RRC ID 47753
Author Haramoto Y, Saijyo T, Tanaka T, Furuno N, Suzuki A, Ito Y, Kondo M, Taira M, Takahashi S.
Title Identification and comparative analyses of Siamois cluster genes in Xenopus laevis and tropicalis.
Journal Dev Biol
Abstract Two siamois-related homeobox genes siamois (sia1) and twin (sia2), have been reported in Xenopus laevis. These genes are expressed in the blastula chordin- and noggin-expressing (BCNE) center and the Nieuwkoop center, and have complete secondary axis-inducing activity when over-expressed on the ventral side of the embryo. Using whole genome sequences of X. tropicalis and X. laevis, we identified two additional siamois-related genes, which are tandemly duplicated near sia1 and sia2 to form the siamois gene cluster. Four siamois genes in X. tropicalis are transcribed at blastula to gastrula stages. In X. laevis, the siamois gene cluster is present on both homeologous chromosomes, XLA3L and XLA3S. Transcripts from seven siamois genes (three on XLA3L and four on XLA3S) in X. laevis were detected at blastula to gastrula stages. A transcribed gene, sia1p. S, encodes an inactive protein without a homeodomain. When over-expressed ventrally, all siamois-related genes tested in this study except for sia1p. S induced a complete secondary axis, indicating that X. tropicalis and X. laevis have four and six active siamois-related genes, respectively. Of note, each gene required different amounts of mRNA for full activity. These results suggest the possibility that siamois cluster genes have functional redundancy to endow robustness and quickness to organizer formation in Xenopus species.
Volume 426(2)
Pages 374-383
Published 2017-6-15
DOI 10.1016/j.ydbio.2016.07.015
PII S0012-1606(16)30087-2
PMID 27522305
MeSH Amino Acid Sequence Animals Blastula / metabolism Body Patterning / genetics Chromosome Mapping Conserved Sequence Diploidy Embryo, Nonmammalian / metabolism Gastrula / metabolism Gene Dosage Gene Expression Regulation, Developmental Homeodomain Proteins / genetics* Multigene Family* Organizers, Embryonic Sequence Alignment Sequence Homology, Amino Acid Species Specificity Tetraploidy Wnt Signaling Pathway Xenopus / embryology Xenopus / genetics* Xenopus Proteins / genetics* Xenopus laevis / embryology Xenopus laevis / genetics
IF 2.896
Times Cited 2
Clawed frogs / Newts X. tropicalis