• BMB Reports
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• v.53 no.3
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• pp.160-165
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• 2020

The root meristem of Arabidopsis thaliana is protected by the root cap, the size of which is tightly regulated by the balance between the formative cell divisions and the dispersal of the outermost cells. We isolated an enhancer-tagged dominant mutant displaying the short and twisted root by the overexpression of ZINC-FINGER OF ARABIDOPSIS THALIANA1 (ZAT1) encoding an EAR motif-containing zinc-finger protein. The growth inhibition by ZAT1 was shared by ZAT4 and ZAT9, the ZAT1 homologues. The ZAT1 promoter was specifically active in the outermost cells of the root cap, in which ZAT1-GFP was localized when expressed by the ZAT1 promoter. The outermost cell-specific expression pattern of ZAT1 was not altered in the sombrero (smb) or smb bearskin1 (brn1) brn2 accumulating additional root-cap layers. In contrast, ZAT4-GFP and ZAT9-GFP fusion proteins were distributed to the inner root-cap cells in addition to the outermost cells where ZAT4 and ZAT9 promoters were active. Overexpression of ZAT1 induced the ectopic expression of PUTATIVE ASPARTIC PROTEASE3 involved in the programmed cell death. The EAR motif was essential for the growth inhibition by ZAT1. These results suggest that the three related ZATs might regulate the maturation of the outermost cells of the root cap.

• Genomics & Informatics
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• v.4 no.4
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• pp.147-160
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• 2006

GATA transcription factors are widespread eukaryotic regulators whose DNA-binding domain is a class IV zinc finger motif in the form $CX_{2}CX_{17-20}CX_{2}C$followed by a basic region. In fungi, they act as transcriptional activators or repressors in several different processes, ranging from nitrogen source utilization to mating-type switching. Using an in-house bioinformatics portal system, we surveyed 50 fungal and 9 out-group genomes and identified 396 putative fungal GATA transcription factors. The proportion of GATA transcription factors within a genome varied among taxonomic lineages. Subsequent analyses of phylogenetic relationships among the fungal GATA transcription factors, as well as a study of their domain architecture and gene structure, demonstrated high degrees of conservation in type IVa and type IVb zinc finger motifs and the existence of distinctive clusters at least at the level of subphylum. The SFH1 subgroup with a 20-residue loop was newly identified, in addition to six well-defined subgroups in the subphylum Pezizomycotina. Furthermore, a novel GATA motif with a 2f-residue loop ($CX_{2}CX_{21}CX_{2}C$, designated 'zinc finger type IVc') was discovered within the phylum Basidiomycota. Our results suggest that fungal GATA factors might have undergone multiple distinct modes of evolution resulting in diversified cellular modulation in fungi.

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.59-64
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• 2002

A Cryptosporidium parvum sporozoite and oocyst λgt11 cDNA library was screened with a hyperimmune rabbit serum that was developed against insoluble fragments of ultrasonicated oocysts. A clone named Cp22.4.1 encoding a protein of 231 amino acids with 4 zinc-finger domains characterized by a Cys-X2-Cys-X4-His-X4-Cys motif was isolated and characterized. There was a complete match between the sequencing data of the coding region of Cp22.4.1 and the corresponding gene at chromosomal level. Cloning in a pBAD-TOPO-TA expression vector permitted to evaluate the antigenicty of the recombinant His-tagged antigen. This antigen was recognized by 2 out of 5 sera from Cruptosporidium immune calves and not by sera from parasite naive animals.

• Molecules and Cells
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• v.23 no.3
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• pp.316-322
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• 2007

Zinc finger transcription factor genes are a significant fraction of the genes in the vertebrate genome. Here we report the isolation and characterization of a human zinc finger-containing gene, ZNF435, from a fetal brain cDNA library. ZNF435 cDNA is 1290 base pairs in length and contains an open reading frame encoding 349 amino acids with four C2H2-type zinc fingers at its carboxyl terminus and a SCAN motif at its amino terminus. RT-PCR results showed that ZNF435 was expressed in all tested tissues. A ZNF435-GFP fusion protein was located in the nucleus and the four zinc fingers acted as nuclear localization signals (NLSs). ZNF435 was found to be capable of homo-association, and this effect was independent of its zinc fingers. Furthermore, ZNF435 proved to be a transcription repressor as its overexpression in AD293 cells inhibited the transcriptional activities of AP-1.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1279-1287
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• 2006

The purpose of this paper is to present a new algorithm for extracting the consensus pattern, or motif from sequence belonging to the same family. Two methods are considered for feature interval partitioning based on equal probability and equal width interval partitioning. C2H2 zinc finger protein and epidermal growth factor protein sequences are used to demonstrate the effectiveness of the proposed algorithm for motif extraction. For two protein families, the equal width interval partitioning method performs better than the equal probability interval partitioning method.

• The Plant Pathology Journal
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• v.25 no.4
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• pp.381-388
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• 2009

On screening pathogen-resistant soybean, we identified a WRKY type transcription factor named a Glycine max WRKY1 (GmWRKY1). Expression of GmWRKY1 gene was induced in the soybean sprout by Pseudomonas infection. The GmWRKY1 was expressed in all of the tissues with high levels in stems, leaves and developing seeds. The protein Gm WRKY1 contains highly conserved two WRKY DNA-binding domains having two $C_2-H_2$ zinc-finger motif ($C-X_{4-5}-C-X_{22-23}-H-X-H$) in its N-terminal and C-terminal amino acid sequences. In electrophoresis mobility shift assay, the GmWRKY1 protein bound specifically to W-box elements in the promoters of defense related genes. These results demonstrated that GmWRKY1 is one of the soybean WRKY family genes and the plant-specific transcription factors for defense processes.

• Korean Journal of Microbiology
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• v.32 no.2
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• pp.102-108
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• 1994

Autonomously replicating sequence Binding Factor 1(ABF1) is a DNA-binding protein that specifically recognizes the $RTCRYN_5ACG$ at many sites in the yeast genome including the promoter element, mating-type silencer and ARS. To express the intact full-length ABF1 gene in E. coli, the ABF1 gene has been cloned into pMAL-c2 and His-61, Leu-353 and Leu-360 were substituted with other amino acid. ABF1 fusion proteins of wild type ABF1 and H61A, L353R and L360R nutants were purified by amylose resin affinity chromatography. Fusion protein of MBP and ABF1 was digested by Factor Xa and Characterized by gel retardation assay and complementation test. As aresult, we suggested that other DNA binding motif except atypical inc-finger motif is in the middle region of ABF1.

• BMB Reports
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• v.35 no.2
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• pp.194-198
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• 2002

Eukaryotic replication protein A (RPA) is a single-stranded(ss) DNA binding protein with multiple functions in DNA replication, repair, and genetic recombination. The 70-kDa subunit of eukaryotic RPA contains a conserved four cysteine-type zinc-finger motif that has been implicated in the regulation of DNA replication and repair. Recently, we described a novel function for the zinc-finger motif in the regulation of human RPA's ssDNA binding activity through reduction-oxidation (redox). Here, we show that yeast RPA's ssDNA binding activity is regulated by redox potential through its RPA32 and/or RPA14 subunits. Yeast RPA requires a reducing agent, such as dithiothreitol (DTT), for its ssDNA binding activity. Also, under non-reducing conditions, its DNA binding activity decreases 20 fold. In contrast, the RPA 70 subunit does not require DTT for its DNA binding activity and is not affected by the redox condition. These results suggest that all three subunits are required for the regulation of RPA's DNA binding activity through redox potential.

• Animal cells and systems
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• v.6 no.3
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• pp.277-282
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• 2002

Topoisomearse II is an essential enzyme in all organisms with several independent roles in DNA metabolism. Recently, it has been demonstrated that the C-terminal region of topoisomerases II is associated with hetero-logous protein-protein interactions in human and yeast. In this study, we identified that RTP1, a rat homologue of EIA binding protein BS69, is another topoisomerae II interacting protein by yeast two-hybrid screening. RTP1 has an E1A-binding domain and a MYND motif, which are known to be required for transcriptional regulation by binding to other proteins and interaction with the leucine zipper motif of topoisomerase II. The physical interaction between RTP1 and topoisomerase ll$\alpha$ was examined by GST pull-down assay in vitro. The expression level of RTP1 peaks in S phase as that of topoisomerase ll$\alpha$. These results suggest that the interaction between topoisomerase ll$\alpha$ and RTP1 might play an important role in regulating the transcription of genes involved in DNA metabolism in higher eukaryotes.

• Journal of Plant Biotechnology
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• v.35 no.3
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• pp.177-183
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• 2008

Ac/Ds mutant lines of this study were transgenic rice plants, each of which harbored the maize transposable element Ds together with a GUS coding sequence under the control of a promoterless(Ds-GUS). We selected the mutants that were GUS expressed lines, because the GUS positive lines will be useful for identifying gene function in rice. One of these mutants was identified knock-out at Oszinc626(NP_001049991) gene, encoding a RING-H2 zinc-finger protein, by Ds insertion. In this mutant, while primary root development is normal, secondary root development from lateral root was very poor and seed development was incomplete compare with normal plant. RING zinc-finger proteins play important roles in the regulation of development in a variety of organisms. In the plant kingdom, a few genes encoding RING zinc-finger proteins have been documented with visible effects on plant growth and development. The consensus of the RING-H2(C3-H2-C3 type) domain for this group of protein is $Cys-X_2-Cys-X_{28}-Cys-X-His-X_2-His-X_2-Cys-X_{14}-Cys-X_2-Cys$. Oszinc626 encodes a predicted protein product of 445 amino acids residues with a molecular mass of 49 kDa, with a RING-zinc-finger motif located at the extreme end of the C-terminus. RT-PCR analysis indicated that the expression of Oszinc626 gene was induced by IAA, cold, dehydration, high-salinity and abscisic acid, but not by 2,4-D, and the transcription of Oszinc626 gene accumulated primarily in rice immature seeds, root meristem and shoots. The gene accumulation patterns were corresponded with GUS expression.