Mechanisms of Functional and Physical Genome Reduction in Photosynthetic and Nonphotosynthetic Parasitic Plants of the Broomrape Family
Susann Wicke,Kai F. Müller,Claude W. de Pamphilis,Dietmar Quandt,Norman J. Wickett,Yan Zhang,Susanne S. Renner,Gerald M. Schneeweiss +7 more
TLDR
The authors report the complete plastomes of 10 photosynthetic and nonphotosynthetic parasites plus their nonparasitic sister from the broomrape family (Orobanchaceae), finding that the establishment of obligate parasitism triggers the relaxation of selective constraints.Abstract:
Nonphotosynthetic plants possess strongly reconfigured plastomes attributable to convergent losses of photosynthesis and housekeeping genes, making them excellent systems for studying genome evolution under relaxed selective pressures. We report the complete plastomes of 10 photosynthetic and nonphotosynthetic parasites plus their nonparasitic sister from the broomrape family (Orobanchaceae). By reconstructing the history of gene losses and genome reconfigurations, we find that the establishment of obligate parasitism triggers the relaxation of selective constraints. Partly because of independent losses of one inverted repeat region, Orobanchaceae plastomes vary 3.5-fold in size, with 45 kb in American squawroot (Conopholis americana) representing the smallest plastome reported from land plants. Of the 42 to 74 retained unique genes, only 16 protein genes, 15 tRNAs, and four rRNAs are commonly found. Several holoparasites retain ATP synthase genes with intact open reading frames, suggesting a prolonged function in these plants. The loss of photosynthesis alters the chromosomal architecture in that recombinogenic factors accumulate, fostering large-scale chromosomal rearrangements as functional reduction proceeds. The retention of DNA fragments is strongly influenced by both their proximity to genes under selection and the co-occurrence with those in operons, indicating complex constraints beyond gene function that determine the evolutionary survival time of plastid regions in nonphotosynthetic plants.read more
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References
More filters
Journal ArticleDOI
MODELTEST: testing the model of DNA substitution.
David Posada,Keith A. Crandall +1 more
TL;DR: The program MODELTEST uses log likelihood scores to establish the model of DNA evolution that best fits the data.
Journal ArticleDOI
progressiveMauve: Multiple Genome Alignment with Gene Gain, Loss and Rearrangement
TL;DR: A new method to align two or more genomes that have undergone rearrangements due to recombination and substantial amounts of segmental gain and loss is described, demonstrating high accuracy in situations where genomes have undergone biologically feasible amounts of genome rearrangement, segmental loss and loss.
Journal ArticleDOI
Automatic annotation of organellar genomes with DOGMA
TL;DR: The Dual Organellar GenoMe Annotator (DOGMA) automates the annotation of organellar genomes and allows the use of BLAST searches against a custom database, and conservation of basepairing in the secondary structure of animal mitochondrial tRNAs to identify and annotate genes.
Journal ArticleDOI
The complete nucleotide sequence of the tobacco chloroplast genome: its gene organization and expression.
Kazuo Shinozaki,Masaru Ohme,Minoru Tanaka,Tatsuya Wakasugi,Nobuaki Hayashida,Tohru Matsubayashi,N. Zaita,J. Chunwongse,Junichi Obokata,Kazuko Yamaguchi-Shinozaki,Chikara Ohto,Keita Torazawa,B. Y. Meng,Mamoru Sugita,Hiroshi Deno,T. Kamogashira,Kyoji Yamada,Jun Kusuda,F. Takaiwa,Akira Kato,N. Tohdoh,Hiroaki Shimada,Masahiro Sugiura +22 more
TL;DR: Five sequences coding for proteins homologous to components of the respiratory‐chain NADH dehydrogenase from human mitochondria have been found and sequence and expression analyses indicate both prokaryotic and eukaryotic features of the chloroplast genes.
Journal ArticleDOI
Detecting Correlated Evolution on Phylogenies: A General Method for the Comparative Analysis of Discrete Characters
TL;DR: A new statistical method is presented for analysing the relationship between two discrete characters that are measured across a group of hierarchically evolved species or populations and assessing whether a pattern of association across the group is evidence for correlated evolutionary change in the two characters.