Dataset Information

Comparative sequence analysis of the Ghd7 orthologous regions revealed movement of Ghd7 in the grass genomes.

ABSTRACT: Ghd7 is an important rice gene that has a major effect on several agronomic traits, including yield. To reveal the origin of Ghd7 and sequence evolution of this locus, we performed a comparative sequence analysis of the Ghd7 orthologous regions from ten diploid Oryza species, Brachypodium distachyon, sorghum and maize. Sequence analysis demonstrated high gene collinearity across the genus Oryza and a disruption of collinearity among non-Oryza species. In particular, Ghd7 was not present in orthologous positions except in Oryza species. The Ghd7 regions were found to have low gene densities and high contents of repetitive elements, and that the sizes of orthologous regions varied tremendously. The large transposable element contents resulted in a high frequency of pseudogenization and gene movement events surrounding the Ghd7 loci. Annotation information and cytological experiments have indicated that Ghd7 is a heterochromatic gene. Ghd7 orthologs were identified in B. distachyon, sorghum and maize by phylogenetic analysis; however, the positions of orthologous genes differed dramatically as a consequence of gene movements in grasses. Rather, we identified sequence remnants of gene movement of Ghd7 mediated by illegitimate recombination in the B. distachyon genome.

SUBMITTER: Yang L

PROVIDER: S-EPMC3503983 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Comparative sequence analysis of the Ghd7 orthologous regions revealed movement of Ghd7 in the grass genomes.

Yang Lu L Liu Tieyan T Li Bo B Sui Yi Y Chen Jinfeng J Shi Jinfeng J Wing Rod A RA Chen Mingsheng M

PloS one 20121121 11

Ghd7 is an important rice gene that has a major effect on several agronomic traits, including yield. To reveal the origin of Ghd7 and sequence evolution of this locus, we performed a comparative sequence analysis of the Ghd7 orthologous regions from ten diploid Oryza species, Brachypodium distachyon, sorghum and maize. Sequence analysis demonstrated high gene collinearity across the genus Oryza and a disruption of collinearity among non-Oryza species. In particular, Ghd7 was not present in ortho ...[more]

PMID: 23185584

Similar Datasets

Project description:BACKGROUND: Retrotransposons are commonly occurring eukaryotic transposable elements (TEs). Among these, long terminal repeat (LTR) retrotransposons are the most abundant TEs and can comprise 50-90% of the genome in higher plants. By comparing the orthologous chromosomal regions of closely related species, the effects of TEs on the evolution of plant genomes can be studied in detail. RESULTS: Here, we compared the composition and organization of TEs within five orthologous chromosomal regions among three grass species: maize, sorghum, and rice. We identified a total of 132 full or fragmented LTR retrotransposons in these regions. As a percentage of the total cumulative sequence in each species, LTR retrotransposons occupy 45.1% of the maize, 21.1% of the rice, and 3.7% of the sorghum regions. The most common elements in the maize retrotransposon-rich regions are the copia-like retrotransposons with 39% and the gypsy-like retrotransposons with 37%. Using the contiguous sequence of the orthologous regions, we detected 108 retrotransposons with intact target duplication sites and both LTR termini. Here, we show that 74% of these elements inserted into their host genome less than 1 million years ago and that many retroelements expanded in size by the insertion of other sequences. These inserts were predominantly other retroelements, however, several of them were also fragmented genes. Unforeseen was the finding of intact genes embedded within LTR retrotransposons. CONCLUSION: Although the abundance of retroelements between maize and rice is consistent with their different genome sizes of 2,364 and 389 Mb respectively, the content of retrotransposons in sorghum (790 Mb) is surprisingly low. In all three species, retrotransposition is a very recent activity relative to their speciation. While it was known that genes re-insert into non-orthologous positions of plant genomes, they appear to re-insert also within retrotransposons, potentially providing an important role for retrotransposons in the evolution of gene function.

Project description:BackgroundCyclospora cayetanensis is an emerging coccidian parasite that causes endemic and epidemic diarrheal disease called cyclosporiasis, and this infection is associated with consumption of contaminated produce or water in developed and developing regions. Food-borne outbreaks of cyclosporiasis have occurred almost every year in the USA since the 1990s. Investigations of these outbreaks are currently hampered due to lack of molecular epidemiological tools for trace back analysis. The apicoplast of C. cayetanensis, a relict non-photosynthetic plastid with an independent genome, provides an attractive target to discover sequence polymorphisms useful as genetic markers for detection and trace back analysis of the parasite. Distinct differences in the apicoplast genomes of C. cayetanensis could be useful in designing advanced molecular methods for rapid detection and, subtyping and geographical source attribution, which would aid outbreak investigations and surveillance studies.MethodsTo obtain the genome sequence of the C. cayetanensis apicoplast, we sequenced the C. cayetanensis genomic DNA extracted from clinical stool samples, assembled and annotated a 34,146 bp-long circular sequence, and used this sequence as a reference genome in this study. We compared the genome and the predicted proteome to the data available from other apicomplexan parasites. To initialize the search for genetic markers, we mapped the raw sequence reads from an additional 11 distinct clinical stool samples originating from Nepal, New York, Texas, and Indonesia to the apicoplast reference genome.ResultsWe identified several high quality single nucleotide polymorphisms (SNPs) and small insertion/deletions spanning the apicoplast genome supported by extensive sequencing reads data, and a 30 bp sequence repeat at the terminal spacer region in a Nepalese sample. The predicted proteome consists of 29 core apicomplexan peptides found in most of the apicomplexans. Cluster analysis of these C. cayetanensis apicoplast genomes revealed a familiar pattern of tight grouping with Eimeria and Toxoplasma, separated from distant species such as Plasmodium and Babesia.ConclusionsSNPs and sequence repeats identified in this study may be useful as genetic markers for identification and differentiation of C. cayetanensis isolates found and could facilitate outbreak investigations.

Dataset Information

Comparative sequence analysis of the Ghd7 orthologous regions revealed movement of Ghd7 in the grass genomes.

Publications

Comparative sequence analysis of the Ghd7 orthologous regions revealed movement of Ghd7 in the grass genomes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets