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Sacconi L, Ueda HR, Pagès S, Silvestri L. Fluorescence tissue microscopy. Prog Biophys Mol Biol 2022; 168:1-2. [PMID: 34952029 DOI: 10.1016/j.pbiomolbio.2021.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Affiliation(s)
- L Sacconi
- European Laboratory for Non-linear Spectroscopy (LENS), Italy; National Institute of Optics, National Research Council, Italy; Faculty of Medicine, Institute for Experimental Cardiovascular Medicine, University of Freiburg, Freiburg in Breisgau, Germany.
| | - H R Ueda
- Department of Systems Pharmacology, The University of Tokyo, Japan; Laboratory for Synthetic Biology, RIKEN BDR, Japan
| | - S Pagès
- The Wyss Center for Bio and Neuroengineering, Geneva, Switzerland
| | - L Silvestri
- European Laboratory for Non-linear Spectroscopy (LENS), Italy; National Institute of Optics, National Research Council, Italy; Department of Physics and Astronomy, University of Florence, Italy
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2
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Duvic B, Jouan V, Essa N, Girard PA, Pagès S, Abi Khattar Z, Volkoff NA, Givaudan A, Destoumieux-Garzon D, Escoubas JM. Cecropins as a marker of Spodoptera frugiperda immunosuppression during entomopathogenic bacterial challenge. J Insect Physiol 2012; 58:881-888. [PMID: 22487443 DOI: 10.1016/j.jinsphys.2012.04.001] [Citation(s) in RCA: 20] [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] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 03/30/2012] [Accepted: 04/02/2012] [Indexed: 05/31/2023]
Abstract
An antimicrobial peptide (AMP) of the cecropin family was isolated by HPLC from plasma of the insect pest, Spodoptera frugiperda. Its molecular mass is 3910.9 Da as determined by mass spectrometry. Thanks to the EST database Spodobase, we were able to describe 13 cDNAs encoding six different cecropins which belong to the sub-families CecA, CecB, CecC and CecD. The purified peptide identified as CecB1 was chemically synthesized (syCecB1). It was shown to be active against Gram-positive and Gram-negative bacteria as well as fungi. Two closely related entomopathogenic bacteria, Xenorhabdus nematophila F1 and Xenorhabdus mauleonii VC01(T) showed different susceptibility to syCecB1. Indeed, X. nematophila was sensitive to syCecB1 whereas X. mauleonii had a minimal inhibitory concentration (MIC) eight times higher. Interestingly, injection of live X. nematophila into insects did not induce the expression of AMPs in hemolymph. This effect was not observed when this bacterium was heat-killed before injection. On the opposite, both live and heat-killed X. mauleonii induced the expression of AMPs in the hemolymph of S. frugiperda. The same phenomenon was observed for another immune-related protein lacking antimicrobial activity. Altogether, our data suggest that Xenorhabdus strains have developed different strategies to supplant the humoral defense mechanisms of S. frugiperda, either by increasing their resistance to AMPs or by preventing their expression during such host-pathogen interaction.
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Affiliation(s)
- B Duvic
- INRA, UMR1333, Laboratoire Diversité, Génomes et Interactions Microorganismes Insectes, Montpellier, France.
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3
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Therrien OD, Aubé B, Pagès S, Koninck PD, Côté D. Wide-field multiphoton imaging of cellular dynamics in thick tissue by temporal focusing and patterned illumination. Biomed Opt Express 2011; 2:696-704. [PMID: 21412473 PMCID: PMC3047373 DOI: 10.1364/boe.2.000696] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 02/15/2011] [Accepted: 02/15/2011] [Indexed: 05/21/2023]
Abstract
Wide-field temporal focusing is a novel technique that provides optical sectioning for imaging without the need for beam scanning. However, illuminating over large areas greatly reduces the photon density which limits the technique applicability to small regions, precluding functional imaging of cellular networks. Here we present a strategy that combines beam shaping and temporal focusing of amplified pulses (>1 µJ/pulse) for fast imaging of cells from the central nervous system in acute slices. Multiphoton video-rate imaging over total areas as wide as 4800 µm(2) with an optical sectioning under 10 µm at 800 nm is achieved with our setup, leading to imaging of calcium dynamics of multiple cells simultaneously in thick tissue.
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Affiliation(s)
- O. D. Therrien
- Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada
- Centre d'Optique Photonique et Laser (COPL), Université Laval, Québec, Qc, G1V 0A6, Canada
| | - B. Aubé
- Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada
- Centre d'Optique Photonique et Laser (COPL), Université Laval, Québec, Qc, G1V 0A6, Canada
| | - S. Pagès
- Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada
| | - P. De Koninck
- Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada
| | - D. Côté
- Centre de Recherche Université Laval Robert-Giffard (CRULRG), Université Laval, Québec, Qc, G1J 2G3, Canada
- Centre d'Optique Photonique et Laser (COPL), Université Laval, Québec, Qc, G1V 0A6, Canada
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Campos-Herrera R, Tailliez P, Pagès S, Ginibre N, Gutiérrez C, Boemare N. Characterization of Xenorhabdus isolates from La Rioja (Northern Spain) and virulence with and without their symbiotic entomopathogenic nematodes (Nematoda: Steinernematidae). J Invertebr Pathol 2009; 102:173-81. [DOI: 10.1016/j.jip.2009.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 07/16/2009] [Accepted: 08/07/2009] [Indexed: 11/16/2022]
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Abstract
Coevolution in mutualistic symbiosis can yield, because the interacting partners share common interests, to coadaptation: hosts perform better when associated with symbionts of their own locality than with others coming from more distant places. However, as the two partners of a symbiosis might also experience conflicts over part of their life cycle, coadaptation might not occur for all life-history traits. We investigated this issue in symbiotic systems where nematodes (Steinernema) and bacteria (Xenorhabdus) reproduce in insects they have both contributed to kill. Newborn infective juveniles (IJs) that carry bacteria in their intestine then disperse from the insect cadaver in search of a new host to infect. We ran experiments where nematodes coinfect insects with bacteria that differ from their native symbiont. In both Steinernema carpocapsae/Xenorhabdus nematophila and Steinernema feltiae/Xenorhabdus bovienii symbioses, we detected an overall specificity which favours the hypothesis of a fine-tuned co-adaptation process. However, we also found that the life-history traits involved in specificity strongly differ between the two model systems: when associated with strains that differ too much from their native symbionts, S. carpocapsae has low parasitic success, whereas S. feltiae has low survival in dispersal stage.
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Affiliation(s)
- E Chapuis
- Institut des Sciences de l'Evolution de Montpellier, UMR CNRS 5554, Université Montpellier 2, F-34095 Montpellier Cedex 05, France
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Sicard M, Ferdy JB, Pagès S, Le Brun N, Godelle B, Boemare N, Moulia C. When mutualists are pathogens: an experimental study of the symbioses between Steinernema (entomopathogenic nematodes) and Xenorhabdus (bacteria). J Evol Biol 2004; 17:985-93. [PMID: 15312071 DOI: 10.1111/j.1420-9101.2004.00748.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [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: 12/01/2022]
Abstract
In this paper, we investigate the level of specialization of the symbiotic association between an entomopathogenic nematode (Steinernema carpocapsae) and its mutualistic native bacterium (Xenorhabdus nematophila). We made experimental combinations on an insect host where nematodes were associated with non-native symbionts belonging to the same species as the native symbiont, to the same genus or even to a different genus of bacteria. All non-native strains are mutualistically associated with congeneric entomopathogenic nematode species in nature. We show that some of the non-native bacterial strains are pathogenic for S. carpocapsae. When the phylogenetic relationships between the bacterial strains was evaluated, we found a clear negative correlation between the effect a bacterium has on nematode fitness and its phylogenetic distance to the native bacteria of this nematode. Moreover, only symbionts that were phylogenetically closely related to the native bacterial strain were transmitted. These results suggest that co-evolution between the partners has led to a high level of specialization in this mutualism, which effectively prevents horizontal transmission. The pathogenicity of some non-native bacterial strains against S. carpocapsae could result from the incapacity of the nematode to resist specific virulence factors produced by these bacteria.
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Affiliation(s)
- M Sicard
- Laboratoire Génome, Populations, Interactions, Adaptation, Université de Montpellier II, Montpellier, France.
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Record E, Asther M, Sigoillot C, Pagès S, Punt PJ, Delattre M, Haon M, van den Hondel CAMJJ, Sigoillot JC, Lesage-Meessen L, Asther M. Overproduction of the Aspergillus niger feruloyl esterase for pulp bleaching application. Appl Microbiol Biotechnol 2003; 62:349-55. [PMID: 12743752 DOI: 10.1007/s00253-003-1325-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2002] [Revised: 03/13/2003] [Accepted: 03/13/2003] [Indexed: 11/27/2022]
Abstract
A well-known industrial fungus for enzyme production, Aspergillus niger, was selected to produce the feruloyl esterase FAEA by homologous overexpression for pulp bleaching application. The gpd gene promoter was used to drive FAEA expression. Changing the nature and concentration of the carbon source nature (maltose to glucose; from 2.5 to 60 g l(-1)), improved FAEA activity 24.5-fold and a yield of 1 g l(-1) of the corresponding protein in the culture medium was achieved. The secreted FAEA was purified 3.5-fold to homogeneity in a two-step purification procedure with a recovery of 69%. The overproduced protein was characterised and presented properties in good agreement with those of native FAEA. The recombinant FAEA was tested for wheat straw pulp bleaching, with or without a laccase mediator system and xylanase. Best results were obtained using a bi-sequential process with a sequence including xylanase, FAEA and laccase, and yielded very efficient delignification--close to 75%--and a kappa number of 3.9. This is the first report on the potential application of recombinant FAEA in the pulp and paper sector.
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Affiliation(s)
- E Record
- UMR 1163 INRA/Université de Provence de Biotechnologie des Champignons Filamenteux, IFR-BAIM, Universités de Provence et de la Méditerranée, ESIL, 163 avenue de Luminy, Case Postale 925, 13288, Marseille Cedex 09, France.
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Shimon LJ, Pagès S, Belaich A, Belaich JP, Bayer EA, Lamed R, Shoham Y, Frolow F. Structure of a family IIIa scaffoldin CBD from the cellulosome of Clostridium cellulolyticum at 2.2 A resolution. Acta Crystallogr D Biol Crystallogr 2000; 56:1560-8. [PMID: 11092922 DOI: 10.1107/s0907444900012889] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2000] [Accepted: 09/19/2000] [Indexed: 11/10/2022]
Abstract
The crystal structure of the family IIIa cellulose-binding domain (CBD) from the cellulosomal scaffoldin subunit (CipC) of Clostridium cellulolyticum has been determined. The structure reveals a nine-stranded jelly-roll topology which exhibits distinctive structural elements consistent with family III CBDs that bind crystalline cellulose. These include a well conserved calcium-binding site, a putative cellulose-binding surface and a conserved shallow groove of unknown function. The CipC CBD structure is very similar to the previously elucidated family IIIa CBD from the CipA scaffoldin of C. thermocellum, with some minor differences. The CipC CBD structure was also compared with other previously described CBD structures from families IIIc and IV derived from the endoglucanases of Thermomonospora fusca and Cellulomonas fimi, respectively. The possible functional consequences of structural similarities and differences in the shallow groove and cellulose-binding faces among various CBD families and subfamilies are discussed.
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Affiliation(s)
- L J Shimon
- Faculty of Chemistry, The Weizmann Institute of Science, Rehovot, Israel.
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Pagès S, Heijne WH, Kester HC, Visser J, Benen JA. Subsite mapping of Aspergillus niger endopolygalacturonase II by site-directed mutagenesis. J Biol Chem 2000; 275:29348-53. [PMID: 10893426 DOI: 10.1074/jbc.m910112199] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [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: 11/06/2022] Open
Abstract
To assess the subsites involved in substrate binding in Aspergillus niger endopolygalacturonase II, residues located in the potential substrate binding cleft stretching along the enzyme from the N to the C terminus were subjected to site-directed mutagenesis. Mutant enzymes were characterized with respect to their kinetic parameters using polygalacturonate as a substrate and with respect to their mode of action using oligogalacturonates of defined length (n = 3-6). In addition, the effect of the mutations on the hydrolysis of pectins with various degrees of esterification was studied. Based on the results obtained with enzymes N186E and D282K it was established that the substrate binds with the nonreducing end toward the N terminus of the enzyme. Asn(186) is located at subsite -4, and Asp(282) is located at subsite +2. The mutations D183N and M150Q, both located at subsite -2, affected catalysis, probably mediated via the sugar residue bound at subsite -1. Tyr(291), located at subsite +1 and strictly conserved among endopolygalacturonases appeared indispensable for effective catalysis. The mutations E252A and Q288E, both located at subsite +2, showed only slight effects on catalysis and mode of action. Tyr(326) is probably located at the imaginary subsite +3. The mutation Y326L affected the stability of the enzyme. For mutant E252A, an increased affinity for partially methylesterified substrates was recorded. Enzyme N186E displayed the opposite behavior; the specificity for completely demethylesterified regions of substrate, already high for the native enzyme, was increased. The origin of the effects of the mutations is discussed.
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Affiliation(s)
- S Pagès
- Section of Molecular Genetics of Industrial Micro-Organisms, Wageningen University, Dreyenlaan 2, 6703 HA Wageningen, The Netherlands
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Wagner T, Stoppa-Lyonnet D, Fleischmann E, Muhr D, Pagès S, Sandberg T, Caux V, Moeslinger R, Langbauer G, Borg A, Oefner P. Denaturing high-performance liquid chromatography detects reliably BRCA1 and BRCA2 mutations. Genomics 1999; 62:369-76. [PMID: 10644434 DOI: 10.1006/geno.1999.6026] [Citation(s) in RCA: 171] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Denaturing high-performance liquid chromatography (DHPLC) is a recently developed method of comparative sequencing based upon heteroduplex detection. To assess the reliability of this method, 180 different mutations (54 deletions, 12 insertions, and 117 single base substitutions) in BRCA1 and BRCA2 were tested. Second, 25 index individuals with complete DHPLC analysis of BRCA1 were reanalyzed by dye-terminator sequencing. Third, 41 index individuals were analyzed concomitantly by both DGGE and DHPLC. Of the 180 different BRCA1 and BRCA2 mutations, 179 showed heterozygous DHPLC elution profiles. Dye-terminator sequencing of the entire BRCA1 gene, including 5592 bp of coding sequence and 5206 bp of flanking noncoding sequence, in 25 index individuals did not reveal additional variants missed by DHPLC. The concomitant analysis of 41 index cases showed that 4 probably disease-associated mutations were identified by DHPLC while only 3 of those 4 sites were detected by denaturing gradient gel electrophoresis. We conclude that DHPLC is a sensitive and cost-effective method for the screening of BRCA1 and BRCA2.
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Affiliation(s)
- T Wagner
- Division of Senology, University of Vienna, Vienna, 1090, Austria
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Abstract
The recent identification of the BRCA1 and BRCA2 genes has improved our understanding of the association between breast and ovarian cancers in certain families. Carriers of predisposing germline mutations must decide on different options for management, including close follow-up or prophylactic surgery. Further studies are needed to elucidate the optimal management of these patients and to identify the factors that modify their risk for developing breast cancer. Finally, we must work to prevent any form of discrimination against those who, following genetic testing, are found to be at increased risk for breast cancer.
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Fierobe HP, Pagès S, Bélaïch A, Champ S, Lexa D, Bélaïch JP. Cellulosome from Clostridium cellulolyticum: molecular study of the Dockerin/Cohesin interaction. Biochemistry 1999; 38:12822-32. [PMID: 10504252 DOI: 10.1021/bi9911740] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [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: 11/28/2022]
Abstract
Clostridium cellulolyticum produces cellulolytic complexes (cellulosomes) made of 10-13 cell wall degrading enzymes tightly bound to a scaffolding protein (CipC) by means of their dockerin domain. It has previously been shown that the receptor domains in CipC are the cohesin domains and that the cohesin/dockerin interaction is calcium-dependent. In the present study, surface plasmon resonance was used to demonstrate that the free cohesin1 from CipC and dockerin from CelA have the same K(D) (2.5 x 10(-)(10) M) as that of the entire CelA and a larger fragment of CipC, the latter of which contains, in addition to cohesin1, a cellulose binding domain and a hydrophilic domain of unknown function. This demonstrates that neither the catalytic domain of CelA nor the noncohesin domains of CipC have any influence on the interaction. Dockerin domains are composed of two conserved segments of 22 residues: removal of the second segment abolishes the affinity for cohesin1, whereas modified dockerins having twice the first segment, twice the second, or both segments but in a reverse order have K(D) values for cohesin1 in the same range as that observed for wild-type dockerin. These data indicate that if two segments are required for the complexation with the cohesin, segments 1 and 2 are similar enough to replace each other. Calcium overlay experiments revealed that the dockerin domain has one calcium binding site per conserved segment. Circular dichroism performed on wild-type and mutant dockerins indicates that this domain is well structured and that removal of calcium only weakly affects the secondary structure, which remains 40-45% helical.
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Affiliation(s)
- H P Fierobe
- Laboratoire de Bioénergétique et Ingénierie des Protéines, Centre National de la Recherche Scientifique, 31, Chemin Joseph-Aiguier, F-13402 Marseille, France.
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Pagès S, Bélaïch A, Fierobe HP, Tardif C, Gaudin C, Bélaïch JP. Sequence analysis of scaffolding protein CipC and ORFXp, a new cohesin-containing protein in Clostridium cellulolyticum: comparison of various cohesin domains and subcellular localization of ORFXp. J Bacteriol 1999; 181:1801-10. [PMID: 10074072 PMCID: PMC93578 DOI: 10.1128/jb.181.6.1801-1810.1999] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.8] [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] Open
Abstract
The gene encoding the scaffolding protein of the cellulosome from Clostridium cellulolyticum, whose partial sequence was published earlier (S. Pagès, A. Bélaïch, C. Tardif, C. Reverbel-Leroy, C. Gaudin, and J.-P. Bélaïch, J. Bacteriol. 178:2279-2286, 1996; C. Reverbel-Leroy, A. Bélaïch, A. Bernadac, C. Gaudin, J. P. Bélaïch, and C. Tardif, Microbiology 142:1013-1023, 1996), was completely sequenced. The corresponding protein, CipC, is composed of a cellulose binding domain at the N terminus followed by one hydrophilic domain (HD1), seven highly homologous cohesin domains (cohesin domains 1 to 7), a second hydrophilic domain, and a final cohesin domain (cohesin domain 8) which is only 57 to 60% identical to the seven other cohesin domains. In addition, a second gene located 8.89 kb downstream of cipC was found to encode a three-domain protein, called ORFXp, which includes a cohesin domain. By using antiserum raised against the latter, it was observed that ORFXp is associated with the membrane of C. cellulolyticum and is not detected in the cellulosome fraction. Western blot and BIAcore experiments indicate that cohesin domains 1 and 8 from CipC recognize the same dockerins and have similar affinity for CelA (Ka = 4.8 x 10(9) M-1) whereas the cohesin from ORFXp, although it is also able to bind all cellulosome components containing a dockerin, has a 19-fold lower Ka for CelA (2.6 x 10(8) M-1). Taken together, these data suggest that ORFXp may play a role in cellulosome assembly.
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Affiliation(s)
- S Pagès
- Bioénergétique et Ingéniérie des Protéines, Centre National de la Recherche Scientifique, Marseilles, France
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Puget N, Stoppa-Lyonnet D, Sinilnikova OM, Pagès S, Lynch HT, Lenoir GM, Mazoyer S. Screening for germ-line rearrangements and regulatory mutations in BRCA1 led to the identification of four new deletions. Cancer Res 1999; 59:455-61. [PMID: 9927062] [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: 02/10/2023]
Abstract
Most previous BRCA1 mutation screening studies conducted on breast cancer families were aimed at identifying mutations in the coding sequence and splice sites. Mutations in the promoter and untranslated regions, and large rearrangements are missed by standard mutation detection strategies. To look specifically for such germ-line mutations in the BRCA1 gene, we have analyzed a series of 27 American and 51 French breast cancer families in which no BRCA1 mutation was identified by classical techniques. No mutations were detected in either the promoter or untranslated regions, and we did not find any deletion of the whole gene. Four families were found to carry distinct deletions. Two of them, probably generated by Alu-mediated homologous recombination, were internal deletions of 3 and 23.8 kb, encompassing exon 15 and exons 8-13, respectively. These alterations both lead to a frameshift in the mutant mRNA and to premature stop codon-mediated mRNA decay. The other two deletions encompass exons 1 and 2. On the basis of previous and present analyses, rearrangements represent 8% (3/37) of all mutations in our set of BRCA1 American families. Consequently, the search for rearrangements appears mandatory in BRCA1 mutation screening studies.
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Affiliation(s)
- N Puget
- International Agency for Research on Cancer, Lyon, France
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Puget N, Sinilnikova OM, Stoppa-Lyonnet D, Audoynaud C, Pagès S, Lynch HT, Goldgar D, Lenoir GM, Mazoyer S. An Alu-mediated 6-kb duplication in the BRCA1 gene: a new founder mutation? Am J Hum Genet 1999; 64:300-2. [PMID: 9915971 PMCID: PMC1377730 DOI: 10.1086/302211] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Essioux L, Girodet C, Sinilnikova O, Pagès S, Eisinger F, de Résende S, Maugard C, Lanoë D, Longy M, Bignon YJ, Sobol H, Bonaïti-Pellié C, Stoppa-Lyonnet D. Marker segregation information in breast/ovarian cancer genetic counseling: is it still useful? Groupe Génétique et Cancer de la Fédération Nationale des Centres de Lutte Contre le Cancer. Am J Med Genet 1998; 79:175-83. [PMID: 9788557 DOI: 10.1002/(sici)1096-8628(19980923)79:3<175::aid-ajmg5>3.0.co;2-m] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The use of mutation screening of BRCA1 and BRCA2 genes as a genetic test is still to a certain extent limited and the oncogeneticist may want to use complementary approaches to identify at-risk individuals. In a series of 23 families with at least three breast or ovarian cancer cases, screened for mutations at BRCA1 and BRCA2 and typed for markers at both loci, we investigated the usefulness of marker segregation information at two levels: 1) to what extent can the indirect approach identify the mutation carrier status of screened cases and their first-degree relatives, and 2) in what way does it help to identify the gene implicated in a family in which neither BRCA1 nor BRCA2 mutation has been detected? Using the indirect approach, the carrier status of the screened case could be determined with quasi certainty in three families and with a high probability in eight families. This status could be inferred in unaffected first-degree relatives as almost certain in one family and as highly probable in six families. Fourteen mutations were found concurrently in our series. Among the nine mutation-negative families, we were able to conclude that a BRCA1 mutation most probably segregated in one and that a mutation other than BRCA1 and BRCA2 was probably involved in two families. Our results show that, in small families, little help is to be expected from linkage data and mutation screening is the only way of identifying the origin of a genetic predisposition in a family. Marker segregation information may be useful in some large breast/ovarian cancer families in which no BRCA1 or BRCA2 mutation has been detected.
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Affiliation(s)
- L Essioux
- Unité de Recherches en Epidémiologie des Cancers/INSERM U351, Institut Gustave Roussy, Villejuif, France
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Pagès S, Bélaïch A, Bélaïch JP, Morag E, Lamed R, Shoham Y, Bayer EA. Species-specificity of the cohesin-dockerin interaction between Clostridium thermocellum and Clostridium cellulolyticum: prediction of specificity determinants of the dockerin domain. Proteins 1997; 29:517-27. [PMID: 9408948] [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: 02/05/2023]
Abstract
The cross-species specificity of the cohesin-dockerin interaction, which defines the incorporation of the enzymatic subunits into the cellulosome complex, has been investigated. Cohesin-containing segments from the cellulosomes of two different species, Clostridium thermocellum and Clostridium cellulolyticum, were allowed to interact with cellulosomal (dockerin-containing) enzymes from each species. In both cases, the cohesin domain of one bacterium interacted with enzymes from its own cellulosome in a calcium-dependent manner, but the same cohesin failed to recognize enzymes from the other species. Thus, in the case of these two bacteria, the cohesin-dockerin interaction seems to be species-specific. Based on intra- and cross-species sequence comparisons among the different dockerins together with their known specificities, we tender a prediction as to the amino-acid residues critical to recognition of the cohesins. The suspected residues were narrowed down to only four, which comprise a repeated pair located within the calcium-binding motif of two duplicated sequences, characteristic of the dockerin domain. According to the proposed model, these four residues do not participate in the binding of calcium per se; instead, they appear to serve as recognition codes in promoting interaction with the cohesin surface.
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Affiliation(s)
- S Pagès
- Centre National de la Recherche Scientifique, IBSM-IFR1, Marseille, France
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Stoppa-Lyonnet D, Laurent-Puig P, Essioux L, Pagès S, Ithier G, Ligot L, Fourquet A, Salmon RJ, Clough KB, Pouillart P, Bonaïti-Pellié C, Thomas G. BRCA1 sequence variations in 160 individuals referred to a breast/ovarian family cancer clinic. Institut Curie Breast Cancer Group. Am J Hum Genet 1997; 60:1021-30. [PMID: 9150149 PMCID: PMC1712430] [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: 02/04/2023] Open
Abstract
An account of familial aggregation in breast/ovarian cancer has become possible with the identification of BRCA1 germ-line mutations. We evaluated, for 249 individuals registered with the Institut Curie in Paris, the prior probability that an individual carried a mutation that predisposes to these diseases. We chose 160 women for BRCA1 analysis: 103 with a family history of breast cancer and 57 with a family history of breast-ovarian cancer. To detect small mutations, we generated and analyzed 35 overlapping genomic PCR products that cover the coding portion of the gene, by using denaturing gradient gel electrophoresis. Thirty-eight truncating mutations (32 frameshifts, 4 nonsense mutations, and 2 splice variants) were observed in 15% of women with a family history of breast cancer only and in 40% of those with a history of breast-ovarian cancer. Twelve of 25 distinct truncating mutations identified were novel and unique. Most BRCA1 mutations that had been reported more than five times in the Breast Cancer Information Core were present in our series. One mutation (5149del4) observed in two apparently unrelated families most likely originates from a common ancestor. The position of truncating mutations did not significantly affect the ratio of the risk of breast cancer to that of ovarian cancer. In addition, 15 DNA variants (14 missense mutations and 1 neutral mutation) were identified, 9 of which were novel. Indirect evidence suggests that seven of these mutations are deleterious.
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Affiliation(s)
- D Stoppa-Lyonnet
- Unité de Génétique Oncologique and Unité INSERM U 434, Paris, France.
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Abstract
The role of a miniscaffolding protein, miniCipC1, forming part of Clostridium cellulolyticum scaffolding protein CipC in insoluble cellulose degradation was investigated. The parameters of the binding of miniCipC1, which contains a family III cellulose-binding domain (CBD), a hydrophilic domain, and a cohesin domain, to four insoluble celluloses were determined. At saturating concentrations, about 8.2 micromol of protein was bound per g of bacterial microcrystalline cellulose, while Avicel, colloidal Avicel, and phosphoric acid-swollen cellulose bound 0.28, 0.38, and 0.55 micromol of miniCipC1 per g, respectively. The dissociation constants measured varied between 1.3 x 10(-7) and 1.5 x 10(-8) M. These results are discussed with regard to the properties of the various substrates. The synergistic action of miniCipC1 and two forms of endoglucanase CelA (with and without the dockerin domain [CelA2 and CelA3, respectively]) in cellulose degradation was also studied. Although only CelA2 interacted with miniCipC1 (K(d), 7 x 10(-9) M), nonhydrolytic miniCipC1 enhanced the activities of endoglucanases CelA2 and CelA3 with all of the insoluble substrates tested. This finding shows that miniCipC1 plays two roles: it increases the enzyme concentration on the cellulose surface and enhances the accessibility of the enzyme to the substrate by modifying the structure of the cellulose, leading to an increased available cellulose surface area. In addition, the data obtained with a hybrid protein, CelA3-CBD(CipC), which was more active towards all of the insoluble substrates tested confirm that the CBD of the scaffolding protein plays an essential role in cellulose degradation.
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Affiliation(s)
- S Pagès
- Bioénérgetique et Ingéniérie des Protéines, Centre National de la Recherche Scientifique, IBSM-IFR1, Marseille, France
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Pagès S, Belaich A, Tardif C, Reverbel-Leroy C, Gaudin C, Belaich JP. Interaction between the endoglucanase CelA and the scaffolding protein CipC of the Clostridium cellulolyticum cellulosome. J Bacteriol 1996; 178:2279-86. [PMID: 8636029 PMCID: PMC177936 DOI: 10.1128/jb.178.8.2279-2286.1996] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [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: 02/01/2023] Open
Abstract
The 5' end of the cipC gene, coding for the N-terminal part of CipC, the scaffolding protein of Clostridium cellulolyticum ATCC 35319, was cloned and sequenced. It encodes a 586-amino-acid peptide, including several domains: a cellulose-binding domain, a hydrophilic domain, and two hydrophobic domains (cohesin domains). Sequence alignments showed that the N terminus of CipC and CbpA of C. cellulovorans ATCC 35296 have the same organization. The mini-CipC polypeptide, containing a cellulose-binding domain, hydrophilic domain 1, and cohesin domain 1, was overexpressed in Escherichia coli and purified. The interaction between endoglucanase CelA, with (CelA2) and without (CelA3) the characteristic clostridial C-terminal domain called the duplicated-segment or dockerin domain, and the mini-CipC polypeptide was monitored by two different methods: the interaction Western blotting (immunoblotting) method and binding assays with biotin-labeled protein. Among the various forms of CelA (CelA2, CelA3, and an intermediary form containing only part of the duplicated segment), only CelA2 was found to interact with cohesin domain 1 of CipC. The apparent equilibrium dissociation constant of the CelA2-mini-CipC complex was 7 x 10(-9)M, which indicates that there exists a high affinity between these two proteins.
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Affiliation(s)
- S Pagès
- Bioénergétique et Ingéniéri des protéines, Centre National de la Recherche Scientifique, Marseille, France
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