Identification of a second Xenopus twisted gastrulation gene.
Twisted Gastrulation (Tsg) is a secreted molecule which regulates BMP signalling in the extracellular space as part of an evolutionarily conserved network of interacting proteins. In Xenopus, maternal xTsg mRNA can be found throughout the early embryo. After gastrulation, xTsg is expressed as part of the BMP4 synexpression group until late tadpole stages. Here we report the identification of a second Xenopus Tsg gene (xTsg-2). Xenopus Tsg-2 is highly homologousto xTsg. In particular, amino acid residues which have been shown to be required for the binding of xTsg to BMP and to Chordin are conserved. The expression of Xenopus Tsg-2 mRNA was restricted to late stages of embryonic development; it was detected at tadpole stages in lateral plate mesoderm, neural crest, branchial arches and head mesenchyme. In microinjection experiments, the activity of xTsg-2 mRNA was similar to that of xTsg. We conclude that two Tsg genes act in distinct temporal and spatial territories in the course of Xenopus embryonic development.
Howard Hughes Medical Institute, and Department of Biological Chemistry, University of California, Los Angeles, CA 90095-1662, USA.
Michael
M
Oelgeschläger
Uyen
U
Tran
Kristina
K
Grubisic
Edward M
EM
De Robertis
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D047908:Intracellular Signaling Peptides and Proteins; D008845:Microinjections; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D029867:Xenopus Proteins / Q000737:chemistry / Q000235:genetics*; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics*
D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D012333:RNA, Messenger; C477670:TWSG1 protein, Xenopus; D029867:Xenopus Proteins