RRC ID 47743
Author Suzuki A, Uno Y, Takahashi S, Grimwood J, Schmutz J, Mawaribuchi S, Yoshida H, Takebayashi-Suzuki K, Ito M, Matsuda Y, Rokhsar D, Taira M.
Title Genome organization of the vg1 and nodal3 gene clusters in the allotetraploid frog Xenopus laevis.
Journal Dev Biol
Abstract Extracellular factors belonging to the TGF-β family play pivotal roles in the formation and patterning of germ layers during early Xenopus embryogenesis. Here, we show that the vg1 and nodal3 genes of Xenopus laevis are present in gene clusters on chromosomes XLA1L and XLA3L, respectively, and that both gene clusters have been completely lost from the syntenic S chromosome regions. The presence of gene clusters and chromosome-specific gene loss were confirmed by cDNA FISH analyses. Sequence and expression analyses revealed that paralogous genes in the vg1 and nodal3 clusters on the L chromosomes were also altered compared to their Xenopus tropicalis orthologs. X. laevis vg1 and nodal3 paralogs have potentially become pseudogenes or sub-functionalized genes and are expressed at different levels. As X. tropicalis has a single vg1 gene on chromosome XTR1, the ancestral vg1 gene in X. laevis appears to have been expanded on XLA1L. Of note, two reported vg1 genes, vg1(S20) and vg1(P20), reside in the cluster on XLA1L. The nodal3 gene cluster is also present on X. tropicalis chromosome XTR3, but phylogenetic analysis indicates that nodal3 genes in X. laevis and X. tropicalis were independently expanded and/or evolved in concert within each cluster by gene conversion. These findings provide insights into the function and molecular evolution of TGF-β family genes in response to allotetraploidization.
Volume 426(2)
Pages 236-244
Published 2017-6-15
DOI 10.1016/j.ydbio.2016.04.014
PII S0012-1606(16)30041-0
PMID 27720224
MeSH Animals Biological Evolution Chromosome Mapping Evolution, Molecular Gene Deletion Gene Duplication Genome* In Situ Hybridization, Fluorescence Multigene Family* Phylogeny Pseudogenes Species Specificity Synteny Tetraploidy Transforming Growth Factor beta / genetics* Xenopus / genetics Xenopus Proteins / genetics* Xenopus laevis / genetics*
IF 2.896
Times Cited 1
Clawed frogs / Newts X. tropicalis