XSIP1, a member of two-handed zinc finger proteins, induced anterior neural markers in Xenopus laevis animal cap.
We characterized Xenopus SIP1 (XSIP1), Smad interacting protein, from activin-treated animal caps by differential screening. The XSIP1 is very similar to mouse SIP1 in the protein coding region including the zinc finger domain and homeodomain. The expression pattern was analyzed by RT-PCR and whole mount in situ hybridization. XSIP1 expression was initially restricted to the dorsal marginal zone in the late gastrula and was subsequently expressed at the lateral edge of neural plate and, in the tailbud stage, in the forebrain, neural tube, and eye. Overexpression of XSIP1 at the animal caps resulted in activation of anterior neural markers without mesodermal markers. Ectopic expression of XSIP1 induced enlargement of neural cells and disordered eye formation. In addition to abnormal head phenotypes, many embryos were short-tailed. Our findings suggest that XSIP1 is a transcriptional repressor, which may be involved in the activin-dependent signal pathway.
Eisaki
A
A
Department of Life Science (Biology), CREST, Japan Science and Technology Corporation (JST), University of Tokyo, 3-8-1 Komaba, Tokyo, Meguro, 153-8902, Japan.
Kuroda
H
H
Fukui
A
A
Asashima
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015415:Biomarkers; D046508:Culture Techniques; D004076:Digoxigenin / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009474:Neurons; D016366:Open Reading Frames; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology*; D016335:Zinc Fingers
D015415:Biomarkers; D018398:Homeodomain Proteins; D012097:Repressor Proteins; D029867:Xenopus Proteins; C492364:ZEB2 protein, Xenopus; D004076:Digoxigenin