XB-ART-6818Mech Dev 2002 Aug 01;1161-2:177-81. doi: 10.1016/s0925-4773(02)00129-6.
Show Gene links Show Anatomy links
Cloning and developmental expression of Baf57 in Xenopus laevis.
Mammalian and Drosophila homologues of Baf57 have been previously isolated as being a subunit of SWI/SNF-like chromatin remodeling complexes. Here, we report the cloning and developmental expression of Xenopus Baf57. We isolated XBaf57 by using an expression cloning approach to identify novel modulators of Xenopus Smad7. XBaf57 co-operates with XSmad7 by increasing the expression of neural markers in ectodermal explants. XBaf57 is expressed in the ectoderm and pre-involuting mesoderm during gastrula stages and in the central nervous system during neurula and tailbud stages. These results raise the possibility that XBaf57 (or XBaf57-containing chromatin remodelling complexes) may be involved in the process of neural induction during Xenopus embryonic development.
PubMed ID: 12128220
Article link: Mech Dev
Species referenced: Xenopus laevis
Genes referenced: actl6a eef1a2 hoxb9 nrp1 smad7 smarce1 snai2
Article Images: [+] show captions
|Fig. 4. Developmental expression of XBaf57. (A) RT-PCR analysis of total embryo RNA prepared at the indicted stages. XBaf57 transcripts are detected maternally and throughout gastrula, neurula and tadpole stages. RT- is a negative control without reverse transcriptase during cDNA synthesis. Histone was used as loading control. (B–I) Whole mount in situ hybridization analysis of XBaf57. (B) Lateral view and (C) sagittal section of a stage 10.5 embryo showing XBaf57 expression in the ectoderm and marginal zone but not the vegetal pole. (D) Vegetal view and (E) sagittal section of a stage 12 embryo confirming the ectodermal expression of XBaf57. The black arrowheads indicate the position of the dorsal blastopore lip. (F) Dorsal view of a stage 14 embryo showing expression in the neural plate and border between the neural plate and epidermis. (G) Dorsal view of a stage 24 embryo. XBaf57 is expressed along the central nervous system and eye. (H) Lateral view of a stage 30 embryo showing expression in the branchial arches, otic vesicle, tailbud and vascular structures such as the intersomitic vessels and posterior cardinal vein. (I) Lateral view of a stage 30 cleared embryo reveals weaker expression in the vitelline vascular network. In (F–I) anterior is to the left.|
|Fig. 2. Clone 504-1F (XBaf57) co-operates with XSmad7 to induce neural markers in animal caps. RT-PCR of animal caps injected with the indicated amounts of XSmad7 and XBaf57 RNA. The expression of the neural markers Nrp1 and Otx increased when XBaf57 was co-injected with XSmad7. XBaf57 alone did not significantly induce neural markers. The neural crest marker slug, the posterior neural marker Hoxb9 and the mesodermal marker muscle actin were not induced by XBaf57 alone or in combination with XSmad7. All samples were analyzed at stage 20. RT 2 is a negative control where no reverse transcriptase was added to embryo RNA during cDNA synthesis. EF1a was used as loading control.|