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Ahmed CM, Wills KN, Sugarman BJ, Johnson DE, Ramachandra M, Nagabhushan TL, Howe JA. Selective expression of nonsecreted interferon by an adenoviral vector confers antiproliferative and antiviral properties and causes reduction of tumor growth in nude mice. J Interferon Cytokine Res 2001; 21:399-408. [PMID: 11440637 DOI: 10.1089/107999001750277871] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Replication-deficient adenoviruses expressing human interferon-alpha2b (HuIFN-alpha2b) or the hybrid IFN-alpha2alpha1 or those with the secretory signal deleted, whose express is driven by the alpha-fetoprotein (AFP) promoter, were constructed and characterized. Synthesis of IFN protein and secretion or intracellular retention were tested by Western blotting and immunoassay. Expression of IFN by the recombinant adenoviruses was restricted to cells that constitutively express AFP. In these cells, expression of both secreted and nonsecreted recombinant IFN resulted in inhibition of cell proliferation, resistance to viral infection, induction of major histocompatibility complex (MHC) class I expression, increased apoptosis, and activation of an IFN-stimulated response element (ISRE)-containing promoter. Also, the induction of protein kinase R (PKR), increased phosphorylation of Stat1, and accumulation of hypophosphorylated pRb were observed for both the secreted and nonsecreted IFN, suggesting that the nonsecreted IFN may act through a similar pathway. Hep3B cells, an AFP-positive line derived from a patient with hepatocellular carcinoma (HCC), were injected subcutaneously (s.c.) into athymic nude mice to generate established tumors. Intratumoral injection of recombinant adenoviruses expressing secreted as well as the nonsecreted IFN caused suppression of tumor growth. As the AFP promoter is activated in many HCC cells but is silent in normal cells, these constructs may be useful in restricting IFN effects to the tumor cells while reducing toxicity to the neighboring tissues.
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Fattman CL, Delach SM, Dou QP, Johnson DE. Sequential two-step cleavage of the retinoblastoma protein by caspase-3/-7 during etoposide-induced apoptosis. Oncogene 2001; 20:2918-26. [PMID: 11420704 DOI: 10.1038/sj.onc.1204414] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2000] [Revised: 02/14/2001] [Accepted: 02/21/2001] [Indexed: 12/24/2022]
Abstract
During cellular apoptosis, retinoblastoma protein (RB) is subjected to cleavage near the carboxyl terminus by a caspase-3-like protease. In addition, an heretofore unidentified protease cleaves RB internally, generating fragments of 68 and 48 kDa. Internal cleavage abrogates the ability of RB to associate with E2F. To investigate the mechanism of RB internal cleavage, we developed and employed an in vitro cleavage assay. Incubation of in vitro translated (35)S-RB with apoptotic cell extracts led to RB cleavage at the C-terminus, followed by internal cleavage. The caspase peptide inhibitors z-VAD-FMK or z-DEVD-FMK blocked both cleavage events. Rapid C-terminal and internal cleavage were also observed when recombinant caspase-3 was added to (35)S-RB. Moreover, when caspase-3 was added to nonapoptotic cell extract, efficient internal cleavage of cellular RB was observed. Caspase-mediated internal cleavage occurred following RB residue aspartate(349) in the sequence DSID(349). This sequence is consistent with a DXXD recognition motif for caspase-3-like enzymes. Interestingly, we also observed RB internal cleavage in caspase-3-deficient MCF-7 cells, indicating that other caspases are capable of cleaving RB internally. Indeed, caspase-7, a member of the caspase-3 subfamily, was found to cleave (35)S-RB at both the carboxyl terminus, and following aspartate(349). By contrast, caspases that are not members of the caspase-3 subfamily failed to cleave RB. Taken together, our findings demonstrate that during apoptosis, a caspase-3-like protease is responsible for degradation and functional inactivation of RB by cleaving the protein internally following aspartate(349).
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Gunther NW, Lockatell V, Johnson DE, Mobley HL. In vivo dynamics of type 1 fimbria regulation in uropathogenic Escherichia coli during experimental urinary tract infection. Infect Immun 2001; 69:2838-46. [PMID: 11292696 PMCID: PMC98232 DOI: 10.1128/iai.69.5.2838-2846.2001] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Escherichia coli is the primary cause of uncomplicated infections of the urinary tract including cystitis. More serious infections, characterized as acute pyelonephritis, can also develop. Type 1 fimbriae of E. coli contribute to virulence in the urinary tract; however, only recently has the expression of the type 1 fimbriae been investigated in vivo using molecular techniques. Transcription of type 1 fimbrial genes is controlled by a promoter that resides on a 314-bp invertible element capable of two orientations. One places the promoter in the ON orientation, allowing for transcription; the other places the promoter in the OFF orientation, preventing transcription. A PCR-based assay was developed to measure the orientation of the invertible element during an experimental urinary tract infection in mice. Using this assay, it was found that the percentage of the population ON in urine samples correlated with the respective CFU per gram of bladder (P = 0.0006) but not with CFU per gram of kidney (P > 0.069). Cystitis isolates present in the urine of mice during the course of infection had a higher percentage of their invertible elements in the ON orientation than did pyelonephritis isolates (85 and 34%, respectively, at 24 h; P < 0.0001). In general, cystitis isolates, unlike pyelonephritis isolates, were more likely to maintain their invertible elements in the ON orientation for the entire period of infection. E. coli cells expressing type 1 fimbriae, expelled in urine, were shown by scanning electron microscopy to be densely packed on the surface of uroepithelial cells. These results suggest that expression of type 1 fimbriae is more critical for cystitis strains than for pyelonephritis strains in the early stages of an infection during bladder colonization.
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79
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Johnson DE. Hospitalists may help relieve nurse shortage. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:2-3. [PMID: 11374197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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80
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Johnson DE. HealthSouth offers rich content. Web site is a major communications tool for operator of 2,000 facilities: inpatient acute care hospitals and rehab hospitals and outpatient rehab, surgery and diagnostic clinics. PROFILES IN HEALTHCARE MARKETING 2001; 17:42-5. [PMID: 11374132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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81
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Johnson DE. HealthSouth's automated hospital will retain nurses. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:1, 19-22. [PMID: 11374193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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82
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Johnson DE. Web-based data analysis tools help providers, MCOs contain costs. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:16-9. [PMID: 11329971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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83
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Johnson DE. Winning higher rates will be harder this year. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:2-3. [PMID: 11329972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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84
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Johnson DE. Hospitalists' leadership key to IOM's 21st century aims. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:1, 20-2. [PMID: 11329968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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85
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Johnson DE. Chicago's Children's Memorial Hospital uses Web site to welcome parents. PROFILES IN HEALTHCARE MARKETING 2001; 17:47-53. [PMID: 11338370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Publisher Donald E.L. Johnson lets his memories lead him back to Children's Memorial Hospital of Chicago. He reviews its Web site, which fills the demands of concerned parents, who need not only reassurance but also complete information.
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Johnson DE. HIPAA may produce better cash flow for hospitals. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:1, 18-22. [PMID: 11258237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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87
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Johnson DE. Retention may be key to nurse shortage. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:2-3. [PMID: 11258241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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88
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Ignatiev A, Jona F, Debe M, Johnson DE, White SJ, Woodruff DP. Three independent LEED studies of clean Si (100) surfaces. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/10/8/014] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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89
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Johnson DE. HIPAA is new weapon and career opportunity. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:2-3. [PMID: 11219271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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90
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Abstract
The power of genomics in transforming the biotechnology industry will be evident in all areas of drug discovery and development. This will be particularly true in safety evaluation, where the field will be forced to adapt to new schemes of e-R&D and e-business in general. Toxicologists will be required to create information-rich, real-time systems that can be used for decisions in the earliest phases of discovery and throughout development. The largest growth area in specific product types will be those that can move genomics information from the laboratory to the clinic the fastest.
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Johnson DE. Bush, Congress offer opportunities, risks. HEALTH CARE STRATEGIC MANAGEMENT 2001; 19:2-3. [PMID: 11211414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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92
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Johnson DE. Cleveland Clinic Web site promotes status, provides helpful information. PROFILES IN HEALTHCARE MARKETING 2001; 17:40-7, 3. [PMID: 11209296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Publisher Donald E.L. Johnson writes about The Cleveland Clinic Foundation's Web site that both promotes its status as a leading international group practice and medical center and gives patients access to useful medical and health care information.
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Johnson DE, Blower PE, Myatt GJ, Wolfgang GH. Chem-tox informatics: data mining using a medicinal chemistry building block approach. CURRENT OPINION IN DRUG DISCOVERY & DEVELOPMENT 2001; 4:92-101. [PMID: 11727328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Relating chemical structure to biological activity is not a new endeavor, however, the ability to do this on large datasets is just emerging. To cope with the enormous amounts of data being generated, an assortment of computational methods has been developed in the fields of chemoinformatics and computational toxicology. Many of the molecular descriptors used in these approaches are abstract, theoretical constructs that are difficult to understand and visualize. Having easily recognized chemical features, such as those in several new programs, will allow chemists to use toxicological information (or any biological information) when designing new libraries. These improved chem-tox informatics systems will have an impact on library design, hit and lead optimization, development candidate testing and regulatory review.
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Gastman BR, Yin XM, Johnson DE, Wieckowski E, Wang GQ, Watkins SC, Rabinowich H. Tumor-induced apoptosis of T cells: amplification by a mitochondrial cascade. Cancer Res 2000; 60:6811-7. [PMID: 11156370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
We have recently reported that apoptosis of T cells induced by squamous cell carcinoma of the head and neck (SCCHN) is partly Fas dependent. This tumor-induced T-cell death is mediated by the activities of caspase-8 and caspase-3 and is partially inhibited by antibodies to either Fas or Fas ligand. We report here that in contrast to apoptosis induced by agonistic anti-Fas antibody (Ab), the tumor-induced apoptotic cascade in Jurkat cells is significantly amplified by a mitochondrial loop. The involvement of mitochondria in tumor-induced apoptosis of T cells was demonstrated by changes in mitochondrial permeability transition as assessed by 3,3'-dihexiloxadicarbocyanine staining, by cleavage of cytosolic BID and its translocation to the mitochondria, by release of cytochrome c to the cytosol, and by the presence of active subunits of caspase-9 in Jurkat T cells cocultured with tumor cells. To further elucidate the significance of mitochondria in tumor-induced T-cell death, we investigated the effects of various inhibitors of the mitochondrial pathway. Specific antioxidants, as well as two inhibitors of mitochondria permeability transition, bongkrekic acid and cyclosporin A, significantly blocked the DNA degradation induced in Jurkat T cells by SCCHN cells. However, these inhibitors had no effect on cells triggered by anti-Fas Ab. Furthermore, a cell-permeable inhibitor of caspase-9, Ac-LEHD.CHO, which did not inhibit T-cell apoptosis induced by anti-Fas Ab, markedly inhibited apoptosis induced by etoposide or by coculture of Jurkat with SCCHN cells. These findings demonstrate that apoptotic cascades induced in Jurkat T lymphocytes by anti-Fas Ab or tumor cells are differentially susceptible to a panel of inhibitors of mitochondrial apoptotic events. It appears that besides the Fas-mediated pathway, additional mitochondria-dependent cascades are involved in apoptosis of tumor-associated lymphocytes. Inhibition of mitochondria-dependent cascades of caspase activation should be considered to enhance the success of immunotherapy or vaccination protocols in cancer.
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Roehl HH, Leibbrandt ME, Greengard JS, Kamantigue E, Glass WG, Giedlin M, Boekelheide K, Johnson DE, Jolly DJ, Sajjadi NC. Analysis of testes and semen from rabbits treated by intravenous injection with a retroviral vector encoding the human factor VIII gene: no evidence of germ line transduction. Hum Gene Ther 2000; 11:2529-40. [PMID: 11119423 DOI: 10.1089/10430340050208000] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In a phase 1 clinical trial, we are evaluating a murine leukemia virus (MuLV)-based retroviral vector encoding the human factor VIII gene [hFVIII(V)], administered intravenously, as a therapy for hemophilia A. Preclinical biolocalization studies in adult rabbits revealed vector-specific PCR signals in testis tissue at low levels. In follow-up animal studies we used PCR to (1) estimate the frequency with which a given cell in testis tissue is transduced, and (2) determine whether a positive PCR signal could be detected in semen samples from animals treated with hFVIII(V). Using the 99% confidence bound, results indicate that the probability that a given cell within the testis was transduced is less than 1/709,000 (97 days after treatment). This probability decreased with time after hFVIII(V) administration. Moreover, the rate of provector sequence detection in semen samples collected weekly throughout two cycles of spermatogenesis was 3/4281 reactions (0.07%), which is lower than the rate of false positives (1/800, 0.125%) observed for control animals. Using PCR assays with single-copy sensitivity, we have shown that the small number of transduced cells present in testis tissue does not give rise to detectable transduced cells in semen.
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Johnson DE. Web site experimenting can benefit hospitals. HEALTH CARE STRATEGIC MANAGEMENT 2000; 18:2-3. [PMID: 11125938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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97
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Howe JA, Demers GW, Johnson DE, Neugebauer SE, Perry ST, Vaillancourt MT, Faha B. Evaluation of E1-mutant adenoviruses as conditionally replicating agents for cancer therapy. Mol Ther 2000; 2:485-95. [PMID: 11082322 DOI: 10.1006/mthe.2000.0206] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The oncolytic effect of adenoviruses may provide an efficient means to destroy tumor tissue if viruses could be developed with sufficient selectivity and efficacy. In this report we have characterized several adenoviruses, each with different mutations in the E1 region, for selective cytopathic effect in tumor cells in vitro and for their ability to inhibit tumor growth in vivo. Of the E1 mutants tested, we have identified one, E1Adl01/07, which preferentially induces cytopathic effects in a range of tumor cells versus primary cells. In addition, E1Adl01/07 significantly inhibited tumor growth and increased survival of mice in several models of human cancer. These results suggest that E1Adl01/07 might serve as an effective cancer therapeutic, combining both selectivity and efficacy.
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Johnson DE. Internet is just beginning to help hospitals. HEALTH CARE STRATEGIC MANAGEMENT 2000; 18:2-3. [PMID: 11148952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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99
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Johnson DE. Will disruptive innovations cure health care? HARVARD BUSINESS REVIEW 2000; 78:197-198. [PMID: 11184974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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100
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Maser RS, Antoku K, Scully WJ, Cho RL, Johnson DE. Analysis of the role of conserved cysteine residues in the bcl-2 oncoprotein. Biochem Biophys Res Commun 2000; 277:171-8. [PMID: 11027659 DOI: 10.1006/bbrc.2000.3652] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The Bcl-2 oncoprotein is an integral membrane protein localized primarily to the outer membrane of the mitochondria. The precise molecular mechanism responsible for the antiapoptotic action of Bcl-2 remains unknown. Two cysteine residues are found in Bcl-2 and these residues are well-conserved across species. The first cysteine (cys(155)) is located in the alpha5 domain, a region important for the ion channel properties of Bcl-2, while the second cysteine (cys(226)) is located in the carboxyl-terminal membrane anchor domain. In this study, we found that replacement of both cysteines with serine residues generated a mutant protein that retained the ability to homodimerize and heterodimerize with proapoptotic Bax protein in vitro. In whole cells, the mutant protein efficiently heterodimerized with Bax, but exhibited impaired homodimerizationrelative to wild-type Bcl-2. The mutant protein was also less efficient than wild-type Bcl-2 at suppressing caspase activation, DNA fragmentation, and loss of viability during IL-3 withdrawal-induced apoptosis. Together, the data indicate that the cysteine residues in Bcl-2 contribute, but are not absolutely essential, to the ability of Bcl-2 to homodimerize, heterodimerize with Bax, and suppress apoptosis.
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