edoc

Evolution of a morphological novelty occurred before genome compaction in a lineage of extreme parasites

Haag, K. L. and James, T. Y. and Pombert, J. F. and Larsson, R. and Schaer, T. M. M. and Refardt, D. and Ebert, D.. (2014) Evolution of a morphological novelty occurred before genome compaction in a lineage of extreme parasites. Proceedings of the National Academy of Sciences of the United States of America, Vol. 111, no. 43. pp. 15480-15485.

[img] PDF - Accepted Version
Restricted to Repository staff only

1017Kb

Official URL: http://edoc.unibas.ch/dok/A6337821

Downloads: Statistics Overview

Abstract

Intracellular parasitism results in extreme adaptations, whose evolutionary history is difficult to understand, because the parasites and their known free-living relatives are so divergent from one another. Microsporidia are intracellular parasites of humans and other animals, which evolved highly specialized morphological structures, but also extreme physiologic and genomic simplification. They are suggested to be an early-diverging branch on the fungal tree, but comparisons to other species are difficult because their rates of molecular evolution are exceptionally high. Mitochondria in microsporidia have degenerated into organelles called mitosomes, which have lost a genome and the ability to produce ATP. Here we describe a gut parasite of the crustacean Daphnia that despite having remarkable morphological similarity to the microsporidia, has retained genomic features of its fungal ancestors. This parasite, which we name Mitosporidium daphniae gen. et sp. nov., possesses a mitochondrial genome including genes for oxidative phosphorylation, yet a spore stage with a highly specialized infection apparatus-the polar tube-uniquely known only from microsporidia. Phylogenomics places M. daphniae at the root of the microsporidia. A comparative genomic analysis suggests that the reduction in energy metabolism, a prominent feature of microsporidian evolution, was preceded by a reduction in the machinery controlling cell cycle, DNA recombination, repair, and gene expression. These data show that the morphological features unique to M. daphniae and other microsporidia were already present before the lineage evolved the extreme host metabolic dependence and loss of mitochondrial respiration for which microsporidia are well known.
Faculties and Departments:05 Faculty of Science > Departement Umweltwissenschaften > Zoologie > Evolutionary Biology (Ebert)
UniBasel Contributors:Ebert, Dieter and Haag, Karen and Schär, Tobias
Item Type:Article, refereed
Article Subtype:Research Article
Bibsysno:Link to catalogue
ISSN:0027-8424
Note:Publication type according to Uni Basel Research Database: Journal article
Language:English
Related URLs:
Identification Number:
Last Modified:31 Dec 2015 10:56
Deposited On:06 Feb 2015 09:59

Repository Staff Only: item control page