The Alliance is pleased to announce the release of Xenopus data from Xenbase. These amphibians are an important tetrapod model, spanning the evolutionary gap between the mammalian (human, mouse, and rat) and zebrafish data already included in the Alliance. Xenopus have long been used in developmental and cell biology, and two species are widely studied. The African clawed frog, X. laevis (abbreviated Xla in the Alliance) is an allotetraploid (2n = 36) of hybrid origin. The resulting X. laevis genome has a set of ‘long’ and ‘short’ chromosomes and gene symbols are therefore appended with ‘.L’ or ‘.S’ denoting on which chromosome pair they reside. The second Xenopus species, the Western clawed frog X. tropicalis (Xtr), is a conventional diploid (2n=20), and is increasingly used in human disease modelling.
Data for both Xenopus species are organized on individual gene pages that feature data such as gene descriptions, orthology to human and other species, disease associations for orthologs, an expression ribbon view, and a Sequence Feature Viewer. In order to fully support Xenbase orthology, a subset of X. tropicalis orthology calls from DIOPT 8 have been merged into our current DIOPT 9 dataset. DIOPT 8 returns the TreeFam and RoundUp data sources, but only for X. tropicalis. Orthology calls by Xenbase curators are also included under the new algorithm category “Xenbase.”