POU domain transcription factors that share a conserved DNA-binding domain, POU domain, are important regulators for the development of embryos in various animal species. A novel zebrafish POU domain gene, poulll has ...POU domain transcription factors that share a conserved DNA-binding domain, POU domain, are important regulators for the development of embryos in various animal species. A novel zebrafish POU domain gene, poulll has been cloned. The poullll cDNA is 2080 kb in length and encodes a putative polypeptide of 596 ammo acids. It is placed into class II POU family since it shares a high degree of homology with the known members of this family. Northern hybridization identifies a major transcript of approximately 2.1 kb that was present in embryos at the single-cell stage throughout 24 h postfertilization. The whole mount in situ hybridization shows that poulll transcripts are present in the single-cell embryos, strongly suggesting that these transcripts are of maternal origin. During early development of the embryos, poulll mRNA was ubiquitously distributed in all cells and tissues. The transcripts are gradually limited to brains and become completely undetectable by day 3. To our knowledge, poulll is the展开更多
Fibronectins (FNs) are major extracellular proteins in blood plasma and many tissues of vertebrates, and play important roles in adhesion, migration and differentiation of cells. We have identified a novel variant (FN...Fibronectins (FNs) are major extracellular proteins in blood plasma and many tissues of vertebrates, and play important roles in adhesion, migration and differentiation of cells. We have identified a novel variant (FN3) of fibronectin in zebrafish. FN3 mRNA is abundant, as detected by whole-mount in situ hybridization, in the presomitic mesoderm and the newly formed somites, but less abundant in mature somites. Ectopic expression of Sonic Hedgehog (SHH) results in a decrease of FN3 expression, whereas the expression level of FN3 increases in the flhi mutants that lack the notochord. Our results suggest that FN3 may be involved in the formation of somites, but during somite differentiation its expression needs to be downregulated by signals derived from the axial tissues.展开更多
基金This work was supported in part by the National Key Basic Research and Development Program (Grant No. G19990756)the National Natural Science Foundation of China (Grant Nos. 30025020 and 39970360) and the "985" Program.
文摘POU domain transcription factors that share a conserved DNA-binding domain, POU domain, are important regulators for the development of embryos in various animal species. A novel zebrafish POU domain gene, poulll has been cloned. The poullll cDNA is 2080 kb in length and encodes a putative polypeptide of 596 ammo acids. It is placed into class II POU family since it shares a high degree of homology with the known members of this family. Northern hybridization identifies a major transcript of approximately 2.1 kb that was present in embryos at the single-cell stage throughout 24 h postfertilization. The whole mount in situ hybridization shows that poulll transcripts are present in the single-cell embryos, strongly suggesting that these transcripts are of maternal origin. During early development of the embryos, poulll mRNA was ubiquitously distributed in all cells and tissues. The transcripts are gradually limited to brains and become completely undetectable by day 3. To our knowledge, poulll is the
基金the National Natural Science Foundation ofChina (Grant Nos. 30025020 and 39970360), TRAPOYT of MOE, and the "863" Program (Grant No. 2001AA221241).
文摘Fibronectins (FNs) are major extracellular proteins in blood plasma and many tissues of vertebrates, and play important roles in adhesion, migration and differentiation of cells. We have identified a novel variant (FN3) of fibronectin in zebrafish. FN3 mRNA is abundant, as detected by whole-mount in situ hybridization, in the presomitic mesoderm and the newly formed somites, but less abundant in mature somites. Ectopic expression of Sonic Hedgehog (SHH) results in a decrease of FN3 expression, whereas the expression level of FN3 increases in the flhi mutants that lack the notochord. Our results suggest that FN3 may be involved in the formation of somites, but during somite differentiation its expression needs to be downregulated by signals derived from the axial tissues.
