XB-ART-24293Proc Natl Acad Sci U S A December 1, 1991; 88 (23): 10642-6.
Expression of GATA-binding proteins during embryonic development in Xenopus laevis.
Proteins that recognize the core sequence GATA are important regulators of hematopoietic-specific gene transcription. We have characterized cDNAs encoding the Xenopus laevis homologues of three related transcription factors, designated GATA-1, -2, and -3. Comparative sequence analysis reveals strong conservation of the zinc-finger DNA-binding domain among all vertebrate GATA-binding proteins. GATA-2 and GATA-3 polypeptides are homologous throughout their entire sequences, whereas GATA-1 sequence is conserved only in the region responsible for DNA binding. In Xenopus, RNAs encoding GATA-binding proteins are expressed in both larval and adult erythroid cells. GATA-1, -2, and -3 RNAs are first detectable in early gastrula (Nieuwkoop developmental stage 11). This is earlier than the appearance of the early larval alpha T1 globin RNA (stage 15), beta T1 globin RNA (stage 26), or blood island formation (stage 30). The expression of GATA-1, -2, and -3 in early development may signal an early commitment of mesoderm to form hematopoietic tissue.
PubMed ID: 1961730
PMC ID: PMC52986
Article link: Proc Natl Acad Sci U S A
Species referenced: Xenopus laevis
Genes referenced: agtr1 gata1 gata2 gata3 myod1
Article Images: [+] show captions
|FIG. 1. Comparison of the predicted amino acid sequences of vertebrate GATA-binding proteins. The zinc-finger DNA-binding domain is underlined. The conserved amino acids outside the DNA-binding domain are marked (*). x, Xenopus; c, chicken; mn, mouse; h, human. (For sequences, see refs. 14, 15, 18-23, and 46.)|
|FIG. 2. Distinctive features of the finger region of the vertebrate GATA-binding proteins. Amino acids 314-409 of the finger domains of mGATA-1 are shown at the top with positions of divergence noted by X. Amino acid residues characteristic of the various GATA family members are shown below. Intervening sequence position is marked based on the structure of the murine GATA-1 gene (30).|
|FIG. 3. Expression of GATA-binding protein genes in Xenopus erythroid cells. Total cell RNAs (15 ,ug) were subjected to Northern blot analysis and hybridized with a xGATA-1B cDNA probe (A) or a xGATA-3 probe (B). Cells studied include Xenopus eggs or oocytes (egg), tadpole erythroid cells, adult erythroid cells, adult reticulocytes (retic), XTC cell line, XL cell line, murine erythroleukemia cells (MEL), and human erythroleukemia cells (K562).|
|FIG. 4. Developmental expression of xGATA-binding protein and larval globin genes. (A) Total cellular RNAs (1 /g) from staged Xenopus embryos were subjected to RT-PCR using specific primers for ,T1 globin, xGATA-1, xGATA-2, xGATA-3, and xMyoD. Controls consisted of RT-PCR products from total RNA from Xenopus adult erythroid cells and HeLa cells and H20. Lanes: 1, oocyte; 2, 4-cell embryo; 3, 32-cell embryo; 13, erythroid cells; 14, HeLa cells; 15, H20. The Nieuwkoop stage is indicated in the following lanes. Lanes: 4, 7; 5, 9; 6, 11; 7, 12.5; 8, 13; 9, 18; 10, 24; 11, 26; 12, 30. (B) Total cellular RNAs from staged Xenopus embryos were subjected to Northern blot analysis and hybridized with an aT1 globin cDNA probe (37). Nieuwkoop stages are as follows. Lanes: 1, 10.5; 2, 12; 3, 13; 4, 15; 5, 17; 6, 20; 7, 24; 8, 26; 9, 30; 10, 33; 11, 38; 12, erythroid-cell control.|
References [+] :
Banville, The nucleotide sequence of the mRNA encoding a tadpole beta-globin polypeptide of Xenopus laevis. 1983, Pubmed, Xenbase