Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
The availability of both the Xenopus tropicalis genome and the soon to be released Xenopus laevis genome provides a solid foundation for Xenopus developmental biologists. The Xenopus community has presently amassed expression data for ∼2,300 genes in the form of published images collected in the Xenbase, the principal Xenopus research database. A few of these genes have been examined in both X. tropicalis and X. laevis and the cross-species comparison has been proven invaluable for studying gene function. A recently published work has yielded developmental expression profiles for the majority of Xenopus genes across fourteen developmental stages spanning the blastula, gastrula, neurula, and the tail-bud. While this data was originally queried for global evolutionary and developmental principles, here we demonstrate its general use for gene-level analyses. In particular, we present the accessibility of this dataset through Xenbase and describe biases in the characterized genes in terms of sequence and expression conservation across the two species. We further indicate the advantage of examining coexpression for gene function discovery relating to developmental processes conserved across species. We suggest that the integration of additional large-scale datasets--comprising diverse functional data--into Xenbase promises to provide a strong foundation for researchers in elucidating biological processes including the gene regulatory programs encoding development.
Figure 1. Identity between the coding sequences of Xenopus laevis and Xenopus tropicalis (light grey) and between Xenopus laevis paralogs (dark grey). Sequence identity was determined using blastn between the 11,095 pairs of the previously delineated orthologs (Yanai et al.,2011). Pairs of X. laevis paralogs were retrieved from a recent study (Hellsten et al.,2007) and compared as for the orthologs.
Reproduced with permission of the Publisher, John Wiley & Sons
Figure 3. Biases of Xenopus research towards genes with higher conservation of sequence and expression. a. Genes with Xenbase expression images as a function of their sequence similarity. The plot indicates the fraction of genes with expression images in Xenbase for the shown sequence similarity ranges. b. Genes with Xenbase expression images as a function of their expression similarity. Expression divergences between X. laevis and X. tropicalis (Yanai et al.,2011) were sorted and split into equally populated bins. The fraction of genes in each bin with Xenbase images is shown.
Reproduced with permission of the Publisher, John Wiley & Sons.
Figure 4. Clustering of comparative gene expression profiles. a. Each plot indicates a plot of genes clustered by Heyer clustering as presented previously (Yanai et al.,2011). The clustering was performed only on X. laevis profiles. Four expression clusters are shown. The unbroken lines correspond to the X. laevis profiles while the dashed lines show the superimposed X. tropicalis profiles. The full clustering is provided in Supporting Information Table S1.
Reproduced with permission of the Publisher, John Wiley & Sons.
Bowes,
Xenbase: gene expression and improved integration.
2010, Pubmed,
Xenbase
Bowes,
Xenbase: gene expression and improved integration.
2010,
Pubmed
,
Xenbase
Cao,
Oct25 represses transcription of nodal/activin target genes by interaction with signal transducers during Xenopus gastrulation.
2008,
Pubmed
,
Xenbase
Chain,
Single-species microarrays and comparative transcriptomics.
2008,
Pubmed
,
Xenbase
Chalmers,
A Xenopus tropicalis oligonucleotide microarray works across species using RNA from Xenopus laevis.
2005,
Pubmed
,
Xenbase
Chimpanzee Sequencing and Analysis Consortium,
Initial sequence of the chimpanzee genome and comparison with the human genome.
2005,
Pubmed
Eroshkin,
Multiple noggins in vertebrate genome: cloning and expression of noggin2 and noggin4 in Xenopus laevis.
2006,
Pubmed
,
Xenbase
Evans,
A mitochondrial DNA phylogeny of African clawed frogs: phylogeography and implications for polyploid evolution.
2004,
Pubmed
,
Xenbase
Fletcher,
Expression of Xenopus tropicalis noggin1 and noggin2 in early development: two noggin genes in a tetrapod.
2004,
Pubmed
,
Xenbase
Hellsten,
Accelerated gene evolution and subfunctionalization in the pseudotetraploid frog Xenopus laevis.
2007,
Pubmed
,
Xenbase
Hirsch,
Xenopus, the next generation: X. tropicalis genetics and genomics.
2002,
Pubmed
,
Xenbase
Kashiwagi,
Xenopus tropicalis: an ideal experimental animal in amphibia.
2010,
Pubmed
,
Xenbase
Ma,
Identification of neurogenin, a vertebrate neuronal determination gene.
1996,
Pubmed
,
Xenbase
Nieber,
Comparative expression analysis of the neurogenins in Xenopus tropicalis and Xenopus laevis.
2009,
Pubmed
,
Xenbase
Sartor,
A new method to remove hybridization bias for interspecies comparison of global gene expression profiles uncovers an association between mRNA sequence divergence and differential gene expression in Xenopus.
2006,
Pubmed
,
Xenbase
Smith,
Expression cloning of noggin, a new dorsalizing factor localized to the Spemann organizer in Xenopus embryos.
1992,
Pubmed
,
Xenbase
Waterston,
Initial sequencing and comparative analysis of the mouse genome.
2002,
Pubmed
Yanai,
Mapping gene expression in two Xenopus species: evolutionary constraints and developmental flexibility.
2011,
Pubmed
,
Xenbase
Yanai,
Comparison of diverse developmental transcriptomes reveals that coexpression of gene neighbors is not evolutionarily conserved.
2009,
Pubmed