Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An increasing number of independent studies indicate that the atypical protein kinase C (PKC) isoforms (aPKCs) are critically involved in the control of cell proliferation and survival. The aPKCs are targets of important lipid mediators such as ceramide and the products of the PI 3-kinase. In addition, the aPKCs have been shown to interact with Ras and with two novel proteins, LIP (lambda-interacting protein; a selective activator of lambda/iotaPKC) and the product of par-4 (a gene induced during apoptosis), which is an inhibitor of both lambda/iotaPKC and zetaPKC. LIP and Par-4 interact with the zinc finger domain of the aPKCs where the lipid mediators have been shown to bind. Here we report the identification of p62, a previously described phosphotyrosine-independent p56(lck) SH2-interacting protein, as a molecule that interacts potently with the V1 domain of lambda/iotaPKC and, albeit with lower affinity, with zetaPKC. We also show in this study that ectopically expressed p62 colocalizes perfectly with both lambda/iotaPKC and zetaPKC. Interestingly, the endogenous p62, like the ectopically expressed protein, displays a punctate vesicular pattern and clearly colocalizes with endogenous lambda/iotaPKC and endogenous zetaPKC. P62 colocalizes with Rab7 and partially with lamp-1 and limp-II as well as with the epidermal growth factor (EGF) receptor in activated cells, but not with Rab5 or the transferrin receptor. Of functional relevance, expression of dominant negative lambda/iotaPKC, but not of the wild-type enzyme, severely impairs the endocytic membrane transport of the EGF receptor with no effect on the transferrin receptor. These findings strongly suggest that the aPKCs are anchored by p62 in the lysosome-targeted endosomal compartment, which seems critical for the control of the growth factor receptor trafficking. This is particularly relevant in light of the role played by the aPKCs in mitogenic cell signaling events.
 ...
PMID:Localization of atypical protein kinase C isoforms into lysosome-targeted endosomes through interaction with p62. 956 25

To create a universal system for the control of gene expression, we have studied methods for the construction of novel polydactyl zinc finger proteins that recognize extended DNA sequences. Elsewhere we have described the generation of zinc finger domains recognizing sequences of the 5'-GNN-3' subset of a 64-member zinc finger alphabet. Here we report on the use of these domains as modular building blocks for the construction of polydactyl proteins specifically recognizing 9- or 18-bp sequences. A rapid PCR assembly method was developed that, together with this predefined set of zinc finger domains, provides ready access to 17 million novel proteins that bind the 5'-(GNN)6-3' family of 18-bp DNA sites. To examine the efficacy of this strategy in gene control, the human erbB-2 gene was chosen as a model. A polydactyl protein specifically recognizing an 18-bp sequence in the 5'-untranslated region of this gene was converted into a transcriptional repressor by fusion with Kr uppel-associated box (KRAB), ERD, or SID repressor domains. Transcriptional activators were generated by fusion with the herpes simplex VP16 activation domain or with a tetrameric repeat of VP16's minimal activation domain, termed VP64. We demonstrate that both gene repression and activation can be achieved by targeting designed proteins to a single site within the transcribed region of a gene. We anticipate that gene-specific transcriptional regulators of the type described here will find diverse applications in gene therapy, functional genomics, and the generation of transgenic organisms.
 ...
PMID:Toward controlling gene expression at will: specific regulation of the erbB-2/HER-2 promoter by using polydactyl zinc finger proteins constructed from modular building blocks. 984 40

Gene regulation by imposed localization was studied by using designed zinc finger proteins that bind 18-bp DNA sequences in the 5' untranslated regions of the protooncogenes erbB-2 and erbB-3. Transcription factors were generated by fusion of the DNA-binding proteins to repression or activation domains. When introduced into cells these transcription factors acted as dominant repressors or activators of, respectively, endogenous erbB-2 or erbB-3 gene expression. Significantly, imposed regulation of the two genes was highly specific, despite the fact that the transcription factor binding sites targeted in erbB-2 and erbB-3 share 15 of 18 nucleotides. Regulation of erbB-2 gene expression was observed in cells derived from several species that conserve the DNA target sequence. Repression of erbB-2 in SKBR3 breast cancer cells inhibited cell-cycle progression by inducing a G(1) accumulation, suggesting the potential of designed transcription factors for cancer gene therapy. These results demonstrate the willful up- and down-regulation of endogenous genes, and provide an additional means to alter biological systems.
 ...
PMID:Positive and negative regulation of endogenous genes by designed transcription factors. 1066 Jun 90

In previous studies we have developed Cys(2)-His(2) zinc finger domains that specifically recognized each of the 16 5'-GNN-3' DNA target sequences and could be used to assemble six-finger proteins that bind 18-base pair DNA sequences (Beerli, R. R., Dreier, B., and Barbas, C. F., III (2000) Proc. Natl. Acad. Sci. U. S. A. 97, 1495--1500). Such proteins provide the basis for the construction of artificial transcription factors to study gene/function relationships in the post-genomic era. Central to the universal application of this approach is the development of zinc finger domains that specifically recognize each of the 64 possible DNA triplets. Here we describe the construction of a novel phage display library that enables the selection of zinc finger domains recognizing the 5'-ANN-3' family of DNA sequences. Library selections provided domains that in most cases showed binding specificity for the 3-base pair target site that they were selected to bind. These zinc finger domains were used to construct 6-finger proteins that specifically bound their 18-base pair target site with affinities in the pm to low nm range. When fused to regulatory domains, these proteins containing various numbers of 5'-ANN-3' domains were capable of specific transcriptional regulation of a reporter gene and the endogenous human ERBB-2 and ERBB-3 genes. These results suggest that modular DNA recognition by zinc finger domains is not limited to the 5'-GNN-3' family of DNA sequences and can be extended to the 5'-ANN-3' family. The domains characterized in this work provide for the rapid construction of artificial transcription factors, thereby greatly increasing the number of sequences and genes that can be targeted by DNA-binding proteins built from pre-defined zinc finger domains.
 ...
PMID:Development of zinc finger domains for recognition of the 5'-ANN-3' family of DNA sequences and their use in the construction of artificial transcription factors. 1134 73

Considerable progress has been made in recent years in the design of transcription factors for the directed regulation of endogenous genes. Although many strategies involve selection methods that must be applied for each new target sequence, we have developed an approach based on linkage of predefined zinc finger domains that each recognize a three-base pair DNA sequence to construct artificial transcription factors that bind to a desired sequence. These domains can be assembled to recognize unique 18-base pair DNA sequences with high specificity. Here we report the development and characterization of zinc finger domains that bind to 15 of the 16 5'-CNN-3' subsites. These domains were created through a combination of phage display selection, site-directed mutagenesis, and de novo design. Furthermore, these domains were used to generate a highly specific six-finger protein targeting the ERBB-2 promoter. When fused to regulatory domains, this protein was capable of up- and down-regulating the expression of the endogenous ERBB-2 gene. With the addition of this collection of predefined zinc finger domains, most 5'-CNN-3'-, 5'-GNN-3'-, and 5'-ANN-3'-containing sequences can now be rapidly targeted for directed gene regulation and nuclease cleavage.
 ...
PMID:Development of zinc finger domains for recognition of the 5'-CNN-3' family DNA sequences and their use in the construction of artificial transcription factors. 1610 35

The Sleeping Beauty (SB) transposon is a nonviral, integrating vector system with proven efficacy in preclinical animal models, and thus holds promise for future clinical applications. However, SB has a close-to-random insertion profile that could lead to genotoxic effects, thereby presenting a potential safety issue. We evaluated zinc finger (ZF) DNA-binding domains (DBDs) for their abilities to introduce a bias into SB's insertion profile. E2C, that binds a unique site in the erbB-2 gene, mediated locus-specific transposon insertions at low frequencies. A novel ZF targeting LINE1 repeats, ZF-B, showed specific binding to an 18-bp site represented by ~12,000 copies in the human genome. We mapped SB insertions using linear-amplification (LAM)-PCR and Illumina sequencing. Targeted insertions with ZF-B peaked at approximately fourfold enrichment of transposition around ZF-B binding sites yielding ~45% overall frequency of insertion into LINE1. A decrease in the ZF-B dataset with respect to transposon insertions in genes was found, suggesting that LINE1 repeats act as a sponge that "soak up" a fraction of SB insertions and thereby redirect them away from genes. Improvements in ZF technology and a careful choice of targeted genomic regions may improve the safety profile of SB for future clinical applications.
 ...
PMID:Retargeting sleeping beauty transposon insertions by engineered zinc finger DNA-binding domains. 2277 59