mating system with 2 MAT loci (P/R and HD) located on different chromosomes. Thus, studying C. amylolentus will shed light on the transition from tetrapolar to bipolar mating systems in the pathogenic Cryptococcus species, as well as its possible link with the origin and evolution of pathogenesis. In this study, we sequenced, assembled, and annotated the genomes of 2 C. amylolentus isolates, CBS6039 and CBS6273, which are sexual and interfertile. Genome comparison between the 2 C. amylolentus isolates identified the boundaries and the complete gene contents of the P/R and HD MAT loci. Bioinformatic and chromatin immunoprecipitation sequencing (ChIP-seq) analyses revealed that, similar to those of the pathogenic Cryptococcus species, C. amylolentus has regional centromeres (CENs) that are enriched with species-specific transposable and repetitive DNA elements. Additionally, we found that while neither the P/R nor the HD locus is physically closely linked to its centromere in C. amylolentus, and the regions between the MAT loci and their respective centromeres show overall synteny between the 2 genomes, both MAT loci exhibit genetic linkage to their respective centromere during meiosis, suggesting the presence of recombinational suppressors and/or epistatic gene interactions in the MAT-CEN intervening regions. Furthermore, genomic comparisons between C. amylolentus and related pathogenic Cryptococcus species provide evidence that multiple chromosomal rearrangements mediated by intercentromeric recombination have occurred during descent of the 2 lineages from their common ancestor. Taken together, our findings support a model in which the evolution of the bipolar mating system was initiated by an ectopic recombination event mediated by similar repetitive centromeric DNA elements shared between chromosomes. This translocation brought the P/R and HD loci onto the same chromosome, and further chromosomal rearrangements then resulted in the 2 MAT loci becoming physically linked and eventually fusing to form the single contiguous MAT locus that is now extant in the pathogenic Cryptococcus species.

Dataset Information

Plant mating system transitions drive the macroevolution of defense strategies.

Publications

Plant mating system transitions drive the macroevolution of defense strategies.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets