Biomedical subjects

G G Maul

Publications and source records attributed to G G Maul.

At least 37 records · Page 2Linked to original sources

PubMed1996

Nuclear domain 10 as preexisting potential replication start sites of herpes simplex virus type-1.

The herpes simplex virus type 1 (HSV-1) nuclear replication cycle begins at localized sites, but it has remained unclear whether these sites are associated with any defined nuclear structure. We have previously shown that during infection, the HSV-1 immediate-early protein ICP0 dispersed proteins associated with ND10, nuclear sites that contain high concentrations of PML and other potentially regulatory proteins and correspond to the ultrastructurally defined nuclear bodies. Using in situ hybridization and immunohistochemical techniques, we found that ICP0 mutants of HSV-1 replicate in the close proximity with ND10, but increasing replication sites develop away from these nuclear structures. Input wild-type HSV-1 DNA was found preferentially adjacent to ND10 before ICP0 modified these nuclear structures and did not colocalize with ICP8 containing so-called prereplication sites. The sites where HSV-1 can begin replication then need to be redefined as preexisting potential replication sites. Viral RNA was also found associated with ND10 before early protein synthesis (ICP8), suggesting that input virus genomes are deposited at ND10 before they start replication. The deposition of input viral DNA at ND10 is virus gene expression independent, probably indicating cell regulation of this process. Taken together, these data demonstrate that some very early processes of the nuclear viral replication cycle happen in close proximity or at the periphery of ND10. The localization of input HSV-1 to ND10 represents a new host-virus interaction and provides an unexpected functional property for this large nuclear site.

Antigens, Nuclear↗

PubMed1996

Adenovirus replication is coupled with the dynamic properties of the PML nuclear structure.

Wild-type PML and at least four other novel proteins are localized within discrete nuclear structures known as PODs. We demonstrate here that during adenovirus infection, immediate early viral proteins from the E1 and E4 transcription units associate with the POD, which in turn undergoes a dramatic morphological change. During this process, the auto-antigen Sp-100 and NDP55 but not PML, relocate from the POD to the viral inclusion bodies, the sites of adenovirus DNA replication and late RNA transcription. The E4-ORF3 11-kD protein alone will induce this reorganization and reciprocally, viruses carrying mutations in the E4-domain fail to do so. These same viral mutants are defective in viral replication as well as the accumulation of late viral mRNAs and host cell transcription shutoff. We show that interferon (INF) treatment enhances the expression of PML, reduces or blocks PODs reorganization, and inhibits BrdU incorporation into viral inclusion bodies. In addition, cell lines engineered to overexpress PML prevent PODs from viral-induced reorganization and block or severely delay adenovirus replication. These results suggest that viral replication relies on components of the POD and that the structure is a target of early viral proteins.

Adenovirus E1 Proteins↗

PubMed1996

The periphery of nuclear domain 10 (ND10) as site of DNA virus deposition.

After DNA viruses enter the nucleus, they initiate a transcriptional cascade which is followed by replication. We investigated whether these processes take place at specific nuclear sites or, as suggested by the mode of entry, randomly throughout the nucleus. Three distinct nuclear domains, nuclear factor-1 sites, coiled bodies, and nuclear domain 10 (ND10), were used as markers to investigate the relative position of DNA virus replication sites. We found that all three nuclear domains had a very high spatial correlation with each other in uninfected cells. After adenoviral infection, nuclear factor 1 and coiled bodies were found associated with some viral replication domains. Simian virus 40 begins replication adjacent to ND10 but adenovirus 5 and herpes simplex type 1 modified ND10s before replication. Adenovirus E4orf 3 gene deletion mutants retain ND10 and begin replication at the peripheries of ND10. The same was found for the herpes simplex virus type 1 immediate early gene 1 mutants. That the deposition and replication of adenovirus 5 and herpesvirus type 1 at ND10 was not a mutant phenotype was confirmed by finding the input wild-type virus juxtaposed to ND10. The transport of viral genomes to ND10 does not require viral gene expression. Thus, the peripheries of ND10 represent preferred sites where early steps of transcription and replication of at least three DNA virus families take place, suggesting a new set of functional properties for this large nuclear domain.

Binding Sites↗

PubMed1996

Transplantation of systemic sclerosis (SSc) skin grafts into severe combined immunodeficient mice: increased presence of SSc leukocytes in SSc skin grafts and autoantibody production following autologous leukocyte transfer.

This study was performed to evaluate the potential of the severe combined immunodeficient (Scid) mouse as a model to study the pathogenesis of systemic sclerosis (SSc). Scid mice were divided into three treatment groups: group 1 received skin grafts and autologous peripheral blood mononuclear cells (PBMC) from either SSc patients or normal individuals, group 2 received only SSc or normal skin grafts, and group 3 received only SSc or normal PBMC transfer. Antinuclear antibodies with a similar expression pattern as in the donor patients were detected in SSc-Scid group 1. Increased numbers of human PBMC were detected after autologous PBMC transfer in normal or SSc skin grafts without crossover into the adjacent mouse tissue. The CD4/CD8 ratio in these infiltrates was approximately 1.0. Although SSc skin transplantations and autologous PBMC transfer into Scid mice did not reproduce the inflammatory events found in the original SSc skin biopsies, these mice could be useful to study the expression of SSc-specific autoantibodies.

Adoptive Transfer↗

PubMed1995

Nuclear domain 10 (ND10) associated proteins are also present in nuclear bodies and redistribute to hundreds of nuclear sites after stress.

The promyelocytic leukemia protein fused to the retinoic acid receptor alpha in t(15;17) acute promyelocytic leukemia, the primary biliary cirrhosis autoantigen, Sp100, as well as the incompletely characterized protein NDP55, are co-localized in specific immunohistochemically defined nuclear domains (ND10), which are potential equivalents of ultrastructurally defined nuclear bodies. We investigated whether the distribution of these proteins depends on environmental conditions and whether ND10 correlate with nuclear bodies. Certain nuclear bodies and ND10 react in a similar way and share antigens. Interferon exposure doubled the number of ND10 and increased the frequency of nuclear bodies, whereas herpes simplex virus infection or heat shock modify both. Redistribution of ND10-associated proteins to hundreds of small sites throughout the chromatin was inducible by stress in the form of heat shock and exposure to Cd++ ions. The change of distribution was rapid and independent of protein synthesis, and thus not part of the classical heat shock response. The very rapid redistribution of these proteins after heat shock, together with the development of ND10 upon interferon activation, raises the possibility that ND10 represent storage sites of certain matrix proteins readily accessible throughout the chromatin in response to stress or other effectors that induce global nuclear changes.

Antigens, Nuclear↗

PubMed1995

Molecular characterization of NDP52, a novel protein of the nuclear domain 10, which is redistributed upon virus infection and interferon treatment.

The nuclear domain (ND)10 also described as POD or Kr bodies is involved in the development of acute promyelocytic leukemia and virus-host interactions. Immunofluorescence analysis using a variety of human autoimmune sera and monoclonal antibodies showed a typical dot like nuclear staining for ND10, suggesting that this structure consists of several proteins. Two of the ND10 proteins, Sp100 and PML are genetically characterized and show homology with several transcription factors. Here we describe NDP52, an additional novel protein of the ND10. We raised a new mAb C8A2, that specifically recognizes NDP52. Immunofluorescence analysis using this mAb showed a typical nuclear dot staining as it was described for ND10. Isolation and sequencing of the corresponding cDNA revealed that NDP52 has a predicted molecular mass of 52 kD. The deduced amino acid sequence exhibits an extended central coiled coil domain containing a leucine zipper motif. The COOH terminus of NDP52 shows homology with LIM domains, that have recently been described to mediate protein interactions, which let NDP52 appear as a suitable candidate for mediating interactions between ND10 proteins. In vivo, NDP52 is transcribed in all human tissues analyzed. Furthermore, we show that NDP52 colocalizes with the ND10 protein PML and can be redistributed upon viral infection and interferon treatment. These data suggest that ND10 proteins play an important role in the viral life cycle.

Adenoviridae Infections↗

PubMed1995

The cellular RING finger protein PML is not a functional counterpart of the herpes simplex virus type 1 RING finger protein Vmw110.

Herpes simplex virus type 1 (HSV-1) immediate early protein Vmw110 (also known as ICP0) is required for the fully efficient expression of viral genes during onset of lytic growth and for normal reactivation from latency. Both Vmw110 and the cellular protein PML are members of the RING finger family of zinc binding domain proteins, a family which includes an increasing number of examples from a wide evolutionary range. The function of the RING finger domain is unknown, and the question arises whether the RING finger (like several other examples of conserved domains) fulfils similar functions in these diverse proteins. Another link between Vmw110 and PML is that at early times of HSV-1 infection Vmw110 migrates to distinct nuclear structures which contain the PML protein. In order to test the possibility that PML and Vmw110, or their RING finger domains, fulfill similar functions, we have constructed recombinant viruses that express either intact PML, or a chimeric Vmw110 protein which contains the PML RING finger in place of its own. The results indicate that the PML and Vmw110 RING fingers are not functionally interchangeable, and that PML is not a cellular functional counterpart of Vmw110.

Animals↗

PubMed1995

Mononuclear cellular infiltrates in clinically involved skin from patients with systemic sclerosis of recent onset predominantly consist of monocytes/macrophages.

Systemic sclerosis (SSc) is a generalized autoimmune disorder characterized by immunological abnormalities, microvascular dysfunction, and tissue fibrosis. This study evaluated the inflammatory processes occurring in skin of 7 patients with SSc of recent onset (average disease duration of 10 +/- 3 months) to assess the involvement of monocytes/macrophages during the early stages of SSc. All SSc skin biopsies displayed inflammatory microvascular endothelial cell activation and fibrosis. Increased numbers of infiltrating inflammatory leukocytes were present in affected skin of recent onset SSc (p < 0.01) mainly consisting of CD14-positive monocytes/macrophages (p < 0.02). CD3 T lymphocytes were only slightly elevated in SSc skin (84 +/- 39) compared to normal (51 +/- 12), but the differences were statistically not significant. The ratio of CD14/CD3 cells was substantially higher in affected skin of recent onset SSc (4.0 +/- 2.0) than in normal skin (1.4 +/- 0.5, p < 0.01). Monocytes/macrophages, therefore, are the predominant infiltrating mononuclear cell in skin lesions of recent-onset SSc. These results strongly suggest that CD14-positive monocytes/macrophages play an important role during the early stages of SSc pathogenesis.

Adult↗

PubMed1994

HSV-1 IE protein Vmw110 causes redistribution of PML.

Herpes simplex virus immediate-early protein Vmw110 is required for fully efficient viral gene expression and reactivation from latency. At early times of viral infection, Vmw110 localizes to discrete nuclear structures (known as ND10, PODs or Kr bodies) which contain several cellular proteins, including PML. Interestingly, the unregulated growth of promyelocytic leukaemia cells is correlated with disruption of the normal state of ND10. In this paper we show that: (i) Vmw110 affects the distribution of PML in the cell; (ii) Vmw110 proteins lacking a functional RING finger zinc-binding domain cause the production of striking abnormal cytoplasmic and nuclear structures, some of which contain PML and other ND10 antigens; (iii) a mutant form of Vmw110 which is confined to the cytoplasm appears to result in cytoplasmic PML in some cells; (iv) normal interaction with the nuclear structures requires the C-terminal portion of Vmw110; (v) the C-terminal portion of Vmw110, when linked to a heterologous protein, disrupts the normal distribution of PML. The results suggest that, in normal cells, the PML protein migrates between nucleus and cytoplasm. These observations present an unexpected link between processes involved in the control of cell growth and viral infection and latency.

Animals↗

PubMed1994

A novel macromolecular structure is a target of the promyelocyte-retinoic acid receptor oncoprotein.

Acute promyelocytic leukemia (APL) is associated with a t(15;17) translocation that creates the promyelocyte-retinoic acid receptor alpha (PML-RAR alpha) fusion gene. Immunohistochemistry demonstrates that PML is a part of a novel macromolecular organelle (including at least three other nuclear proteins) referred to as PML oncogenic domains (PODs). In APL cells, the POD is disrupted into a microparticulate pattern as a consequence of the expression of the PML-RAR oncoprotein. RA treatment of APL cells triggers a reorganization of PML to generate normal-appearing PODs. We propose that PML-RAR is a dominant negative oncoprotein that exerts its putative leukomogenic effect by inhibiting assembly of the POD. According to this proposal, not only is the POD a novel structure, but it can be ascribed an imputed function such that its disruption leads to altered myeloid maturation; this may represent a novel oncogenic target.

Cell Nucleus↗

PubMed1994

Characterization of a major nucleoplasmin-like germinal vesicle protein which is rapidly phosphorylated before germinal vesicle breakdown in Spisula solidissima.

Oocytes of the surf clam, Spisula solidissima, are arrested at the G2/M boundary of meiotic prophase I. At this stage, they possess a prominent germinal vesicle (GV), comprising about 25% of the total oocyte volume, in which pools of mRNAs and proteins that facilitate the rapid rounds of cell division which occur early in development are stored. We have isolated and characterized an abundant 49-kDa phosphoprotein, localized exclusively to the GV, which shares properties with nucleoplasmin. Like nucleoplasmin, this 49-kDa protein is a heat-stable, highly acidic phosphoprotein [containing over 32% (Glx + Asx) with an isoelectric point of about 4.0] and is soluble in 80% ammonium sulfate. In contrast to the pentameric nucleoplasmin, much of this protein is isolated as a disulfide-linked multimer which migrates at 120 kDa. In addition, a fraction of the 49-kDa protein is associated via disulfide bonds to a doublet of 42-kDa proteins. In vivo, this 49-kDa protein is phosphorylated prior to germinal vesicle breakdown (GVBD) and at 5 min after oocyte activation rapidly incorporates 32P to 60% of maximal level, suggesting that this protein plays a major role in the cascade of events which lead to oocyte activation and GVBD.

Animals↗

PubMed1994

The nuclear location of PML, a cellular member of the C3HC4 zinc-binding domain protein family, is rearranged during herpes simplex virus infection by the C3HC4 viral protein ICP0.

ND10 are nuclear domains of unknown function that become abundant in response to stress. Infection by herpes simplex virus type 1 (HSV-1) causes the apparent disappearance of these domains, an effect that requires the expression of the immediate early protein ICP0. Previously, we have shown that there are a number of cellular antigens in the ND10. In this report, we show that one of these proteins is PML, a member of the C3HC4 zinc-binding domain family which also includes ICP0. The C3HC4 domain of ICP0 is essential for the apparent release of PML from the ND10, although the interaction of ICP0 with ND10 is determined by a small region near its carboxy terminus. PML and other ND10 proteins are not lost after removal from ND10 but deposited at the nuclear envelope or nuclear envelope modifications during later parts of the replication cycle. ICP0 is required for the onset of low multiplicity infections, and has been implicated in the process of reactivation from HSV latency. Therefore, the interaction between ICP0 and the ND10 domains, specifically PML, may be important for the outcome of virus-cell interactions.

Cell Nucleus↗

PubMed1994

Isolation and characterization of microvascular endothelial cells from the adult human dermis and from skin biopsies of patients with systemic sclerosis.

BACKGROUND: Systemic sclerosis (SSc) is a rheumatic autoimmune disease without known etiology and pathogenesis. Inflammatory processes with selective microvascular involvement seem to play an important role in the early stages of SSc. EXPERIMENTAL DESIGN: To elucidate the pathogenesis of the selective microvascular involvement in SSc, we have isolated microvascular endothelial cells from the adult human dermis (ADMEC) and for the first time from skin biopsies of patients with SSc (SSc-ADMEC) and established in cell culture. Ulex europaeus I-coated magnetic Dynabeads and the perfusion digestion technique were applied for endothelial cell isolation. RESULTS: The cultured ADMEC and SSc-ADMEC showed the endothelial cell-specific antigenic determinants of intracellular von Willebrand factor and platelet endothelial cell adhesion molecule-1 along their cell-cell borders. These cells displayed specific uptake of acetylated low-density lipoprotein. Normal ADMEC were additionally characterized for angiotensin I-converting enzyme activity. Tumor necrosis factor-alpha activated normal ADMEC and SSc-ADMEC expressed the inflammatory adhesion molecules E-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, similarly to tumor necrosis factor-alpha-activated large-vessel endothelium represented by human umbilical cord vein endothelial cells. Normal ADMEC and human umbilical cord vein endothelial cells also expressed beta 1- and beta 4-integrin receptors in cell culture. CONCLUSIONS: Normal ADMEC and SSc-ADMEC express endothelial cell-specific antigenic and biochemical determinants in vitro. SSc-ADMEC were for the first time established in cell culture.

Adult↗

PubMed1993

Modification of discrete nuclear domains induced by herpes simplex virus type 1 immediate early gene 1 product (ICP0).

The outcome of herpes simplex virus type 1 (HSV-1) infection depends upon the interplay of both host and viral factors. During lytic infection, HSV-1 causes a loss of immunofluorescent staining of discrete nuclear domains (ND10). This elimination of the host's ND10 staining occurs under conditions that allow only HSV-1 immediate early viral gene expression. Western blot analysis indicates that the loss of ND10 staining is due to ND10 redistribution, rather than protein degradation or turnover. When deletion mutants of all of the HSV-1 immediate early genes were tested, only infection with an immediate early gene 1 product (ICP0) deletion mutant, d11403, was unable to eliminate ND10 antigen staining. Also, ICP0 transiently colocalized with ND10 antigens, after which ND10 antigens became undetectable. At late times during infection with d11403, the host ND10 antigens were retained in virus-induced structures which were never observed during wild-type HSV-1 infection. These results suggested that ICP0 may be directly involved in the modification of the host nuclear domain. Infection with an adenovirus recombinant that expressed ICP0 demonstrated that in the absence of other HSV-1 proteins ICP0 was sufficient for the change in nuclear distribution of host antigens located at ND10. We postulate that the trans-activation function of ICP0 during viral replication may be mediated by replacing, modifying or reorganizing nuclear host factors.

Animals↗

PubMed1992

Autoantibodies to nuclear lamin C in the eosinophilia-myalgia syndrome associated with L-tryptophan ingestion.

OBJECTIVE: To examine the autoantibodies (antinuclear antibodies [ANA]) present in serum from a patient with eosinophilia-myalgia syndrome (EMS). METHODS: Sera obtained during the early phase of EMS and following therapy with prednisone were screened by indirect immunofluorescence on HEp-2 cells, and ANA were characterized by immunoblotting on a purified nuclear lamin fraction. RESULTS: ANA with a ring-like pattern of nuclear staining were identified at high titer by immunofluorescence, and immunoblotting experiments showed them to be directed against lamin C. The antibody titer declined dramatically after discontinuation of L-tryptophan and therapy with prednisone. CONCLUSION: This is the first characterization of an antigen/autoantibody system associated with EMS. The findings indicate that this EMS-associated autoantibody recognizes epitopes localized in the carboxyterminal region of lamin C. The occurrence of anti-lamin C autoantibodies in one EMS patient expands the spectrum of clinical conditions associated with these antibodies, and provides evidence for an autoimmune response in EMS.

Administration, Oral↗

PubMed1992

Receptor utilization by reovirus type 3: distinct binding sites on thymoma and fibroblast cell lines result in differential compartmentalization of virions.

Reovirus type 3/D infects cells following binding to specific cell-surface receptors. The characteristics of these receptors may play an important role in determining post-binding events critical to the viral life cycle. Some cell lines, i.e. L-cells, appear to bind reovirus type 3/D utilizing sialylated proteins as specific receptors for viral adsorption. Such binding results in productive infection. Other cell lines, i.e. R1.1 thymoma cells, bind reovirus type 3/D in a sialic acid independent manner which does not result in productive infection. Yet, a peptide analogue of the viral binding site is capable of inhibiting binding of reovirus type 3 to both cell types, suggesting the same viral epitope interacts with both cellular receptors. When binding of reovirus is studied by electron microscopy, the virus particles enter the L cells via coated pits, and are later seen in large accumulations in endocytic vesicles near the transGolgi network. In contrast, R1.1 cells appear to divert the reovirus particles to a cell membrane elaboration, with reovirus remaining bound to the cell membrane. At later time points with R1.1 cells, there are no apparent intracellular accumulations. These studies demonstrate that viruses can attach to different cells utilizing distinct receptors, and this may play a role in the ability of the virions to productively infect the cells. The capacity of virus to be adsorbed to cellular receptors which do not lead to internalization may be an important mechanism for the sequestration and clearance of virus. These observations have implications for the tissue tropism demonstrated by reovirus type 3/D and other viruses.

Amino Acid Sequence↗

PubMed1991

The expression of nuclear lamin A and C epitopes is regulated by the developmental stage of the cytoplasm in mouse oocytes or embryos.

The cytoplasmic regulation of changes of nuclear lamin antigens was examined by transferring 16-cell stage blastomeres into mouse oocytes. Sixteen-cell stage blastomeres were transferred to either pronuclear eggs, enucleated pronuclear eggs or metaphase II oocytes, which were subsequently activated. Pronuclei react with a monoclonal antibody to A/C lamins (J9), whereas nuclei from 16-cell stage blastomeres do not react with J9. However, after transfer of 16-cell stage nuclei to activated metaphase II oocytes, the transferred nuclei acquire the antigen. This is in contrast to 16-cell nuclei that were transferred to intact or enucleated pronuclear eggs; i.e., the nuclei only faintly acquired the A/C epitope. These results suggest that the developmental stage of the cytoplasm regulates the exposure of nuclear lamina epitopes, perhaps by limiting the supply of lamin A/C in the oocyte or because nuclear lamina assembly can only occur at the telophase transition. Furthermore, it appears that there is some exchange of the A/C epitope between (pro)nuclei within the same cell but that the majority of the A/C lamin epitope can be removed from a cell with (pro)nuclear removal.

Animals↗

PubMed1991

Cytoplasmic modification of the nuclear lamina during pronuclear-like transformation of mouse blastomere nuclei.

During the successive interphases of cleaving mouse embryos the nuclear periphery diminishes its reactivity to anti-lamin A and C antibodies. This developmentally regulated characteristic can be modified by exposure of the blastomere nuclei to metaphase II (M II) oocyte cytoplasm followed by activation. In the current study we define the cytoplasmic conditions necessary for this modification of 8-cell and 16-cell stage nuclei in hybrids obtained by fusion with metaphase II arrested oocytes, oocytes at various time points after parthenogenetic activation, naturally fertilized eggs (zygotes) and interphase 2-cell embryo blastomeres. The intensity of fluorescence obtained with anti-lamins A/C in the blastomere nuclei increases as a result of fusion with freshly activated oocytes or early zygotes (first 3.0-5.5 h in the case of parthenogenetic activation), and not when eggs or 2-cell blastomeres advanced in interphase are used as partners for fusion. This transformation of the A/C lamin pattern is correlated with the ability to promote pronucleus-like growth of blastomere nuclei in hybrids. Blastomere nuclei introduced into M II-arrested oocytes undergo premature chromatin condensation and dissolution of the nuclear lamina. The results are discussed with regard to certain particularities of the first embryonic interphase of the mouse and the potential involvement of nuclear lamins in pronuclear growth.

Animals↗