Characterisation and evolution of chromosome complements of carnivorous Lentibulariaceae
Final Report Abstract
The carnivorous genus Genlisea comprises species with the hitherto smallest angiosperm genomes and displays a ~25-fold infrageneric genome size variation. For a species with a very small genome (G. nigrocaulis: 86 Mbp/1C; 2n=40) and one with an 18-fold larger genome (G. hispidula: 1550 Mbp/1C; 2n=40) the genomes and transcriptomes have been sequenced, with the aim to find reasons and consequences of evolutionary genome size variation. For these two and four other species the genome size and the chromosome number have been determined and their karyotypes were analysed as to their ploidy level, heterochromatin structures, chromosomal repeat and single copy sequence distribution, centromere- and telomere sequences. Genome size evolution in Genlisea occurred bi-directionally in opposite directions (increase by WGD and retroelement dispersion; decrease by deletion-bias in DSB repair and transposon silencing). Because of similar life style and habitat preferences, the >20-fold genome size variation in this genus is most likely selection-neutral, and many repeats seem to be dispensable. Recurrent WGD preserves essential genomic elements during long-term genome shrinking. High mutation frequency and fast evolution are reflected by centromere (tandem repeat vs. retroelements) and even telomere sequence variation (first infrageneric switch, first C in G-rich strand in plant telomeres). FISH with repeats support dysploid chromosome number reduction in the ancestors of mesoallopolyploid species. For three species more than half or all of the chromosome pairs could be discriminated simultaneously by multicolor FISH applying specific pooling strategies and re-probing of chromosome preparations with single copy or tandem repetitive probes. This paved the way for individual addressing of all chromosomes of these species and for future elucidation of their evolutionary fate. The metatranscriptome of the traps of G. nigrocaulis and G. hispidula revealed a microbiome comprising 92 genera of 19 prokaryotic and eukaryotic phyla as prey or as commensals.
Publications
- Centromere and telomere sequence alterations reflect the rapid genome evolution within the carnivorous plant genus Genlisea. The Plant Journal , 2015
Trung D. Tran, Hieu X. Cao, Gabriele Jovtchev, Pavel Neumann, Petr Novák, Miloslava Fojtová, Giang T.H. Vu, Jiří Macas, Jiří Fajkus, Ingo Schubert, Joerg Fuchs
(See online at https://doi.org/10.1111/tpj.13058) - Chromatin organization and cytological features of carnivorous Genlisea species with large genome size differences. Frontiers in Plant Genetics and Genomics, 2015, 6/613
Trung D. Tran, Hieu X. Cao, Gabriele Jovtchev, Petr Novák, Giang T.H. Vu, Jiří Macas, Ingo Schubert, Joerg Fuchs
(See online at https://doi.org/10.3389/fpls.2015.00613) - Comparative genome analysis reveals divergent genome size evolution in a carnivorous plant genus. The Plant Genome, 2015, 8/3
Giang T. H. Vu, Thomas Schmutzer, Fabian Bull, Hieu X. Cao, Jörg Fuchs, Trung D. Tran, Gabriele Jovtchev, Klaus Pistrick, Nils Stein, Ales Pecinka, Pavel Neumann, Petr Novak, Jiri Macas, Paul H. Dear, Frank R. Blattner, Uwe Scholz, Ingo Schubert
(See online at https://doi.org/10.3835/plantgenome2015.04.0021) - Metatranscriptome analysis reveals host-microbiome interactions in traps of carnivorous Genlisea species. Frontiers in Microbiology, 2015, 6/526
Hieu X. Cao, Thomas Schmutzer, Uwe Scholz, Ales Pecinka, Ingo Schubert, Giang T. H. Vu
(See online at https://doi.org/10.3389/fmicb.2015.00526)
