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Loewen M, Ashikari A, Kelemen P, Salzberg A, Savino J, Ashikari R. Cowden Syndrome as an indication for bilateral prophyllactic mastectomy: A series of two cases. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.10761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
10761 Background: Multiple hamartoma syndrome, or Cowden Syndrome, is an autosomal dominant disorder which predisposes toward neoplasms in the thyroid, colon, and breast. Chemoprevention in women with a genetic predisposition toward breast cancer has not yet been shown to be beneficial in prospective data. Bilateral prophylactic mastectomy (BMP) has emerged as a viable option for women with suspected genetic predispositions toward breast cancer, with an estimated risk reduction of around 90 percent. Our search of the literature has not detected any case series of BMP in the Cowden Syndrome patients. Methods: We present two women presenting with historical and physical evidence for this Cowden Syndrome with desire to undergoing PBM. Results: Both women successfully underwent subcutaneous bilateral mastectomy with immediate reconstruction. (See table ) They are both alive without evidence of breast cancer to date. Conclusions: Cowden Syndrome can be added to other genetic syndromes with clear predispositions toward breast cancer, and presents an option for prophylactic bilateral mastectomy in women who desire a risk reduction for breast cancer. [Table: see text] No significant financial relationships to disclose.
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Affiliation(s)
- M. Loewen
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
| | - A. Ashikari
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
| | - P. Kelemen
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
| | - A. Salzberg
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
| | - J. Savino
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
| | - R. Ashikari
- New York Medical College, Lake Peekskill, NY; New York Medical College, Valhalla, NY
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Inbal A, Halachmi N, Dibner C, Frank D, Salzberg A. Genetic evidence for the transcriptional-activating function of Homothorax during adult fly development. Development 2001; 128:3405-13. [PMID: 11566847 DOI: 10.1242/dev.128.18.3405] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Homothorax (HTH) is a homeobox-containing protein, which plays multiple roles in the development of the embryo and the adult fly. HTH binds to the homeotic cofactor Extradenticle (EXD) and translocates it to the nucleus. Its function within the nucleus is less clear. It was shown, mainly by in vitro studies, that HTH can bind DNA as a part of ternary HTH/EXD/HOX complexes, but little is known about the transcription regulating function of HTH-containing complexes in the context of the developing fly. Here we present genetic evidence, from in vivo studies, for the transcriptional-activating function of HTH. The HTH protein was forced to act as a transcriptional repressor by fusing it to the Engrailed (EN) repression domain, or as a transcriptional activator, by fusing it to the VP16 activation domain, without perturbing its ability to translocate EXD to the nucleus. Expression of the repressing form of HTH in otherwise wild-type imaginal discs phenocopied hth loss of function. Thus, the repressing form was working as an antimorph, suggesting that normally HTH is required to activate the transcription of downstream target genes. This conclusion was further supported by the observation that the activating form of HTH caused typical hth gain-of-function phenotypes and could rescue hth loss-of-function phenotypes. Similar results were obtained with XMeis3, the Xenopus homologue of HTH, extending the known functional similarity between the two proteins. Competition experiments demonstrated that the repressing forms of HTH or XMeis3 worked as true antimorphs competing with the transcriptional activity of the native form of HTH. We also describe the phenotypic consequences of HTH antimorph activity in derivatives of the wing, labial and genital discs. Some of the described phenotypes, for example, a proboscis-to-leg transformation, were not previously associated with alterations in HTH activity. Observing the ability of HTH antimorphs to interfere with different developmental pathways may direct us to new targets of HTH. The HTH antimorph described in this work presents a new means by which the transcriptional activity of the endogenous HTH protein can be blocked in an inducible fashion in any desired cells or tissues without interfering with nuclear localization of EXD.
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Affiliation(s)
- A Inbal
- Unit of Genetics, Department of Biochemistry, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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3
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Abstract
The evolutionarily conserved basic helix-loop-helix (bHLH) transcription factors play important roles during development. Here we report the identification of Nato3 (nephew of atonal fer3) orthologs in Drosophila, C. elegans, mouse, and man, all of which share a high degree of similarity within the bHLH domain. Expression analysis revealed Nato3 transcripts in the central nervous system of both fly and mouse embryos. In the fly, Dnato3 is highly expressed in 9-15h embryos in a few ventral nerve cord cells and a subset of neurons in the brain. In mouse, the MNato3 transcripts were detected from embryonic day 7 until 5 weeks postnatally, with highest levels in the midbrain, thalamus, hypothalamus, pons, and medulla oblongata. In contrast to the brain, expression in the spinal cord was limited to the embryonic stages.
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Affiliation(s)
- E Segev
- Department of Cell and Animal Biology, Institute of Life Sciences, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel
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4
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Abstract
The homothorax (hth) gene is involved in multiple aspects of embryonic and adult fly development. It encodes a homeodomain-containing protein of the MEIS family and was shown to regulate the subcellular localization of the homeotic protein cofactor Extradenticle (EXD). The HTH protein contains a TALE class homeodomain and a conserved MH domain, which is required for its interaction with EXD. In this work, we describe the structure of the hth locus, characterize at the molecular level a collection of mutant alleles of hth, and discuss the correlation between the identified structural defects and their consequent phenotypes. The hth locus spans more than 100 kb and contains 14 exons. Several of the exon-intron boundaries within the homeodomain and the MH domain-coding regions are conserved between Drosophila and Caenorhabditis elegans. The analysis of hth mutations demonstrates that the homeodomain of HTH is not required for nuclear localization of EXD and that the MH domain-containing first 240 residues are sufficient for nuclear localization of both EXD and HTH. Mutations that alter or delete the homeodomain cause only partial homeotic transformations in the PNS, whereas mutations affecting the MH domain cause distinct and more severe PNS phenotypes. These observations may suggest that driving nuclear localization of EXD is the main role of HTH in patterning the embryonic PNS. They may also suggest that homeodomain-defective HTH protein retains some of its transcription-regulating functions by binding DNA via its interaction with EXD.
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Affiliation(s)
- E Kurant
- Unit of Genetics, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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5
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Abstract
A homologue of the Drosophila homothorax (hth) gene, Xenopus Meis3 (XMeis3), was cloned from Xenopus laevis. XMeis3 is expressed in a single stripe of cells in the early neural plate stage. By late neurula, the gene is expressed predominantly in rhombomeres two, three and four, and in the anterior spinal cord. Ectopic expression of RNA encoding XMeis3 protein causes anterior neural truncations with a concomitant expansion of hindbrain and spinal cord. Ectopic XMeis3 expression inhibits anterior neural induction in neuralized animal cap ectoderm explants without perturbing induction of pan-neural markers. In naive animal cap ectoderm, ectopic XMeis3 expression activates transcription of the posteriorly expressed neural markers, but not pan-neural markers. These results suggest that caudalizing proteins, such as XMeis3, can alter A-P patterning in the nervous system in the absence of neural induction. Regionally expressed proteins like XMeis3 could be required to overcome anterior signals and to specify posterior cell fates along the A-P axis.
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Affiliation(s)
- A Salzberg
- Department of Biochemistry, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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6
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Adams RR, Tavares AA, Salzberg A, Bellen HJ, Glover DM. pavarotti encodes a kinesin-like protein required to organize the central spindle and contractile ring for cytokinesis. Genes Dev 1998; 12:1483-94. [PMID: 9585508 PMCID: PMC316841 DOI: 10.1101/gad.12.10.1483] [Citation(s) in RCA: 280] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mutations in the Drosophila gene pavarotti result in the formation of abnormally large cells in the embryonic nervous system. In mitotic cycle 16, cells of pav mutant embryos undergo normal anaphase but then develop an abnormal telophase spindle and fail to undertake cytokinesis. We show that the septin Peanut, actin, and the actin-associated protein Anillin, do not become correctly localized in pav mutants. pav encodes a kinesin-like protein, PAV-KLP, related to the mammalian MKLP-1. In cellularized embryos, the protein is localized to centrosomes early in mitosis, and to the midbody region of the spindle in late anaphase and telophase. We show that Polo kinase associates with PAV-KLP with which it shows an overlapping pattern of subcellular localization during the mitotic cycle and this distribution is disrupted in pav mutants. We suggest that PAV-KLP is required both to establish the structure of the telophase spindle to provide a framework for the assembly of the contractile ring, and to mobilize mitotic regulator proteins.
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Affiliation(s)
- R R Adams
- Cancer Research Campaign (CRC) Laboratories, Cell Cycle Genetics Research Group, Department of Anatomy and Physiology, Medical Sciences Institute, University of Dundee, Dundee DD1 4HN, UK.
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7
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Pratt CB, Maurer HM, Gieser P, Salzberg A, Rao BN, Parham D, Thomas PR, Marcus RB, Cantor A, Pick T, Green D, Neff J, Jenkins JJ. Treatment of unresectable or metastatic pediatric soft tissue sarcomas with surgery, irradiation, and chemotherapy: a Pediatric Oncology Group study. Med Pediatr Oncol 1998; 30:201-9. [PMID: 9473754 DOI: 10.1002/(sici)1096-911x(199804)30:4<201::aid-mpo1>3.0.co;2-k] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The objectives of this study were to compare vincristine/actinomycin D/cyclophosphamide/adriamycin (VACA) with VACA/plus imidazole carboxamide (DTIC) (VACAD) therapy in regards to complete/partial response and event free survival rates in children and adolescents with metastatic non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) or previously chemotherapy-naive recurrent NRSTS or locally persistent gross residual tumor after surgery and radiation therapy. PROCEDURES Between 1986 and March 1994, 75 patients entered this randomized study comparing VACA and VACAD, given at 3 week intervals. Sixty-one patients were considered eligible and received chemotherapy and radiation therapy to the primary tumor and areas of metastases. Thirty-six patients had regional unresected (Group III) disease, and 25 had metastatic disease (Group IV) at time of accession. Thirty-six patients received VACA (11 were not randomized), and 25 received VACAD. RESULTS With a median follow-up of greater than 4 years, overall and event-free survival for all eligible patients are 30.6% and 18.4% respectively (S.E: 9.5% and 6.8%). There was insufficient evidence that DTIC offered any advantage to event free survival, but there was evidence for better outcome for patients in Group III disease in comparison to patients with Group IV disease, and for patients with a Grade 1 and 2 histology in comparison to Grade 3 lesions. CONCLUSIONS Combination chemotherapy with VACA and VACAD were insufficient to prevent recurrent or progressive disease in children and adolescents with high stage NRSTS. The use of vincristine/ifosfamide/doxorubicin with cytokine support is under study.
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Affiliation(s)
- C B Pratt
- Department of Hematology-Oncology, St Jude Children's Hospital, Memphis, TN 38105, USA
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8
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Kurant E, Pai CY, Sharf R, Halachmi N, Sun YH, Salzberg A. Dorsotonals/homothorax, the Drosophila homologue of meis1, interacts with extradenticle in patterning of the embryonic PNS. Development 1998; 125:1037-48. [PMID: 9463350 DOI: 10.1242/dev.125.6.1037] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The homeotic genes of the bithorax complex are required, among other things, for establishing the patterns of sensory organs in the embryonic peripheral nervous system (PNS). However, the molecular mechanisms by which these genes affect pattern formation in the PNS are not understood and other genes that function in this pathway are not characterized. Here we report the phenotypic and molecular analysis of one such gene, homothorax (hth; also named dorsotonals). Mutations in the hth gene seem to alter the identity of the abdominal chordotonal neurons, which depend on Abd-A for their normal development. However, these mutations do not alter the expression of the abd-A gene, suggesting that hth may be involved in modulating abd-A activity. We have generated multiple mutations in the hth locus and cloned the hth gene. hth encodes a homeodomain-containing protein that is most similar to the murine proto-oncogene meis1. The hth gene is expressed throughout embryonic development in a spatially restricted pattern, which is modulated in abdominal segments by abd-A and Ubx. The spatial distribution of the HTH protein during embryonic development is very similar to the distribution of the Extradenticle (EXD) protein, a known modulator of homeotic gene activity. Here we show that the PNS phenotype of exd mutant embryos is virtually indistinguishable from that of hth mutant embryos and does not simply follow the homeotic transformations observed in the epidermis. We also show that the HTH protein is present in extremely low levels in embryos lacking exd activity as compared to wild-type embryos. In contrast, the EXD protein is present in fairly normal levels in hth mutant embryos, but fails to accumulate in nuclei and remains cytoplasmic. Ectopic expression of hth can drive ectopic nuclear localization of EXD. Based on our observations we propose that the genetic interactions between hth and exd serve as a novel mechanism for regulating homeotic protein activity in embryonic PNS development.
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Affiliation(s)
- E Kurant
- Unit of Genetics, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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9
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Pai CY, Kuo TS, Jaw TJ, Kurant E, Chen CT, Bessarab DA, Salzberg A, Sun YH. The Homothorax homeoprotein activates the nuclear localization of another homeoprotein, extradenticle, and suppresses eye development in Drosophila. Genes Dev 1998; 12:435-46. [PMID: 9450936 PMCID: PMC316489 DOI: 10.1101/gad.12.3.435] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The Extradenticle (Exd) protein in Drosophila acts as a cofactor to homeotic proteins. Its nuclear localization is regulated. We report the cloning of the Drosophila homothorax (hth) gene, a homolog of the mouse Meis1 proto-oncogene that has a homeobox related to that of exd. Comparison with Meis1 finds two regions of high homology: a novel MH domain and the homeodomain. In imaginal discs, hth expression coincides with nuclear Exd. hth and exd also have virtually identical, mutant clonal phenotypes in adults. These results suggest that hth and exd function in the same pathway. We show that hth acts upstream of exd and is required and sufficient for Exd protein nuclear localization. We also show that hth and exd are both negative regulators of eye development; their mutant clones caused ectopic eye formation. Targeted expression of hth, but not of exd, in the eye disc abolished eye development completely. We suggest that hth acts with exd to delimit the eye field and prevent inappropriate eye development.
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Affiliation(s)
- C Y Pai
- Institute of Molecular Biology, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China
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10
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Salzberg A, Prokopenko SN, He Y, Tsai P, Pál M, Maróy P, Glover DM, Deák P, Bellen HJ. P-element insertion alleles of essential genes on the third chromosome of Drosophila melanogaster: mutations affecting embryonic PNS development. Genetics 1997; 147:1723-41. [PMID: 9409832 PMCID: PMC1208342 DOI: 10.1093/genetics/147.4.1723] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
To identify novel genes and to isolate tagged mutations in known genes that are required for the development of the peripheral nervous system (PNS), we have screened a novel collection of 2460 strains carrying lethal or semilethal P element insertions on the third chromosome. Monoclonal antibody 22C10 was used as a marker to visualize the embryonic PNS. We identified 109 mutant strains that exhibited reproducible phenotypes in the PNS. Cytological and genetic analyses of these strains indicated that 87 mutations affect previously identified genes: tramtrack (n = 18 alleles), string (n = 15), cyclin A (n = 13), single-minded (n = 13), Delta (n = 9), neuralized (n = 4), pointed (n = 4), extra macrochaetae (n = 4), prospero (n = 3), tartan (n = 2), and pebble (n = 2). In addition, 13 mutations affect genes that we identified recently in a chemical mutagenesis screen designed to isolate similar mutants: hearty (n = 3), dorsotonals (n = 2), pavarotti (n = 2), sanpodo (n = 2), dalmatian (n = 1), missensed (n = 1), senseless (n = 1), and sticky ch1 (n = 1). The remaining nine mutations define seven novel complementation groups. The data presented here demonstrate that this collection of P elements will be useful for the identification and cloning of novel genes on the third chromosome, since >70% of mutations identified in the screen are caused by the insertion of a P element. A comparison between this screen and a chemical mutagenesis screen undertaken earlier highlights the complementarity of the two types of genetic screens.
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Affiliation(s)
- A Salzberg
- Howard Hughes Medical Institute, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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Salzberg A, Golden K, Bodmer R, Bellen HJ. gutfeeling, a Drosophila gene encoding an antizyme-like protein, is required for late differentiation of neurons and muscles. Genetics 1996; 144:183-96. [PMID: 8878684 PMCID: PMC1207492 DOI: 10.1093/genetics/144.1.183] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The gutfeeling (guf) gene was uncovered in a genetic screen for genes that are required for proper development of the embryonic peripheral nervous system. Mutations in guf cause defects in growth cone guidance and fasciculation and loss of expression of several neuronal markers in the embryonic peripheral and central nervous systems. guf is required for terminal differentiation of neuronal cells. Mutations in guf also affect the development of muscles in the embryo. In the absence or guf activity, myoblasts are formed properly, but myoblast fusion and further differentiation of muscle fibers is severely impaired. The guf gene was cloned and found to encode a 21-kD protein with a significant sequence similarity to the mammalian ornithine decarboxylase antizyme (OAZ). In mammals, OAZ plays a key regulatory role in the polyamine biosynthetic pathway through its binding to, and inhibition of, ornithine decarboxylase (ODC), the first enzyme in the pathway. The elaborate regulation of ODC activity in mammals still lacks a defined developmental role and little is known about the involvement of polyamines in cellular differentiation. GUF is the first antizyme-like protein identified in invertebrates. We discuss its possible developmental roles in light of this homology.
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Affiliation(s)
- A Salzberg
- Howard Hughes Medical Institute, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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Affiliation(s)
- A Salzberg
- Department of Molecular and Human Genetics, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas
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13
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Kania A, Salzberg A, Bhat M, D'Evelyn D, He Y, Kiss I, Bellen HJ. P-element mutations affecting embryonic peripheral nervous system development in Drosophila melanogaster. Genetics 1995; 139:1663-78. [PMID: 7789767 PMCID: PMC1206492 DOI: 10.1093/genetics/139.4.1663] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The Drosophila embryonic peripheral nervous system (PNS) is an excellent model system to study the molecular mechanisms governing neural development. To identify genes controlling PNS development, we screened 2000 lethal P-element insertion strains. The PNS of mutant embryos was examined using the neural specific marker MAb 22C10, and 92 mutant strains were retained for further analysis. Genetic and cytological analysis of these strains shows that 42 mutations affect previously isolated genes that are known to be required for PNS development: longitudinals lacking (19), mastermind (15), numb (4), big brain (2), and spitz (2). The remaining 50 mutations were classified into 29 complementation groups and the P-element insertions were cytologically mapped. The mutants were classified in five major classes on the basis of their phenotype: gain of neurons, loss of neurons, organizational defects, pathfinding defects and morphological defects. Herein we report the preliminary phenotypic characterization of each of these complementation groups as well as the embryonic lacZ expression pattern of each P-element strain. Our analysis indicates that in most of the P-element insertion strains, the lacZ reporter gene is not expressed in the developing PNS.
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Affiliation(s)
- A Kania
- Howard Hughes Medical Institute, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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14
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Schulze KL, Littleton JT, Salzberg A, Halachmi N, Stern M, Lev Z, Bellen HJ. rop, a Drosophila homolog of yeast Sec1 and vertebrate n-Sec1/Munc-18 proteins, is a negative regulator of neurotransmitter release in vivo. Neuron 1994; 13:1099-108. [PMID: 7946348 DOI: 10.1016/0896-6273(94)90048-5] [Citation(s) in RCA: 135] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The mammalian homolog of the yeast Sec1p, n-Sec1/Munc-18 has been demonstrated to bind the presynaptic membrane protein syntaxin, a putative synaptic vesicle docking protein. To determine the role of n-Sec1/Munc-18 in neurotransmitter release in vivo, we have overexpressed the Drosophila homolog, rop, in third instar larvae and measured the electrophysiological consequences at the neuromuscular junction. A 3- to 5-fold induction of the rop protein causes a dramatic decrease in neurotransmitter release, suggesting rop may restrict the ability of vesicles to dock or of docked vesicles to fuse. Consistent with this hypothesis, rop overexpression also reduces the number of spontaneous vesicle fusions by more than 50%, and repetitive stimulation results in significant decreases in evoked responses similar to those observed in rab3a mutant mice. However, rop overexpression does not alter significantly the Ca2+ dependence of neurotransmitter release. We propose that the Drosophila n-Sec1/Munc-18 homolog plays a negative role in neurotransmitter release in vivo, in addition to its previously identified positive function, possibly by modulation of docking of synaptic vesicles or activation of a pre-fusion complex at the active zone.
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Affiliation(s)
- K L Schulze
- Howard Hughes Medical Institute, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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15
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Ezer ST, Sahar D, Salzberg A, Lev Z. Differential expression during embryogenesis of three genes clustered in the Ras1 region of Drosophila melanogaster. Dev Dyn 1994; 201:179-90. [PMID: 7873789 DOI: 10.1002/aja.1002010208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Transcription mapping and nucleotide sequence analysis reveal that the genomic region of the Drosophila Ras1 gene contains a cluster of three closely localized genes. A gene termed Rlb1 is located nearby and upstream of Ras1, and is oriented in the opposite polarity relative to Ras1. In addition, a third gene termed Rlc1, is found at a very close proximity downstream to Rlb1. Ras1, the homologue of the human transforming ras genes, has been shown to be active in the posterior termini of the Drosophila embryo and in the eye imaginal disc in pathways of cell fate determination. We demonstrate that during embryogenesis Ras1 transcripts are restricted mainly to the embryonic central nervous system, suggesting that the gene product also may have a role in these nerve cells. Rlb1 encodes for a novel, lysine-rich basic protein. It is expressed mainly in the developing midgut and in the somatic mesoderm. Rlc1 also encodes for a novel, basic protein. The expression of Rlc1 during embryogenesis is similar, but not identical, to the expression pattern detected for Ras1. The vertebrate p21Ras proteins are bound to the inner face of the cell membrane. Ras1, the Drosophila homologue of p21, and the Rlb1 protein, are also non-cytoplasmic, membranous proteins. Rlb1 is found in the cell membrane of larval midgut epithelial cells. In addition, Rlb1 is detected in the nuclei of these cells, and in the nuclei of the midgut imaginal cells.
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Affiliation(s)
- S T Ezer
- Department of Biology, Technion-Israel Institute of Technology, Haifa
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16
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Salzberg A, D'Evelyn D, Schulze KL, Lee JK, Strumpf D, Tsai L, Bellen HJ. Mutations affecting the pattern of the PNS in Drosophila reveal novel aspects of neuronal development. Neuron 1994; 13:269-87. [PMID: 8060613 DOI: 10.1016/0896-6273(94)90346-8] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Through a systematic genetic screen, we have identified 55 mutations that affect the development of the PNS of Drosophila embryos. These mutations specify 13 novel and 5 previously characterized genes and define new phenotypes for 2 other known genes. Five classes of mutant phenotypes were identified in the screen: gain of neurons, loss of neurons, abnormal position of chordotonal neurons, aberrant neuronal trajectories, and abnormal morphology of neurons. Phenotypic analyses of mutations identified in this study revealed three novel aspects of PNS development. First, we have identified a novel gene that may be required to define glial versus neuronal cell identity. Second, our data indicate that neuronal migration plays an important role in pattern formation in the embryonic PNS. Third, we have identified mutations that cause a lack of sensory organs, but unlike mutations in proneural genes, do not affect the formation of sensory organ precursors. These genes may be required for key aspects of neuronal differentiation. Our studies suggest that approximately 70 essential genes are required for proper PNS development in Drosophila embryos.
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Affiliation(s)
- A Salzberg
- Howard Hughes Medical Institute, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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17
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Salzberg A, Cohen N, Halachmi N, Kimchie Z, Lev Z. The Drosophila Ras2 and Rop gene pair: a dual homology with a yeast Ras-like gene and a suppressor of its loss-of-function phenotype. Development 1993; 117:1309-19. [PMID: 8404533 DOI: 10.1242/dev.117.4.1309] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The promoter of the Drosophila melanogaster Ras2 gene is bidirectional, regulating an additional gene oriented in the opposite polarity. The two divergently transcribed genes are only 93 bases apart and deletion analysis proved that common cis-acting elements within this promoter region are required for the transcriptional activity of both genes. We cloned the gene paired with Ras2 in the bidirectional promoter and isolated cDNAs corresponding to its mRNA. The Ras opposite (Rop) gene encodes for a 68 × 10(3) M(r) protein which shares sequence homology with the members of a novel Saccharomyces cerevisiae gene family, including the SLY1, SEC1 and VPS33 (SLP1) genes, all of which are involved in vesicle trafficking among yeast cellular compartments. A highly conserved motif in this family is also found in beta-COP, a coat protein isolated from rat Golgi-bound nonclathrin vesicles. Thus, the Rop protein may be a component of one of the vesicle trafficking pathways in Drosophila cells. The Rop gene expression during embryogenesis is restricted to the central nervous system (CNS) and the garland cells, a small group of nephrocytes that takes up waste materials from the haemolymph by endocytosis. Ras2 is also expressed in the embryonic garland cells. In postembryonic stages, the two genes are co-expressed in the larval salivary glands and the central nervous system, and in the adult CNS and reproductive systems. Interestingly, the S. cerevisiae SLY1-20 allele is a suppressor of the loss of the YPT1 gene, a ras-like gene implicated in vesicle translocation, suggesting that the two genes may interact with one another. Since Sec1p and beta-COP may also interact with small GTP-binding proteins of the ras superfamily, it is conceivable that the Rop and Ras2 gene products are not just co-expressed in common tissues, but may also functionally interact with one another in these tissues.
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Affiliation(s)
- A Salzberg
- Department of Biology, Technion-Israel Institute of Technology, Haifa
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Dillon P, Maurer H, Jenkins J, Krummel T, Parham D, Webber B, Salzberg A. A prospective study of nonrhabdomyosarcoma soft tissue sarcomas in the pediatric age group. J Pediatr Surg 1992; 27:241-4; discussion 244-5. [PMID: 1314309 DOI: 10.1016/0022-3468(92)90320-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nonrhabdomyosarcoma soft tissue sarcomas in infants and children are rare malignancies with most of the clinical data gained by retrospective analysis. In 1986, a prospective multicentered study was initiated by the Pediatric Oncology Group (POG) with a total of 75 cases now entered for epidemiologic examination. Median age of presentation was 12 years (range, newborn to 20 years). The male to female ratio was 2.3 to 1. The most common soft tissue tumor was synovial cell sarcoma (32/75, 42%), followed by fibrosarcoma (10/75, 13%), malignant fibrous histiocytoma (9/75, 12%), and malignant neurogenic tumors (8/75, 10%). Sixty-five percent of all tumors presented on the extremities (44% lower extremity, 21% upper extremity). Tumors of the trunk accounted for 28% (abdomen 15%, thorax 13%), whereas head and neck tumors were 7%. By TNMG classification, 16% presented as stage I, 21% as stage II, 33% as stage III, and 30% as stage IV. Age at presentation did not affect clinical site or stage. All upper extremity tumors presented with localized disease, whereas lower extremity tumors presented with regional nodal disease in 7% and metastatic disease (pulmonary) in 23% of the cases. Seventy-eight percent of the abdominal tumors were metastatic at diagnosis; the other 22% had extensive regional disease. In the thorax 78% had localized lesions with 22% having extensive regional disease. Ninety percent of synovial cell sarcomas were on the extremities: 84% localized disease and 12% metastatic spread at presentation. Sixty percent of the fibrosarcomas presented on the extremities with 80% having localized disease and 20% metastatic spread. Only 25% of the neurogenic tumors presented with localized disease, whereas 50% had metastases at the time of diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P Dillon
- Department of Pediatrics, Medical College of Virginia, Richmond
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Abstract
We report three additional cases of primary extrarenal Wilms' tumor and review those cases previously documented. Analysis of the location, histopathology, treatment, and survival of these cases supports the following conclusions: Wilms' tumor may occur in an extrarenal location without primary renal involvement and must be included in the differential diagnosis of abdominal, pelvic, and inguinal masses; an extrarenal location supports a more frequent occurrence of ectopic metanephric blastema than was previously recognized or origin of Wilms' tumor from a more primitive mesodermal tissue; and the natural history and prognosis of extrarenal and renal Wilms' tumors appears similar.
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Affiliation(s)
- B H Broecker
- Department of Surgery, Medical College of Virginia, Virginia Commonwealth University, Richmond
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Abstract
Large defects of the chest wall require stabilization of the remaining thorax to prevent paradoxical movement. A technique of fixation using rib grafts and compression plates is presented.
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Affiliation(s)
- J E Sherman
- Division of Plastic Surgery, Kriser Lung Center, Beth Israel Medical Center, New York, NY
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Cohen N, Salzberg A, Lev Z. A bidirectional promoter is regulating the Drosophila ras2 gene. Oncogene 1988; 3:137-42. [PMID: 3412773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We isolated and delimitated the Drosophila ras2 promoter region, determined its sequence and mapped the transcription units expressed in this region. The results showed that the Drosophila ras2 gene is flanked by another transcription unit, which codes for two larger transcripts, 2.5 and 2.9 kb long. Orientation experiments, in which sense and antisense RNA probes were used, revealed that both these and the ras2 transcripts are synthesized from different DNA strands. Thus, the flanking transcription unit is in the opposite polarity relative to the ras2 gene. The transcription start sites of the ras2 gene and the flanking transcription unit were determined by external primer extension with T4 DNA polymerase and by RNAase-protection assay and were found to be only 94 nucleotides apart. Apparently, the Drosophila ras2 promoter is a bidirectional promoter. Nucleotide sequence analysis revealed that the 5'-end of the ras2 transcript is within an inverted repeat of the insect cap box. TATA- and GC-like boxes were also found. Analysis of direct and inverted repeats in the promoter region suggested that it is asymmetrical. To demonstrate promoter activity, each side of the ras2 bidirectional promoter was fused to the bacterial chloramphenicol acetyltransferase (CAT) gene and tested by transfecting Drosophila Schneider 2 culture cells. Significant CAT activity was obtained with both transcription fusions.
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Affiliation(s)
- N Cohen
- Department of Biology, Technion-Israel Institute of Technology, Haifa
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Salzberg A, Ritz R. [Massive and small pulmonary embolisms in intensive care units]. Schweiz Med Wochenschr 1987; 117:1256-9. [PMID: 3672071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Over one fifth of patients hospitalized for massive pulmonary embolism die within the first few hours. The threatening load on the right ventricle can be reduced by early detection of embolism and immediate start to treatment. 53 patients treated for pulmonary embolism in our intensive care unit from 1982-1984 were divided into groups of 34 patients with massive embolism (occlusion 50% and/or circulatory shock) and 16 patients with small embolism. In 3 additional patients the embolism was detected only at autopsy. Patient's history and first clinical workup, together with special investigations and hemodynamics, allowed differentiation between massive and small embolism. Regarding treatment, patients with pulmonary embolism and circulatory shock were immediately embolectomized surgically. The other patients with massive embolism were treated by early fibrinolysis, with strict attention to any contraindications. These fibrinolyzed patients had fewer complications during the subsequent hospital course. A total of 8 patients with massive embolism and 2 patients with small embolism died during the same hospital stay. Where history and clinical findings prompt suspicion of massive pulmonary embolism a rather aggressive diagnostic procedure is indicated, since rapid reopening of the pulmonary circuit, to reduce the load on the right ventricle, may be life-saving.
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Affiliation(s)
- A Salzberg
- Abteilung Intensivmedizin, Kantonsspital Basel
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Abstract
This paper explores the use of fiberoptics in indirect laryngoscopy and encourages the speech pathologist to use this procedure in a diagnostic and therapeutic context. Routine use of this procedure by speech pathologists would broaden the role definition of the voice clinician as a skilled evaluator of vocal-fold pathologies.
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Chapey R, Lubinski R, Salzberg A, Chapey GD. The availability of language speech, and hearing services in day-care centers. ASHA 1978; 20:1030-3. [PMID: 743324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Raffa J, Kay S, Salzberg A. Large breast tumors of early adolescence. Va Med Mon (1918) 1969; 96:729-31. [PMID: 4317439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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