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At least 649 records · Page 36Linked to original sources
PubMed2001

Identification of a p53 response element in the promoter region of the hMSH2 gene required for expression in A2780 ovarian cancer cells.

Defects in the human MSH2 mismatch repair system have been implicated in cellular mutagenesis, tumorigenesis, and chemotherapeutic resistance. The current studies characterized the 5' upstream proximal promoter region of the hMSH2 gene using transient transfection of A2780 ovarian cancer cells. Serial deletions of a 1.88-kb fragment of the proximal promoter region of the hMSH2 gene revealed that promoter activity was restricted to the first -281 bp. Targeted deletions within this -281 bp region coupled with specific sequence mutagenesis identified a response element for the p53 tumor suppressor protein located between -242 and -222 bp. The -242 hMSH2 p53 element is configured as a direct tandem repeat palindrome with 80% homology to the p53 consensus binding sequence. Co-transfection of an hMSH2 reporter and p53 expression vector into the p53-null cell line SK-OV-3 produced 10-fold enhanced transcription, which was lost when the -242 to -222 p53 binding site was mutated. These results clearly demonstrate the presence of a previously unidentified p53 response element in the hMSH2 proximal promoter. Its location at -242 bp upstream of the start site of transcription is distinct from two previously reported p53 sites at -447 and -416, which transactivate in Saos-2 cells (Scherer, S. J., Maier, S. M., Seifert, M., Hanselmann, R. G., Zang, K. D., Muller-Hermelink, H. K., Angel, P., Welter, C., and Schartl, M. (2000) J. Biol. Chem. 275, 37469-37473). Finally, in sharp contrast to their activity in Saos-2 cells, deletion of the -447 and -416 sites in A2780 cells had no effect on hMSH2 promoter activity. Thus, it appears that p53 regulates hMSH2 expression through multiple cell type-specific DNA response elements.

Base Sequence↗
PubMed1995

Involvement of multiple cis elements in basal- and alpha-adrenergic agonist-inducible atrial natriuretic factor transcription. Roles for serum response elements and an SP-1-like element.

In the present study, cis elements in the 5'-flanking sequence (FS) of the rat atrial natriuretic factor (ANF) gene involved in regulating basal and alpha 1-adrenergic-inducible transcription were investigated. Truncation analyses using ANF-luciferase reporter constructs transfected into primary neonatal rat cardiac myocytes showed that an A/T-rich serum response element (SRE) at -114 bp of the ANF 5'-FS, which bound serum response factor (SRF), was required for basal and inducible transcription. In constructs composed of 134 bp of rat ANF 5'-FS driving luciferase (ANF-134Luc), mutations in the SRE at -114 bp disrupted SRF binding and ANF promoter activity. However, the same mutations in ANF-638Luc had little effect, suggesting a collaborating role for more distal sequences, such as the other SRE in ANF-638 at -406 bp. In ANF-638Luc, mutations in the SRE at -406 bp that disrupted SRF binding to that site decreased ANF reporter activity by only 25%; however, mutating both of the SREs completely blocked alpha 1-adrenergic-inducible activity. Mutation analyses showed that an ... (SP-1)-like site at -69 bp, shown previously to confer inducibility in reporters with 134 bp of ANF 5'-FS, was not required in ANF-638Luc. However, double mutants in the SP-1-like region and either SRE completely blocked alpha 1-adrenergic-inducible ANF promoter activity. These findings emphasize that no single element is responsible for alpha 1-adrenergic agonist-regulated ANF transcription but that the SREs at -114 and -406 bp and the SP-1-like sequence at -69 bp mediate the effect in collaboration.

Adrenergic alpha-Agonists↗
PubMed2002

Characterization and functional analysis of cAMP response element modulator protein and activating transcription factor 2 (ATF2) isoforms in the human myometrium during pregnancy and labor: identification of a novel ATF2 species with potent transactivation properties.

There is now extensive evidence to indicate that components of the cAMP signaling pathway are up-regulated in the human myometrium during pregnancy so as to potentiate the maintenance of uterine quiescence until term. In many tissue and cell types, increased signaling of the cAMP pathway results in profound changes in gene expression that are catalyzed via stimulation of PKA and activation of cAMP-dependent transcription factors that bind cAMP response elements (CREs) within the promoter regions of affected genes. In the myometrium, these CRE containing genes include beta2-adrenoceptor, cyclo-oxygenase 2, oxytocin receptor, and connexin-43. In preliminary investigations, we reported the differential expression of members of the cAMP bZIP protein family in the myometrium during pregnancy and labor. In this present study, we have now identified and functionally characterized these proteins with respect to myometrial gene expression. We report the identification of a 39,000 mol wt CRE response element modulator protein (CREM)tau2alpha protein having both transactivation and transrepressor properties whose expression is sequentially decreased in the myometrium during gestation and parturition. In contrast, expression of a myometrial 28,000 mol wt CREMalpha protein having only transrepressor actions progressively increased in the myometrium during pregnancy and labor. Similarly, we have isolated two ATF2 proteins of 60,000 and 28,000 mol wts, which represent full-length ATF2 and a novel small isoform of ATF2 that we have termed ATF2-small (ATF2-sm). These proteins are potent transactivators of gene expression and appear to be spatially expressed within the myometrium of the upper and lower uterine regions. The identification and functional characterization of these basic region/leucine zipper proteins in the myometrium may provide further insight into the molecular mechanisms regulating uterine activity during fetal maturation and parturition.

Activating Transcription Factor 2↗
PubMed2002

Transcriptional regulation of the MHC class II trans-activator (CIITA) promoter III: identification of a novel regulatory region in the 5'-untranslated region and an important role for cAMP-responsive element binding protein 1 and activating transcription factor-1 in CIITA-promoter III transcriptional activation in B lymphocytes.

The class II trans-activator (CIITA), which acts as a master regulator for expression of MHC class II genes, is expressed constitutively in mature B cells. This constitutive expression of CIITA is driven by CIITA promoter III (CIITA-PIII). However, little is known about the factors that control the B cell-mediated trans-activation of CIITA-PIII. In this study using B cells we have identified several cAMP-responsive elements (CREs) in the proximal promoter and in the 5'-untranslated region (5'-UTR) that are involved in the activation of CIITA-PIII. We show that activating transcription factor (ATF)/CRE binding protein (CREB) factors bind to the CREs in vitro and in vivo. Notably, our results also reveal that the 5'-UTR of CIITA-PIII functions as an important regulatory region in B lymphocytes. Furthermore, transient cotransfections of a CIITA-PIII luciferase reporter construct with either CREB-1 or ATF-1 boost CIITA-PIII trans-activation in a dose-dependent manner, which was further enhanced by addition of general coactivator CREB-binding protein. Transient transfections using mutant CIITA-PIII luciferase reporter constructs that either lack the (5'-UTR) or abolish binding of CREB-1 and ATF-1 to the CRE located in activation response element-2, displayed severely reduced promoter activity in B cells. A similar successive deletion of the CREs resulted in a subsequent reduction of CREB-1-induced activity of CIITA-PIII in B cells. Together our results argue for an important role of ATF/CREB factors and the 5'-UTR of CIITA-PIII in the trans-activation of CIITA-PIII in B cells.

5' Untranslated Regions↗
PubMed2005

Transgenic cAMP response element reporter flies for monitoring circadian rhythms.

The cAMP response Element (CRE)-binding protein (CREB) is involved in many adaptive behaviors, including circadian rhythms. In order to assess CREB activity in vivo, we made transgenic flies carrying a CRE-luciferase reporter and showed that this reporter is CRE and dCREB2 responsive. dCREB2 is the Drosophila homolog of mammalian CREB?CREM. The transgenic luciferase activity cycles with a 24-h periodicity, suggesting that dCREB2 and period are somehow linked. The CRE-luciferase reporter is a useful monitor of circadian activity, and mutations can be found that affect its periodicity, baseline activity, or amplitude. Analysis of such mutations should reveal information about how particular genes affect the molecular machinery of circadian cycling and how different genes affect the activity of dCREB2.

Animals↗
PubMed2005

Gonadotropin-releasing hormone (GnRH) positively regulates corticotropin-releasing hormone-binding protein expression via multiple intracellular signaling pathways and a multipartite GnRH response element in alphaT3-1 cells.

CRH-binding protein (CRH-BP) binds CRH with high affinity and inhibits CRH-mediated ACTH release from anterior pituitary corticotrope-like cells in vitro. In female mouse pituitary, CRH-BP is localized not only in corticotropes, but is also expressed in gonadotropes and lactotropes. To investigate the functional significance of gonadotrope CRH-BP, we examined the molecular mechanisms underlying GnRH-regulated CRH-BP expression in alphaT3-1 gonadotrope-like cells. CRH-BP is endogenously expressed in alphaT3-1 cells, and quantitative real-time RT-PCR and ribonuclease protection assays demonstrate that GnRH induces a 3.7-fold increase in CRH-BP mRNA levels. GnRH also induces intracellular CRH-BP (2.0-fold) and secreted CRH-BP (5.3-fold) levels, as measured by [125I]CRH:CRH-BP chemical cross-linking. Transient transfection assays using CRH-BP promoter-luciferase constructs indicate that GnRH regulation involves protein kinase C-, ERK- and calcium-dependent signaling pathways and is mediated via a multipartite GnRH response element that includes activator protein 1 and cAMP response element (CRE) sites. The CRE site significantly contributes to GnRH responsiveness, independent of protein kinase A, representing a unique form of multipartite GnRH regulation in alphaT3-1 cells. Furthermore, EMSAs indicate that alphaT3-1 nuclear proteins specifically bind at activator protein 1 and CRE sites. These data demonstrate novel regulation of pituitary CRH-BP, highlighting the importance of the pituitary gonadotrope as a potential interface between the stress and reproductive axes.

Activating Transcription Factor 2↗
PubMed1999

ACGT-containing abscisic acid response element (ABRE) and coupling element 3 (CE3) are functionally equivalent.

ACGT-containing ABA response elements (ABREs) have been functionally identified in the promoters of various genes. In addition, single copies of ABRE have been found to require a cis-acting, coupling element to achieve ABA induction. A coupling element 3 (CE3) sequence, originally identified as such in the barley HVA1 promoter, is found approximately 30 bp downstream of motif A (ACGT-containing ABRE) in the promoter of the Osem gene. The relationship between these two elements was further defined by linker-scan analyses of a 55 bp fragment of the Osem promoter, which is sufficient for ABA-responsiveness and VP1 activation. The analyses revealed that both motif A and CE3 sequence were required not only for ABA-responsiveness but also for VP1 activation. Since the sequences of motif A and CE3 were found to be similar, motif-exchange experiments were carried out. The experiments demonstrated that motif A and CE3 were interchangeable by each other with respect to both ABA and VP1 regulation. In addition, both sequences were shown to be recognized by a VP1-interacting, ABA-responsive bZIP factor TRAB1. These results indicate that ACGT-containing ABREs and CE3 are functionally equivalent cis-acting elements. Furthermore, TRAB1 was shown to bind two other non-ACGT ABREs. Based on these results, all these ABREs including CE3 are proposed to be categorized into a single class of cis-acting elements.

Abscisic Acid↗
PubMed2003

Identification of Translin/Trax complex as a glucose response element binding protein in liver.

Previously, we found a novel protein factor in the livers of rats fed a high-carbohydrate diet, which binds to the major late transcription factor (MLTF)-like site within the glucose response element (GRE) of the liver-type pyruvate kinase (L-PK) gene [J. Biol. Chem. 274 (1999) 1100]. This factor, termed glucose response element binding protein (GRBP), exists in both liver cytosol and nucleus. In order to identify GRBP, we purified to homogeneity cytosolic GRBP from rat liver extract and identified it as a Translin/Trax heteromeric complex. Based on partial amino acid sequences, we have cloned full-length rat cDNAs of both Translin and Trax. The nuclear and the cytosolic Translin/Trax complex were both large polymers of 240 and 420 kDa, respectively. The molar ratio of Translin/Trax in the polymers was 2:1 in the liver cytosols. The nuclear and cytosolic Translin/Trax complexes as well as expressed His-tagged Translin bound to double- and single-stranded MLTF sites of the GRE of L-PK gene more avidly than to single-stranded Bcl-CL1, which was initially thought to be specific for Translin. Our findings indicate that the Translin/Trax complex constitutes the previously described GRBP, and that this complex binds the GRE of the L-PK gene with high affinity. The precise physiologic role of GRBP, however, remains unclear.

Animals↗
PubMed2001

Structural characterization of the complex of the Rev response element RNA with a selected peptide.

INTRODUCTION: The RSG-1.2 peptide was selected for specific binding to the Rev response element RNA, as the natural Rev peptide does. The RSG-1.2 sequence has features incompatible with the helical structure of the bound Rev peptide, indicating that it must bind in a different conformation. RESULTS: The binding of the RSG-1.2 peptide to the Rev response element RNA was characterized using multinuclear, multidimensional NMR. The RSG-1.2 peptide is shown to bind with the N-terminal segment of the peptide along the major groove in an extended conformation and turn preceding a C-terminal helical segment, which crosses the RNA groove in the region widened by the presence of purine-purine base pairs. These features make the details of the bound state rather different than that of the Rev peptide which targets the same RNA sequence binding as a single helix along the groove axis. CONCLUSIONS: These studies further demonstrate the versatility of arginine-rich peptides in recognition of specific RNA elements and the lack of conserved structural features in the bound state.

Arginine↗
PubMed2001

A functional retinoic acid response element (RARE) is present within the distal promoter of the rat gonadotropin-releasing hormone (GnRH) gene.

We previously demonstrated that all-trans-retinoic acid (all-trans-RA) regulates gonadotropin-releasing hormone (GnRH) release and gene expression in rat hypothalamic fragments and GT1-1 neuronal cells. Promoter analysis of rat GnRH gene revealed that the enhancing effect of all-trans-RA on GnRH transcription is mediated by cis-elements localized within --1640/--1438 of the rat GnRH promoter. In the present study, we attempted to localize functional retinoic acid response elements (RAREs) within the all-trans-RA-responsive region of the rat GnRH gene. Sequence analysis showed that there exist three putative repeats of AGGTCA-related sequences (--1637/--1617, --1579/--1562, and --1494/--1470) within this promoter sequence. Among them, only the --1494/--1470 sequence could compete the specific binding of GT1-1 nuclear extracts to the consensus RARE (direct repeat of AGGTCA with a 5-bp spacer, DR-5) and vice versa in electrophoretic mobility shift assays. In addition, like consensus RARE, the --1494/--1470 sequence could confer all-trans-RA responsiveness when inserted into the upstream region of SV40 promoter. Treatment of GT1-1 cells with all-trans- or 9-cis-RA increased the specific bindings of GT1-1 nuclear extracts to the consensus RARE and to the --1494/--1470 sequence while not affecting the specific binding to the cAMP response element (CRE). Both retinoids induced RARbeta gene expression in GT1-1 cells. The --1494/--1470 sequence (5'-TCTTAGGACTCTGTGTGACCTAAGA) is similar to the direct repeat of TGACCT (complementary sequence of AGGTCA) with a spacer of 5 bp (i.e. DR-5 in the reverse orientation). A mutation of the second core recognition motif of the --1494/--1470 sequence to a more divergent one from consensus RARE (from TGACCT to TTACAT) abolished the responsiveness to all-trans-RA, whereas a mutation of first core recognition motif to a more TGACCT-like sequence (from AGGACT to TGAACT) increased the responsiveness to all-trans-RA. These results indicate that the --1494/--1470 sequence is indeed a weak but functional RARE of the modified DR-5 type. Taken together, these data indicate that all-trans-RA enhances GnRH transcription via functional RARE present in the distal region of the GnRH promoter.

Animals↗
PubMed2002

Experimentally determined sequence requirement of ACGT-containing abscisic acid response element.

The sequence requirement of the ACGT-containing abscisic acid response element (ABRE) was analyzed by systematically substituting the bases surrounding the ACGT-core of motif A, the principal ABRE of the rice gene, OSEM: This was done within the context of a 55-bp promoter fragment that minimally confers ABA-responsiveness to a heterologous promoter. Based on this analysis, the sequence requirement of the ACGT-containing ABRE was determined as ACGTG G/T C, which matched very well with the consensus derived from sequence comparison of ABA-responsive promoters.

Abscisic Acid↗
PubMed2000

An ordered array of cold shock domain repressor elements across tumor necrosis factor-responsive elements of the granulocyte-macrophage colony-stimulating factor promoter.

The tumor necrosis factor-alpha-responsive region of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) promoter (-114 to -31) encompasses binding sites for NF-kappaB, CBF, AP-1, ETS, and NFAT families of transcription factors. We show both here and previously that mutation of any one of these binding sites greatly reduces tumor necrosis factor-alpha induction of the GM-CSF promoter. Interspersed between these elements are sequences that when mutated lead to an increase in GM-CSF promoter activity. We have previously shown that two of these repressor elements bind proteins known as cold shock domain (CSD) factors and that overexpression of CSD proteins leads to repression of GM-CSF promoter activity in fibroblasts. CSD proteins are single strand DNA- and RNA-binding proteins that contact 5'-CCTG-3' sequences in the GM-CSF repressor elements. We show here that two newly identified repressor sequences in the proximal promoter can also bind CSD proteins. We have characterized the CSD-containing protein complexes that bind to the GM-CSF promoter and identified a novel protein related to mitochondrial single strand binding protein that forms part of one of these complexes. The four CSD-binding sites on the promoter occur in pairs on opposite strands of the DNA and appear to form an ordered array of binding elements. A similar ordered array of CSD sites are present in the promoters of the granulocyte colony-stimulating factor and interleukin-3 genes, implying a common mechanism for negative regulation of these myeloid growth factors.

Base Sequence↗
PubMed1996

Interferon-gamma induction of the human leukocyte antigen-E gene is mediated through binding of a complex containing STAT1alpha to a distinct interferon-gamma-responsive element.

Expression of the human major histocompatibility complex (MHC) class I genes has been shown previously to increase at the transcriptional level following exposure to interferon-gamma (IFN-gamma). In this report we have examined the molecular mechanisms involved in the IFN-gamma-induced transcription of the human MHC class I gene, HLA-E. Functional analysis of CAT reporter gene constructs under the control of the HLA-E promoter transfected into U937 cells revealed the presence of a distinct IFN-gamma-responsive element, termed the interferon response region (IRR), that was necessary and sufficient to mediate the response to IFN-gamma. This cis-acting regulatory sequence contains an imperfect inverted repeat; the 5'-half of the IRR resembles the IFN-gamma activation site (GAS), and the 3'-half of the IRR resembles the interferon-stimulated response element (ISRE). Gel mobility shift assays demonstrated that the IRR bound a single, specific, IFN-gamma-induced complex (IRR-AC), which was formed rapidly following treatment with IFN-gamma and was independent of protein synthesis. Competition experiments with GAS and ISRE sequences from other IFN-inducible genes showed that GAS sequences competed for the IRR-AC, whereas ISRE sequences did not compete. Mutational analysis demonstrated that point mutations in either the 5'-half or 3'-half of the IRR prevented binding of the complex and abrogated or markedly reduced the IFN-gamma responsiveness of reporter gene constructs. Supershift analysis revealed that the IRR-AC contains a factor that was recognized by antibodies specific for the protein STAT1alpha (signal transducer and activator of transcription). Taken together, these findings suggest that the mechanism of IFN-gamma-induced transcription of the HLA-E gene is distinct from that of other MHC class I genes.

Base Sequence↗
PubMed2002

Characterization of a new fatty acid response element that controls the expression of the locust muscle FABP gene.

In vertebrate and invertebrate muscles, the expression of fatty acid binding proteins (FABP) is induced by long chain fatty acids. To identify the fatty acid response elements that mediate this up-regulation, the gene of the FABP expressed in locust flight muscle was cloned, and its upstream sequences analyzed for potential regulatory elements. Comparison with other muscle FABP promoters revealed the presence of a 19-bp imperfect inverted repeat sequence that contains two hexanucleotide half sites (AGTGGT and ATGGGA), interspersed by 3 nucleotides. The promoter activity was studied with reporter gene constructs in L6 myoblasts, in which H-FABP expression is stimulated by long-chain fatty acids in a similar manner as in adult cardiomyocytes. The 19 bp element, located 180 bp upstream of the transcription start site, was found to be essential for the fatty acid induction of gene expression, and gel shift analysis confirmed that this fatty acid response element is capable of binding nuclear proteins both from rat myoblasts and locust muscle in the presence of fatty acids. A similar, but reverse sequence that is present upstream of all mammalian H-FABP promoters may modulate the expression of the rat H-FABP gene.

Animals↗
PubMed2005

Identification of novel cAMP responsive element modulator (CREM) isoforms expressed by osteoblasts.

CREM, the cyclic adenosine monophosphate (cAMP) responsive element modulator, belongs to a multigene family of cAMP-responsive transcription factors. CREM encodes a variety of different isoforms by utilizing four promoters and a complex pattern of alternative messenger ribonucleic acid (mRNA) splicing. We showed previously that parathyroid hormone induces the CREM P2 promoter products known as ICER (inducible cAMP early repressor) in osteoblasts. Herein we report that osteoblasts also express at least 15 CREM transcripts initiated from the P1 promoter, including 7 novel transcripts that result from alternative splicing. It is of interest that we found that CREM-X contains both exon theta1, previously identified only in P3 promoter products, and a new exon termed L, which is located upstream of exon theta1.

3T3 Cells↗
PubMedDate not supplied

Human androgen receptor binding to the androgen response element of prostate specific antigen.

This study examined the in vitro interaction of the human androgen receptor with a putative androgen response element (ARE) in the promoter region of the prostate specific antigen (PSA) gene. To characterize the androgen receptor's interactions with its DNA response elements we expressed the full length human androgen receptor protein in a baculovirus expression system. The receptor was shown to be 110 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and was purified using ion-exchange column chromatography. Binding of the synthetic androgen R1881 to the unpurified recombinant receptor exhibited a kd of 7.6 nM by Scatchard analysis. In DNA gel electromobility shift assays the promoter region from PSA (a 313-bp fragment) was bound by the unpurified recombinant androgen receptor in a sequence-specific manner. An ARE-containing sequence from the promoter region of the PSA gene was synthesized as a 30-bp oligonucleotide and was shown to bind specifically to the human androgen receptor in gel electromobility shift assays by DNA competition and by antibody supershifts of the receptor-ARE complex. The specific binding of the insect cell expressed androgen receptor to its ARE was shown to occur even in the absence of androgen. Androgen receptors purified by ion-exchange chromatography were unable to bind to ARE, suggesting the presence of other factors required for DNA binding.

Animals↗
PubMed1998

Palindrome with spacer of one nucleotide is characteristic of the cis-acting unfolded protein response element in Saccharomyces cerevisiae.

When unfolded proteins are accumulated in the endoplasmic reticulum (ER), an intracellular signaling pathway termed the unfolded protein response (UPR) is activated to induce transcription of ER-localized molecular chaperones and folding enzymes in the nucleus. In Saccharomyces cerevisiae, at least six lumenal proteins including essential Kar2p and Pdi1p are known to be regulated by the UPR. We and others recently demonstrated that the basic-leucine zipper protein Hac1p/Ern4p functions as a trans-acting factor responsible for the UPR. Hac1p binds directly to the cis-acting unfolded protein response element (UPRE) responsible for Kar2p induction. Moreover, we showed that the KAR2 UPRE contains an E box-like palindrome separated by one nucleotide (CAGCGTG) that is essential for its function. We report here that the promoter regions of each of five target proteins (Kar2p, Pdi1p, Eug1p, Fkb2p, and Lhs1p) contain a single UPRE sequence that is necessary and sufficient for induction and that binds specifically to Hac1p in vitro. All of the five functional UPRE sequences identified contain a palindromic sequence that has, in four cases, a spacer of one C nucleotide. This unique characteristic of UPRE explains why only a specific set of proteins are induced in the UPR to cope with ER stress.

Base Sequence↗
PubMed1994

Purification and characterization of a protein that binds to metal responsive elements of the human metallothionein IIA gene.

Metal responsive element (MRE) is a cis-acting DNA motif located in the upstream region of vertebrate metallothionein genes, which can confer metal responsiveness on downstream heterologous promoters. A protein that binds to the MRE sequence in a zinc-dependent manner (zinc regulatory factor; ZRF) was purified 16,000-fold from HeLa cell nuclear extracts by means of the avidin-biotin method, in which a complex formed between ZRF and a biotinylated probe containing MRE was trapped by streptavidin-agarose beads, and ZRF was recovered by salt extraction. By repeating the method three times, a homogeneous 116-kDa protein was obtained whose recovery was zinc-dependent and MRE sequence-specific. UV cross-linking analysis also revealed that a protein that specifically binds to MRE has the same molecular mass as the purified protein. Zinc-dependent and MRE sequence-specific footprints of ZRF were obtained on MREa and MREb in the upstream region of the human metallothionein IIA gene. The ZRF-MRE complex dissociates by the addition of chelating reagents, suggesting a direct role of zinc ions in the DNA binding of ZRF. Partial amino acid sequences of ZRF were found to be highly homologous to those of a mouse MRE-binding protein, mMTF-1.

Amino Acid Sequence↗