Year-end Sale % OFF 
Abstract
Plasmodiophora brassicae is a soil-borne pathogen that attacks roots of cruciferous plants causing clubroot disease. The pathogen belongs to the Plasmodiophorida order in Phytomyxea. Here we used long-read SMRT technology to clarify the P. brassicae e3 genomic constituents along with comparative and phylogenetic analyses. Twenty contigs representing the nuclear genome and one mitochondrial (mt) contig were generated, together comprising 25.1 Mbp. Thirteen of the 20 nuclear contigs represented chromosomes from telomere to telomere characterized by [TTTTAGGG] sequences. Seven active gene candidates encoding synaptonemal complex-associated and meiotic-related protein homologs were identified, a finding that argues for possible genetic recombination events. The circular mt genome is large (114,663 bp), gene dense and intron rich. It shares high synteny with the mt genome of Spongospora subterranea, except in a unique 12 kb region delimited by shifts in GC content and containing tandem minisatellite- and microsatellite repeats with partially palindromic sequences. De novo annotation identified 32 protein-coding genes, 28 structural RNA genes and 19 ORFs. ORFs predicted in the repeat-rich region showed similarities to diverse organisms suggesting possible evolutionary connections. The data generated here form a refined platform for the next step involving functional analysis, all to clarify the complex biology of P. brassicae.
Highlights
Unicellular eukaryotes or protists can be found in any habitat worldwide and fossil records are available for certain taxa where some are dated as early as the Precambrian period[1]
We present new data based on twenty contigs representing the nuclear genomic content of P. brassicae e3 and one contig covering the entire mitochondrial genome generated by this approach
The [TTTTAGGG] or T4AG3 telomeric sequences of P. brassicae (Supplementary Fig. S1) are identical with those found in Chlamydomonas reinhardtii, the green alga[25] and Theileria annulata, an apicomplexan animal parasite[26]
Summary
Unicellular eukaryotes or protists can be found in any habitat worldwide and fossil records are available for certain taxa where some are dated as early as the Precambrian period[1]. Genomic information of high quality is crucial for enhancing our understanding of important evolutionary events, which could give us insights into related organisms together with events behind lost and gained traits Such information could in case of plant pathogens be extra valuable for development of durable control strategies. We previously made a de novo genome assembly of the P. brassicae strain e3 based on a combination of Illumina and 454 sequencing approaches[16] This achievement was followed by genome information for isolates from Canada, China and Germany based on similar technologies[21,22,23]. The assembly and de-novo annotation of the mitochondrial genome revealed a 114,663 bp large genome with a complex sequence organization and a distinct 12 kb repeat-rich region These findings emphasize the value of long-reads in resolving unrecognized genomic variation and highlight the importance of distinguishing biological from technical sequence differences
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
