Identification of AML-1 and the (8;21) translocation protein (AML-1/ETO) as sequence-specific DNA-binding proteins: the runt homology domain is required for DNA binding and protein-protein interactions

1993 ◽  
Vol 13 (10) ◽  
pp. 6336-6345 ◽  
Author(s):  
S Meyers ◽  
J R Downing ◽  
S W Hiebert

The AML1 gene on chromosome 21 is disrupted in the (8;21)(q22;q22) translocation associated with acute myelogenous leukemia and encodes a protein with a central 118-amino-acid domain with 69% homology to the Drosophila pair-rule gene, runt. We demonstrate that AML-1 is a DNA-binding protein which specifically interacts with a sequence belonging to the group of enhancer core motifs, TGT/cGGT. Electrophoretic mobility shift analysis of cell extracts identified two AML-1-containing protein-DNA complexes whose electrophoretic mobilities were slower than those of complexes formed with AML-1 produced in vitro. Mixing of in vitro-produced AML-1 with cell extracts prior to gel mobility shift analysis resulted in the formation of higher-order complexes. Deletion mutagenesis of AML-1 revealed that the runt homology domain mediates both sequence-specific DNA binding and protein-protein interactions. The hybrid product, AML-1/ETO, which results from the (8;21) translocation and retains the runt homology domain, both recognizes the AML-1 consensus sequence and interacts with other cellular proteins.

1993 ◽  
Vol 13 (10) ◽  
pp. 6336-6345 ◽  
Author(s):  
S Meyers ◽  
J R Downing ◽  
S W Hiebert

The AML1 gene on chromosome 21 is disrupted in the (8;21)(q22;q22) translocation associated with acute myelogenous leukemia and encodes a protein with a central 118-amino-acid domain with 69% homology to the Drosophila pair-rule gene, runt. We demonstrate that AML-1 is a DNA-binding protein which specifically interacts with a sequence belonging to the group of enhancer core motifs, TGT/cGGT. Electrophoretic mobility shift analysis of cell extracts identified two AML-1-containing protein-DNA complexes whose electrophoretic mobilities were slower than those of complexes formed with AML-1 produced in vitro. Mixing of in vitro-produced AML-1 with cell extracts prior to gel mobility shift analysis resulted in the formation of higher-order complexes. Deletion mutagenesis of AML-1 revealed that the runt homology domain mediates both sequence-specific DNA binding and protein-protein interactions. The hybrid product, AML-1/ETO, which results from the (8;21) translocation and retains the runt homology domain, both recognizes the AML-1 consensus sequence and interacts with other cellular proteins.


2020 ◽  
Author(s):  
Ken-ichi Yoshida ◽  
Yusuke Shirae ◽  
Ryo Nishimura ◽  
Kaho Fukui ◽  
Shu Ishikawa

Abstract BackgroundGeobacillus kaustophilus HTA426, a thermophilic Gram-positive bacterium, grows on inositol as its sole carbon source, and an iol gene cluster required for inositol catabolism has been postulated with reference to the iol genes in Bacillus subtilis. The iol gene cluster consists of two tandem operons induced in the presence of inositol; however, the mechanism underlying the induction remains unclear. B. subtilis iolQ is known to be involved in the regulation of iolX encoding a scyllo-inositol dehydrogenase, and its homolog in HTA426 was found two genes upstream of the first gene (gk1899) of the iol gene cluster and termed as iolQ in G. kaustophilus.ResultsWhen iolQ was inactivated, not only the myo-inositol dehydrogenase activity in the cell due to the expression of gk1899 but also the transcription of the two iol operons became constitutive. IolQ was produced and purified as a C-terminal His-tag fusion in Escherichia coli and subjected to the in vitro gel mobility shift assay to examine its DNA binding property. It was observed that IolQ bound to the DNA fragments containing each of the two iol promoter regions, and its DNA binding was antagonized by myo-inositol. Moreover, DNase I footprint analyses were conducted to determine the two binding sites of IolQ within each of the iol promoter regions. By comparing the sequences of the binding sites, a consensus sequence for IolQ binding was deduced to be a palindrome of 5′-RGWAAGCGCTTSCY-3′ (where R = A or G, W = A or T, S = G or C, and Y = C or T).ConclusionIolQ functions as a transcriptional repressor regulating the induction of the two iol operons responding to myo-inositol.


1999 ◽  
Vol 19 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Min-Yuan Chou ◽  
Nanette Rooke ◽  
Christoph W. Turck ◽  
Douglas L. Black

ABSTRACT The regulation of the c-src N1 exon is mediated by an intronic splicing enhancer downstream of the N1 5′ splice site. Previous experiments showed that a set of proteins assembles onto the most conserved core of this enhancer sequence specifically in neuronal WERI-1 cell extracts. The most prominent components of this enhancer complex are the proteins hnRNP F, KSRP, and an unidentified protein of 58 kDa (p58). This p58 protein was purified from the WERI-1 cell nuclear extract by ammonium sulfate precipitation, Mono Q chromatography, and immunoprecipitation with anti-Sm antibody Y12. Peptide sequence analysis of purified p58 protein identified it as hnRNP H. Immunoprecipitation of hnRNP H cross-linked to the N1 enhancer RNA, as well as gel mobility shift analysis of the enhancer complex in the presence of hnRNP H-specific antibodies, confirmed that hnRNP H is a protein component of the splicing enhancer complex. Immunoprecipitation of splicing intermediates from in vitro splicing reactions with anti-hnRNP H antibody indicated that hnRNP H remains bound to the src pre-mRNA after the assembly of spliceosome. Partial immunodepletion of hnRNP H from the nuclear extract partially inactivated the splicing of the N1 exon in vitro. This inhibition of splicing can be restored by the addition of recombinant hnRNP H, indicating that hnRNP H is an important factor for N1 splicing. Finally, in vitro binding assays demonstrate that hnRNP H can interact with the related protein hnRNP F, suggesting that hnRNPs H and F may exist as a heterodimer in a single enhancer complex. These two proteins presumably cooperate with each other and with other enhancer complex proteins to direct splicing to the N1 exon upstream.


2005 ◽  
Vol 25 (20) ◽  
pp. 8864-8873 ◽  
Author(s):  
Nibedita Rath ◽  
Zhishan Wang ◽  
Min Min Lu ◽  
Edward E. Morrisey

ABSTRACT The activity of GATA factors is regulated, in part, at the level of protein-protein interactions. LIM domain proteins, first defined by the zinc finger motifs found in the Lin11, Isl-1, and Mec-3 proteins, act as coactivators of GATA function in both hematopoietic and cardiovascular tissues. We have identified a novel GATA-LIM interaction between GATA6 and LMCD1/dyxin. The LIM domains and cysteine-rich domains in LMCD1/dyxin and the carboxy-terminal zinc finger of GATA6 mediate this interaction. Expression of LMCD1/dyxin is remarkably similar to that of GATA6, with high-level expression observed in distal airway epithelium of the lung, vascular smooth muscle, and myocardium. In contrast to other GATA-LIM protein interactions, LMCD1/dyxin represses GATA6 activation of both lung and cardiac tissue-specific promoters. Electrophoretic mobility shift and chromatin immunoprecipitation assays show that LMCD1/dyxin represses GATA6 function by inhibiting GATA6 DNA binding. These data reveal an interaction between GATA6 and LMCD1/dyxin and demonstrate a novel mechanism through which LIM proteins can assert their role as transcriptional cofactors of GATA proteins.


1995 ◽  
Vol 131 (2) ◽  
pp. 311-324 ◽  
Author(s):  
P Espenshade ◽  
R E Gimeno ◽  
E Holzmacher ◽  
P Teung ◽  
C A Kaiser

Temperature-sensitive mutations in the SEC16 gene of Saccharomyces cerevisiae block budding of transport vesicles from the ER. SEC16 was cloned by complementation of the sec16-1 mutation and encodes a 240-kD protein located in the insoluble, particulate component of cell lysates. Sec16p is released from this particulate fraction by high salt, but not by nonionic detergents or urea. Some Sec16p is localized to the ER by immunofluorescence microscopy. Membrane-associated Sec16p is incorporated into transport vesicles derived from the ER that are formed in an in vitro vesicle budding reaction. Sec16p binds to Sec23p, a COPII vesicle coat protein, as shown by the two-hybrid interaction assay and affinity studies in cell extracts. These findings indicate that Sec16p associates with Sec23p as part of the transport vesicle coat structure. Genetic analysis of SEC16 identifies three functionally distinguishable domains. One domain is defined by the five temperature-sensitive mutations clustered in the middle of SEC16. Each of these mutations can be complemented by the central domain of SEC16 expressed alone. The stoichiometry of Sec16p is critical for secretory function since overexpression of Sec16p causes a lethal secretion defect. This lethal function maps to the NH2-terminus of the protein, defining a second functional domain. A separate function for the COOH-terminal domain of Sec16p is shown by its ability to bind Sec23p. Together, these results suggest that Sec16p engages in multiple protein-protein interactions both on the ER membrane and as part of the coat of a completed vesicle.


1993 ◽  
Vol 13 (2) ◽  
pp. 1069-1077 ◽  
Author(s):  
J Sidorova ◽  
L Breeden

SWI4 and SWI6 play a crucial role in START-specific transcription in Saccharomyces cerevisiae. SWI4 and SWI6 form a specific complex on the SCB (SWI4/6-dependent cell cycle box) sequences which have been found in the promoters of HO and G1 cyclin genes. Overproduction of SWI4 eliminates the SWI6 dependency of HO transcription in vivo and results in a new SWI6-independent, SCB-specific complex in vitro, which is heterogeneous and reacts with SWI4 antibodies. The C terminus of SWI4 is not required for SWI6-independent binding of SWI4 to SCB sequences, but it is necessary and sufficient for association with SWI6. Both SWI4 and SWI6 contain two copies of a 33-amino-acid TPLH repeat, which has been implicated in protein-protein interactions in other proteins. These repeats are not required for the SWI4-SWI6 association. Alanine substitutions in both TPLH repeats of SWI6 reduce its activity but do not affect the stability of the protein or its association with SWI4. However, these mutations reduce the ability of the SWI4/6 complex to bind DNA. Deletion of the lucine zipper motif in SWI6 also allows SWI4/6 complex formation, but it eliminates the DNA-binding ability of the SWI4/6 complex. This indicates that the integrity of two different regions of SWI6 is required for DNA binding by the SWI4/6 complex. From these data, we propose that the sequence-specific DNA-binding domain resides in SWI4 but that SWI6 controls the accessibility of this domain in the SWI4/6 complex.


2015 ◽  
Vol 35 (19) ◽  
pp. 3284-3300 ◽  
Author(s):  
Tiancen Hu ◽  
Jennifer E. Yeh ◽  
Luca Pinello ◽  
Jaison Jacob ◽  
Srinivas Chakravarthy ◽  
...  

The transcription factor STAT3 is constitutively active in many cancers, where it mediates important biological effects, including cell proliferation, differentiation, survival, and angiogenesis. The N-terminal domain (NTD) of STAT3 performs multiple functions, such as cooperative DNA binding, nuclear translocation, and protein-protein interactions. However, it is unclear which subsets of STAT3 target genes depend on the NTD for transcriptional regulation. To identify such genes, we compared gene expression inSTAT3-null mouse embryonic fibroblasts (MEFs) stably expressing wild-type STAT3 or STAT3 from which NTD was deleted. NTD deletion reduced the cytokine-induced expression of specific STAT3 target genes by decreasing STAT3 binding to their regulatory regions. To better understand the potential mechanisms of this effect, we determined the crystal structure of the STAT3 NTD and identified a dimer interface responsible for cooperative DNA bindingin vitro. We also observed an Ni2+-mediated oligomer with an as yet unknown biological function. Mutations on both dimer and Ni2+-mediated interfaces affected the cytokine induction of STAT3 target genes. These studies shed light on the role of the NTD in transcriptional regulation by STAT3 and provide a structural template with which to design STAT3 NTD inhibitors with potential therapeutic value.


1999 ◽  
Vol 19 (4) ◽  
pp. 2577-2584 ◽  
Author(s):  
Elzbieta Biesiada ◽  
Yasuo Hamamori ◽  
Larry Kedes ◽  
Vittorio Sartorelli

ABSTRACT Activation of the human cardiac α-actin (HCA) promoter in skeletal muscle cells requires the integrity of DNA binding sites for the serum response factor (SRF), Sp1, and the myogenic basic helix-loop-helix (bHLH) family. In this study we report that activation of the HCA correlates with formation of a muscle-specific multiprotein complex on the promoter. We provide evidence that proteins eluted from the multiprotein complex specifically react with antibodies directed against myogenin, Sp1, and SRF and that the complex can be assembled in vitro by using the HCA promoter and purified MyoD, E12, SRF, and Sp1. In vitro and in vivo assays revealed a direct association of Sp1 and myogenin-MyoD mediated by the DNA-binding domain of Sp1 and the HLH motif of myogenin. The results obtained in this study indicate that protein-protein interactions and the cooperative DNA binding of transcriptional activators are critical steps in the formation of a transcriptionally productive multiprotein complex on the HCA promoter and suggest that the same mechanisms might be utilized to regulate the transcription of muscle-specific and other genes.


Genes ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 684 ◽  
Author(s):  
Guangzhe Yang ◽  
Dong Chao ◽  
Zhenhua Ming ◽  
Jixing Xia

Binding of transcription factors (TFs) to cis-regulatory elements (DNA) could modulate the expression of downstream genes, while interactions between TFs and other proteins might inhibit them binding to DNA. Nowadays, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) approaches are usually employed to detect the inhibitory effect. However, EMSA might not reflect the inhibitory effect in vivo. ChIP requires preparation of specific antibody or stable genetic transformation and complicated experimental steps, making it laborious and time-consuming. Here, based on the yeast one-hybrid (Y1H) system, we present a simple method to detect the inhibition of TF–DNA binding due to protein–protein interactions in vivo. When interactions between TFs and other proteins inhibit TFs binding to DNA, the reporter (Aureobasidin A resistance) gene is not activated, thereby inhibiting yeast growth on media containing the AbA antibiotic. Two examples were tested with the newly developed method to demonstrate its feasibility. In conclusion, this method provides an alternative strategy for detecting the inhibition of DNA-binding of TFs due to their interactions with other proteins in vivo.


1995 ◽  
Vol 15 (3) ◽  
pp. 1602-1612 ◽  
Author(s):  
K Kitagawa ◽  
H Masumoto ◽  
M Ikeda ◽  
T Okazaki

We previously reported that centromere protein B (CENP-B) forms a stable complex (designated complex A) containing two alphoid DNAs in vitro. Domains in the CENP-B polypeptide involved in the formation of complex A were determined in the present study with truncated derivatives expressed in Escherichia coli and in rabbit reticulocyte lysates. It was revealed by gel mobility shift analyses that polypeptides containing the NH2-terminal DNA-binding domain bind a DNA molecule as a monomer, while dimerizing at a novel hydrophobic domain in the COOH-terminal region of 59 amino acid residues. This polypeptide dimerization activity at the COOH-terminal region was also confirmed with the two-hybrid system in Saccharomyces cerevisiae cells. The results thus proved that CENP-B polypeptides form a homodimer at the COOH-terminal hydrophobic domain, each binding a DNA strand at their NH2-terminal domains. The dimerization and DNA-binding domains fall into two of the three completely conserved sequences found in human and mouse CENP-B, and complex A-forming activity was also detected in nuclear extracts of mouse cells. Metaphase-specific phosphorylation of CENP-B was also detected, but this had no effect on its complex A-forming activity. On the basis of the present results, we propose that CENP-B plays an important role in the assembly of specific centromere structures by forming unique DNA-protein complexes at the sites of CENP-B boxes on the centromeric repetitive DNA both in interphase nuclei and on mitotic chromosomes.


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