Structure-Function Analysis of Bag1 Proteins

Knee, Deborah; Froesch, Barbara A.; Nuber, Ulrike A.; Takayama, Shinichi; Reed, John C.

doi:10.1074/jbc.m010841200

Cited by 63 publications

(37 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, we propose that the additional N-terminal amino acids of BAG-1L are necessary only for those receptors that do not promote nuclear transport of BAG-1M. This is also supported by the observation that BAG-1M is effective on vitamin D receptor upon forced nuclear targeting (9). We discovered that the N-terminal 8 amino acids of BAG-1M, which probably represent the entire DNA binding domain, are also required for its function on GR.…”

Section: The Dna Binding and The Hsp70 Interaction Domain Of Bag-1 Nesupporting

confidence: 59%

“…In the case of the androgen receptor BAG-1 enhances transcription, but the domains required are similar at first sight, because the N-terminal domain of the long isoform BAG-1L and the hsp70 interaction domain are both required (9). However, it appears that the N-terminal domain of BAG-1L is necessary only for nuclear targeting, because BAG-1M is inefficient unless it is forced to the nucleus by adding a targeting sequence (9). Similarly, the vitamin D receptor also has been reported to be enhanced by BAG-1L but not by BAG-1M.…”

Section: The Dna Binding and The Hsp70 Interaction Domain Of Bag-1 Nementioning

confidence: 99%

“…It also is termed "hap46," hsp70-and hsc70-associating protein (7). BAG-1 enhances the transcriptional activity of the androgen receptor (8,9), and in the case of the vitamin D receptor evidence has been provided for both enhancement (10) and inhibition (11) of transcriptional activity. In addition, BAG-1 interaction with the retinoic acid receptor (RAR) results in inhibition of binding of RAR to its response elements on DNA and of RAR-dependent transcription (12).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Essential Role of the Unusual DNA-binding Motif of BAG-1 for Inhibition of the Glucocorticoid Receptor

Schmidt¹,

Wochnik²,

Rosenhagen³

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

The co-chaperone BAG-1 is involved in the regulation of steroid hormone receptors, including the glucocorticoid receptor (GR). More recently, BAG-1 was found in the nucleus where it decreases GR transactivation. Moreover, nonspecific DNA binding of BAG-1 has been reported. We discovered that of the N-terminal part of BAG-1M, the first 8 amino acids are sufficient for DNA binding, containing a stretch of three lysines and a stretch of three arginines. Changing the spacing between these stretches had no effect on DNA binding. Surprisingly, this small, nonsequence-specific DNA binding domain was nonetheless necessary for the inhibitory function of BAG-1 for GR-dependent transcription, whereas the following serine-and threonine-rich E 2 X 4 repeat domain was not. Mutational analysis of these two domains revealed that only mutants retaining DNA binding capability were able to down-regulate GRmediated transactivation. Intriguingly, lack of DNA binding could not be functionally rescued by BAG-1M harboring a point mutation abolishing interaction with hsp70. Thus, DNA binding and hsp70 interaction are required in cis. We propose that the nonsequence-specific DNA-binding protein BAG-1 acts at specific chromosomal loci by interacting with other proteins.

show abstract

Section: The Dna Binding and The Hsp70 Interaction Domain Of Bag-1 Nesupporting

confidence: 59%

Section: The Dna Binding and The Hsp70 Interaction Domain Of Bag-1 Nementioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Essential Role of the Unusual DNA-binding Motif of BAG-1 for Inhibition of the Glucocorticoid Receptor

Schmidt¹,

Wochnik²,

Rosenhagen³

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…The cDNAs encoding various fragments of DEDD2 were generated by PCR from the plasmid pcDNA3-DEDD2 using the following forward (F) and reverse (R) primers containing EcoRI and XhoI restriction sites and the sequence encoding the FLAG epitope tag: N1-DEDD2, 5Ј-CGGAATTCACCATGGACTACAAAGACGATGACGAC-AAGGCGCTATCCGGGTCGACC-3Ј (F) and 5Ј-CCGCTCGAGTCAGT-GCGGCAGCAGGTCGT-3Ј (R); N2-DEDD2, 5Ј-CGGAATTCACCATGG-ACTACAAAGACGATGACGACAAGGCGCTATCCGGGTCGACC-3Ј (F) and 5Ј-CCGCTCGAGTCAGCGACGGCAGCTACCCTC-3Ј (R); N3-DEDD2, 5Ј-CGGAATTCACCATGGACTACAAAGACGATGACGACAA-GGCGCTATCCGGGTCGACC-3Ј (F) and 5Ј-CCGCTCGAGTCATGGC-CCATGCTCGCAGTA-3Ј (R); C1-DEDD2, 5Ј-CCGGAATTCACCATGG-CACCCCAGCAGCAGTCA-3Ј (F) and 5Ј-CCGCTCGAGTCACTTGTCG-TCATCGTCTTTGTAGTCGGAGGCCTCTGTCGGGCG-3Ј (R); C2-DEDD2, 5Ј-CCGGAATTCACCATGGAGGGTAGCTGCCGTCGC-3Ј (F) and 5Ј-CCGCTCGAGTCACTTGTCGTCATCGTCTTTGTAGTCGGAG-GCCTCTGTCGGGCG-3Ј (R). To generate the nuclear-targeted DEDD2 proteins, various DEDD2 fragments were subcloned into the EcoRI and XhoI sites of pcDNA3-NLS (generated by the insertion of an oligonucleotide encoding for the SV40-LargeT-like nuclear localization signal into the HindIII-EcoRI sites of pcDNA3.1) (14).…”

Section: Northern Blotting and Rt-pcr Analysis-northern Blot Membranementioning

confidence: 99%

Identification and Characterization of DEDD2, a Death Effector Domain-containing Protein

Roth

Stenner

Pawłowski

et al. 2002

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

A novel Death Effector Domain-containing protein was identified, DEDD2, which is closest in amino acid sequence homology to death effector domain-containing DNA-binding protein, DEDD. DEDD2 mRNA is expressed widely in adult human tissues with highest levels in liver, kidney, and peripheral blood leukocytes. DEDD2 interacts with FLIP, but not with Fas-associated death domain (FADD) or caspase-8. Overexpression of DEDD2 induces moderate apoptosis and results in substantial sensitization to apoptosis induced by Fas (CD95/ APO-1), tumor necrosis factor-related apoptosis-inducing ligand (TRAIL, Apo2L), or FADD. In contrast, Bax-or staurosporine-mediated cell death is not affected by expression of DEDD2. Fluorescence microscopy showed that overexpressed DEDD2 translocates to the nucleus, which is dependent on the presence of a bipartite nuclear localization signal in the DEDD2 protein. Mutagenesis studies revealed that the translocation of the DED of DEDD2 to the nucleus is essential for its proapoptotic activity. These findings suggest that DEDD2 is involved in the regulation of nuclear events mediated by the extrinsic apoptosis pathway.The initiation of death receptor-mediated apoptosis is characterized by the formation of signaling complexes that involve proteins containing the Death Domain (DD) 1 and Death Effector Domain (DED). Upon activation of death receptors such as Fas, the cytoplasmic adaptor molecule FADD interacts with the intracellular regions of the receptor proteins by homotypic binding of their DDs (1). Transduction of the apoptotic signal then depends on interaction of the DED in FADD with corresponding DEDs in pro-caspase-8, or pro-caspase-10, resulting in a protein complex that promotes trans-proteolysis of receptor-associated caspase pro-enzymes (2). The association of Fas (CD95/APO-1), FADD, and pro-caspase-8 has been termed "death-inducing signaling complex" (DISC) (3). The active caspase subunits are then released into the cytosol, where they cleave various substrates, including other caspases (e.g. caspase-3 (4)), cytoskeletal proteins (e.g. plectin (5)), or apoptosis effectors such as Bid (6, 7). Finally, the late stages of apoptosis are characterized by DNA fragmentation, which can be accomplished by endonucleases, such as caspase-activated DNase (8), and nuclear fragmentation associated with cleavage of nuclear scaffold proteins such as lamin (9).Besides the crucial role of DED proteins in the formation of the DISC and the activation of DED-containing initiator caspases, DEDs in viral or cellular proteins also have the ability to inhibit apoptosis. The proteins v-FLIP and c-FLIP (FLICE-inhibitory proteins) bind to the DEDs of pro-caspase-8 and -10, interfering with their activation in the DISC (10). This DED-mediated anti-apoptotic mechanism may be of particular importance, because overexpression of FLIP has been reported in several types of cancer (11,12).However, DED-containing proteins affect apoptotic signaling in addition to interfering with initial events of apoptosis, such as the DIS...

show abstract

“…BAG-1 isoforms are generated by alternate translation initiation of a single mRNA (Packham et al, 1997;Takayama et al, 1998;Yang et al, 1998;Coldwell et al, 2001) and therefore share a common C-terminus with the larger isoforms having additional N-terminal sequences. The unique N-terminus of BAG-1L contains a nuclear localization sequence and is predominantly located within the nucleus, whereas BAG-1S is predominantly a cytoplasmic protein and BAG-1M partitions between the nucleus and cytoplasm (Packham et al, 1997;Takayama et al, 1998;Yang et al, 1998;Brimmell et al, 1999;Knee et al, 2001).…”

Section: Introductionmentioning

confidence: 99%