Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P51532 (transcriptional activator)
 6,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The transcription factor E2F regulates the expression of genes involved in the progression of G1/S transition and DNA replication in mammalian cells. We cloned and characterized a cDNA (NtE2F) corresponding to a E2F homolog of tobacco (Nicotiana tabacum). The transcription of NtE2F was induced as cells progressed from G1 to the S phase and expressed much earlier than that of the proliferating cell nuclear antigen (PCNA) gene. We demonstrated that NtE2F can interact with the tobacco retinoblastoma (Rb)-related protein in a yeast two-hybrid assay. To further characterize NtE2F, the trans-activation activity of NtE2F was examined by using a transient assay in the tobacco Bright Yellow-2 (BY-2) cells with NtE2F fused to the DNA-binding domain of the veast transcriptional activator GAL4. NtE2F activated the transcription of the beta-glucuronidase (GUS) reporter gene driven by a cauliflower mosaic virus (CaMV) 35S core promoter containing the GAL4-binding sequence. This is the first report of the identification of a functionally equivalent E2F-like gene in plants.
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PMID:Isolation and characterization of the E2F-like gene in plants. 1057 Oct 72

Trichomes of Arabidopsis are single-celled epidermal hair that are a useful model for studying plant cell fate determination. Trichome initiation requires the activity of the GLABROUS1 (GL1) gene whose expression in epidermal and trichome cells is dependent on the presence of a 3'-cis-regulatory element. Using a one-hybrid screen, we have isolated a cDNA, which encodes for a protein, GL1 enhancer binding protein (GeBP), that binds this regulatory element in yeast and in vitro. GeBP and its three homologues in Arabidopsis share two regions: a central region with no known motifs and a C-terminal region with a putative leucine-zipper motif. We show that both regions are necessary for trans-activation in yeast. A translational fusion with the Yellow Fluorescent Protein (YFP) indicates that GeBP is a nuclear protein whose localization is restricted to, on average, 3-5 subnuclear foci that might correspond to nucleoli. Transcriptional fusion with the GUS reporter indicates that GeBP is mainly expressed in vegetative meristematic tissues and in very young leaf primordia. We looked at GeBP expression in plants mutated in or misexpressing KNAT1, a KNOX gene, expressed in the shoot apical meristem and downregulated in leaf founder cells, and found that GeBP transcript level is regulated by KNAT1 suggesting that KNAT1 is a transcriptional activator of GeBP. This regulation suggests that GeBP is acting as a repressor of leaf cell fate.
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PMID:GeBP, the first member of a new gene family in Arabidopsis, encodes a nuclear protein with DNA-binding activity and is regulated by KNAT1. 1253 44