DOCSLIB.ORG

Conformational Trapping of Mismatch Recognition Complex MSH2/MSH3

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Conformational Trapping of Mismatch Recognition Complex MSH2/MSH3 Conformational trapping of Mismatch Recognition PNAS PLUS Complex MSH2/MSH3 on repair-resistant DNA loops Walter H. Langa,1,2, Julie E. Coatsb,1, Jerzy Majkaa, Greg L. Huraa, Yuyen Linb, Ivan Rasnikb,3, and Cynthia T. McMurraya,c,d,3 aLawrence Berkeley National Laboratory, Life Sciences Division, 1 Cyclotron Road, Berkeley, CA 94720; cDepartment of Molecular Pharmacology and Experimental Therapeutics; dDepartment of Biochemistry and Molecular Biology, Mayo Foundation, 200 First Street, Rochester, MN 55905; and bDepartment of Physics, Emory University, 400 Dowman Drive, MSC N214, Atlanta, GA 30322 Edited* by Peter H. von Hippel, Institute of Molecular Biology, Eugene, OR, and approved August 3, 2011 (received for review April 6, 2011) Insertion and deletion of small heteroduplex loops are common which fails to effectively couple DNA binding with downstream mutations in DNA, but why some loops are prone to mutation and repair signaling. We envision that conformational regulation of others are efficiently repaired is unknown. Here we report that the small loop repair occurs at the level of the junction dynamics. mismatch recognition complex, MSH2/MSH3, discriminates between a repair-competent and a repair-resistant loop by sensing the con- Results formational dynamics of their junctions. MSH2/MSH3 binds, bends, Conformational Integrity of MSH2/MSH3 and the DNA “Junction” Tem- and dissociates from repair-competent loops to signal downstream plates. We characterized the DNA-binding affinity and nucleotide repair. Repair-resistant Cytosine-Adenine-Guanine (CAG) loops adopt binding properties of MSH2/MSH3 bound to looped templates, a unique DNA junction that traps nucleotide-bound MSH2/MSH3, either a ðCAÞ4 loop or CAG hairpin loops of either 7 or 13 and inhibits its dissociation from the DNA. We envision that junction (ðCAGÞ7 and ðCAGÞ13) triplet repeats (Fig. 1A). Both loop and dynamics is an active participant and a conformational regulator hairpin templates were constructed from two single-stranded oli- of repair signaling, and governs whether a loop is removed by gonucleotides (Fig. 1A). Neither the ðCAÞ4 loop nor the CAG MSH2/MSH3 or escapes to become a precursor for mutation. stem had complementary sequences within the duplex portion of the template. Thus, the junction templates folded into stable DNA repair ∣ mismatch repair ∣ smFRET ∣ trinucelotide expansion extrahelical loops, which have been previously characterized in solution (26, 31). Folding of the CAG loops creates A/A mis- BIOCHEMISTRY nsertion or deletion of small extrahelical loops is one of the matches every third base pair in the stem, for a total of three ð Þ Imost common mutations in human cancers (1–3), but the me- mismatches in the CAG 7 template or a total of six mismatches chanism by which they occur is unknown. Small loops, bulges, in the ðCAGÞ13 template. DNA templates were analyzed by gel or kinked DNA occur frequently in DNA, and provide signals electrophoresis to (i) ensure the absence of any traces of single- for p53 recognition (4–7), recombination (8, 9), and/or most often stranded DNA and (ii) that the DNA loops were intact, as judged removal by the mismatch repair system (10–14). Two hetero- by an increase in the loop size and gel mobility (Fig. 1B). Unless dimeric mismatch recognition complexes, MSH2/MSH6 and specifically noted, all DNA templates were synthesized contain- MSH2/MSH3, operate in mammals with distinct, but overlapping ing a duplex base of 18 bases (Fig. 1A). specificities (12–14). The crystal structure (15–18), Atomic Force The purified human MSH2/MSH3 protein (hereafter referred Microscopy (AFM) (19), and single molecule fluorescence reso- to as MSH2/MSH3) was also of high quality (Fig. 1C). The full- nant energy transfer (smFRET) (19, 20) confirm that MSH2/ length MSH2/MSH3 was expressed and copurified as a hetero- MSH6 and Escherichia coli (MutS) preferentially bind single base dimer, and each subunit, when resolved by PAGE, migrated as a mismatches or two base pair bulges. MSH2/MSH3 can recognize single band according to the expected molecular mass (Fig. 1C). some base-base mismatches (21), but has a higher apparent affi- To further test the conformational integrity of the protein, we nity and specificity for small DNA loops composed of 2–13 bases visualized full-length MSH2/MSH3 using small angle X-ray scat- (12–14, 22–24). Thus, defects in repair mediated by MSH2/MSH3 tering (SAXS) (34, 35)(Fig. 1D). Interestingly, the high-resolu- are poised to be a major source of insertion-deletion mutations. tion SAXS structure revealed that the N-terminal portion of the The mechanism by which MSH2/MSH3 discriminates between MSH3 subunit formed an unfolded “panhandle” structure, which repair-competent and repair-resistant loops (24–26), however extended beyond the heterodimeric interface of MSH2/MSH3. remains enigmatic. A small ðCAÞ4 loop of DNA can be faithfully The handle undergoes a visible broadening and conformational repaired by MSH2/MSH3 both in vitro (24, 26) and in vivo (25, change upon binding the ðCAÞ4 loop. But otherwise, the DNA- 27, 28). In contrast, hydrogen bonded CAG hairpin loops are not bound heterodimeric portion of human MSH2/MSH3 was similar excised, and confer genomic instability through insertion and in conformation to that of the human MSH2/MSH6 bound to amplification of CAG repetitive tracts (29–31). Although ðCAÞ4 template containing a G-T mispaired base (16). Using these well loops and CAG hairpins both harbor three-way junctions, MSH2/ MSH3 interacts with them distinctly (24, 26). Why one template Author contributions: W.H.L., J.M., I.R., and C.T.M. designed research; W.H.L., J.E.C., J.M., is repaired better than the other is not known, but the conse- G.L.H., and Y.L. performed research; W.H.L., J.E.C., J.M., G.L.H., I.R., and C.T.M. analyzed quence is remarkable: Inefficient repair of CAG loops results in data; and W.H.L., J.M., I.R., and C.T.M. wrote the paper. mutations that underlie more than 20 hereditary neurodegenera- The authors declare no conflict of interest. tive or neuromuscular diseases (30–33). *This Direct Submission article had a prearranged editor. Here, we address the underlying basis for discriminating repair- Freely available online through the PNAS open access option. competent and repair-resistant DNA loops by MSH2/MSH3. We 1W.H.L. and J.E.C. contributed equally to this work. find that MSH2/MSH3 binds with similar affinity to a repair- 2 ’ ð Þ Present address: Department of Surgery, St. Jude Children s Research Hospital, 262 Danny competent CA 4 loop and to repair-resistant CAG hairpins. How- Thomas Place, MS 332, Memphis, TN 38105. ever, the three-way hairpin junction adopts a conformational state 3To whom correspondence may be addressed. E-mail: [email protected] or irasnik@ that traps nucleotide-bound MSH2/MSH3, and inhibits its disso- physics.emory.edu. ciation from the hairpin. The biochemical and smFRET results See Author Summary on page 17247. imply that repair-resistant CAG hairpins provide a unique but This article contains supporting information online at www.pnas.org/lookup/suppl/ nonproductive binding site for nucleotide-bound MSH2/MSH3, doi:10.1073/pnas.1105461108/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1105461108 PNAS ∣ October 18, 2011 ∣ vol. 108 ∣ no. 42 ∣ E837–E844 Downloaded by guest on September 30, 2021 nucleotide, the apparent affinity of MSH2/MSH3 for both the ðCAÞ4 loop and hairpin templates was in the low nanomolar range (Table 2), and was in good agreement with previous mea- surements (24, 26, 31). The presence of magnesium decreased the affinity of ATP-bound MSH2/MSH3 to any template by about 10-fold, but, in general, DNA binding of ADP- or ATP-bound MSH2/MSH3 did not distinguish repair-competent ðCAÞ4 loop from the repair-resistant ðCAGÞ7 hairpin or ðCAGÞ13 hairpin. MSH2/MSH3 Stabilizes a High FRET State When Bound to the Repair- ð Þ ð Þ Competent CA 4 Loop. The CA 4 loop differs structurally from the ðCAGÞ13 DNA in that the latter forms a hairpin comprising G-C hydrogen bonded base pairs and A/A mispaired bases every third nucleotide in the stem (24, 26). To test for conformation differences between the two templates, we measured the protein- induced DNA conformational dynamics using smFRET. We pre- pared DNA substrates, which were identical to those used in the Fig. 1. Conformational Integrity of Mismatch Recognition Complexes and biochemical DNA-binding experiments, except that the bottom DNA templates. (A) Schematic structure of the three-way junction DNA tem- strand of 18 nucleotides was labeled with Cy3 (on the 5′ end, ð Þ plates. The CA 4 loop and CAG hairpins are centrally located in the upper green ball) and Cy5 (on the 3′ end, red ball) (Fig. 2 A, C, E). Thus, unlabeled strand. The duplex base comprising eighteen base pairs, which for each template used in the smFRET experiments, the local ′ ′ were labeled at the 5 end with Cy3 and at the 5 end with Cy5 for smFRET environment of the fluorophores was identical. For both tem- experiments, or with a 5′ fluorescein for the FA experiments. (B) The purified ′ templates resolved on native polyacrylamide gels and visualized by ethidium plates, the top strand at the 3 end contains a poly-dT extension bromide staining. SS is the 18nuc single strand DNA that is the complemen- and a biotin tag for immobilization on streptavidin coated cover tary strand for the looped templates, DS is the 18 bp homoduplex DNA, and slips for observation (Fig. 2 A, C, E, blue ball). The extension the heteroduplex looped substrates are as labeled. (C) Resolution of purified was designed to prevent potential interaction of the fluorophores human MSH2/MSH3 (middle lane) and MSH2/MSH6 (right lane) proteins by with the streptavidin surface.
Load more

Recommended publications
  • Dihydrofolate Reductase Amplification and Sensitization to Methotrexate of Methotrexate-Resistant Colon Cancer Cells
    Published OnlineFirst February 3, 2009; DOI: 10.1158/1535-7163.MCT-08-0759 424 Dihydrofolate reductase amplification and sensitization to methotrexate of methotrexate-resistant colon cancer cells Cristina Morales,1 Maria J. Garcı´a,4 Maria Ribas,1 withdrawal and reexposure to MTX. Passive loss of the Rosa Miro´,2 Mar Mun˜oz,3 Carlos Caldas,4 DHFR amplicon by withdrawal of the drug results in MTX- and Miguel A. Peinado1,3 sensitive cells exhibiting a substantial reduction of their capacity or even an incapacity to generate resistance when 1Institut d’Investigacio´Biome`dica de Bellvitge, L’Hospitalet; submitted to a second cycle of MTX treatment. On a 2 Institut de Biotecnologia i Biomedicina, Departament de Biologia second round of drug administration, the resistant cells CelÁlular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, Bellaterra; 3Institut de Medicina Predictiva i generate a different amplicon structure, suggesting that the Personalitzada del Ca`ncer, Badalona, Barcelona, Spain and formation of the amplicon as in the first cycle of treatment 4Breast Cancer Functional Genomics Laboratory, Cancer is not feasible. These results indicate that DHFR gene Research UK Cambridge Research Institute and Department of amplification is a ‘‘wear and tear’’ process in HT29 cells Oncology, University of Cambridge, Li Ka Shing Centre, and that MTX-resistant cells may become responsive to a Cambridge, United Kingdom second round of treatment if left untreated during a sufficient period of time. [Mol Cancer Ther 2009; Abstract 8(2):424–32] Gene amplification is one of the most frequent manifes- tations of genomic instability in human tumors and plays an important role in tumor progression and acquisition of Introduction drug resistance.
    [Show full text]
  • Recruitment of Mismatch Repair Proteins to the Site of DNA Damage in Human Cells
    3146 Research Article Recruitment of mismatch repair proteins to the site of DNA damage in human cells Zehui Hong, Jie Jiang, Kazunari Hashiguchi, Mikiko Hoshi, Li Lan and Akira Yasui* Department of Molecular Genetics, Institute of Development, Aging and Cancer, Tohoku University, Seiryomachi 4-1, Aobaku, Sendai 980-8575, Japan *Author for correspondence (e-mail: [email protected]) Accepted 8 July 2008 Journal of Cell Science 121, 3146-3154 Published by The Company of Biologists 2008 doi:10.1242/jcs.026393 Summary Mismatch repair (MMR) proteins contribute to genome stability the PCNA-binding domain of MSH6. MSH2 is recruited to the by excising DNA mismatches introduced by DNA polymerase. DNA damage site through interactions with either MSH3 or Although MMR proteins are also known to influence cellular MSH6, and is required for recruitment of MLH1 to the damage responses to DNA damage, how MMR proteins respond to DNA site. We found, furthermore, that MutSβ is also recruited to damage within the cell remains unknown. Here, we show that UV-irradiated sites in nucleotide-excision-repair- and PCNA- MMR proteins are recruited immediately to the sites of various dependent manners. Thus, MMR and its proteins function not types of DNA damage in human cells. MMR proteins are only in replication but also in DNA repair. recruited to single-strand breaks in a poly(ADP-ribose)- dependent manner as well as to double-strand breaks. Using Supplementary material available online at mutant cells, RNA interference and expression of fluorescence- http://jcs.biologists.org/cgi/content/full/121/19/3146/DC1
    [Show full text]
  • Machine Learning-Based Approach Highlights the Use of a Genomic Variant Profile for Precision Medicine in Ovarian Failure
    Journal of Personalized Medicine Article Machine Learning-Based Approach Highlights the Use of a Genomic Variant Profile for Precision Medicine in Ovarian Failure Ismael Henarejos-Castillo 1,2 , Alejandro Aleman 1, Begoña Martinez-Montoro 3, Francisco Javier Gracia-Aznárez 4, Patricia Sebastian-Leon 1,3, Monica Romeu 5, Jose Remohi 2,6, Ana Patiño-Garcia 4,7 , Pedro Royo 3, Gorka Alkorta-Aranburu 4 and Patricia Diaz-Gimeno 1,3,* 1 IVI Foundation-Instituto de Investigación Sanitaria La Fe, Av. Fernando Abril Martorell 106, Torre A, Planta 1ª, 46026 Valencia, Spain; [email protected] (I.H.-C.); [email protected] (A.A.); [email protected] (P.S.-L.) 2 Department of Paediatrics, Obstetrics and Gynaecology, University of Valencia, Av. Blasco Ibáñez 15, 46010 Valencia, Spain; [email protected] 3 IVI-RMA Pamplona, Reproductive Medicine, C/Sangüesa, Número 15-Planta Baja, 31003 Pamplona, Spain; [email protected] (B.M.-M.); [email protected] (P.R.) 4 CIMA Lab Diagnostics, University of Navarra, IdiSNA, Avda Pio XII, 55, 31008 Pamplona, Spain; [email protected] (F.J.G.-A.); [email protected] (A.P.-G.); [email protected] (G.A.-A.) 5 Hospital Universitario y Politécnico La Fe, Av. Fernando Abril Martorell 106, 46026 Valencia, Spain; [email protected] 6 IVI-RMA Valencia, Reproductive Medicine, Plaça de la Policia Local, 3, 46015 Valencia, Spain 7 Laboratorio de Pediatría-Unidad de Genética Clínica, Clínica Universidad de Navarra, Avda Pio XII, 55, Citation: Henarejos-Castillo, I.; 31008 Pamplona, Spain Aleman, A.; Martinez-Montoro, B.; * Correspondence: [email protected] Gracia-Aznárez, F.J.; Sebastian-Leon, P.; Romeu, M.; Remohi, J.; Patiño- Abstract: Ovarian failure (OF) is a common cause of infertility usually diagnosed as idiopathic, Garcia, A.; Royo, P.; Alkorta-Aranburu, with genetic causes accounting for 10–25% of cases.
    [Show full text]
  • MSH3 Protein Expression and Nodal Status in MLH1-Deficient Colorectal Cancers Running Title
    Author Manuscript Published OnlineFirst on April 10, 2012; DOI: 10.1158/1078-0432.CCR-12-0175 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. Title: MSH3 Protein Expression and Nodal Status in MLH1-Deficient Colorectal Cancers Running Title: MSH3 status and Nodal Metastasis in MSI CRC Authors: Luigi Laghi 1,2, Paolo Bianchi 1, Gabriele Delconte 2, Giuseppe Celesti 1, Giuseppe Di Caro 1,3, Monica Pedroni 4, Anna Maria Chiaravalli 5, Barbara Jung 6, Carlo Capella 5, Maurizio Ponz de Leon 4, Alberto Malesci 2,7 Institutions: 1 Laboratory of Molecular Gastroenterology , IRCCS Istituto Clinico Humanitas Rozzano (Milan), Italy. 2 Department of Gastroenterology, IRCCS Istituto Clinico Humanitas - Rozzano (Milan), Italy. 3 PhD Program of the School in Pathology and Neuropathology - University of Milan, Italy. 4 Department of Internal Medicine, Medical Faculty, Modena and Reggio Emilia University, Modena, Italy. 5 Department of Human Morphology, Anatomic Pathology Unit, University of Insubria, Varese, Italy. 6 Division of Gastroenterology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA. 7 Department of Translational Medicine – University of Milan- Milan, Italy Addresses for correspondence: Dr.Luigi Laghi Prof. Alberto Malesci Dept. of Gastroenterology Dept. of Gastroenterology IRCCS Istituto Clinico Humanitas IRCCS Istituto Clinico Humanitas-University of Milan Via Manzoni, 56 Via Manzoni, 56 20089 Rozzano – Milan 20089 Rozzano - Milan ITALY ITALY e-mail: [email protected] e-mail: [email protected] phone: +39. 02. 8224. 4572 phone: +39. 02. 8224. 4542 fax: +39. 02. 8224. 4590 fax: +39. 02. 8224. 4590 Keywords: colorectal cancer, microsatellite instability, cancer genes, prognosis, biological markers 1 Downloaded from clincancerres.aacrjournals.org on September 25, 2021.
    [Show full text]
  • A Functional Assay for Mutations in Tumor Suppressor Genes Caused by Mismatch Repair Deficiency
    © 2001 Oxford University Press Human Molecular Genetics, 2001, Vol. 10, No. 24 2737–2743 A functional assay for mutations in tumor suppressor genes caused by mismatch repair deficiency Hanlee P. Ji and Mary-Claire King* Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, WA 98195-7720, USA Received May 25, 2001; Revised and Accepted September 19, 2001 The coding sequences of multiple human tumor MMR-deficient strains of S.cerevisiae has increased our suppressor genes include microsatellite sequences understanding of the role of MSI in human tumors (5–7). that are prone to mutations. Saccharomyces cerevisiae In cancers from individuals with HNPCC, the elevation in strains deficient in DNA mismatch repair (MMR) can mutation rates causes inactivation of specific tumor suppressor be used to determine de novo mutation rates of these gene, producing a selective growth advantage and thus human tumor suppressor genes as well as any other contributing to stepwise neoplastic progression (8). Multiple genes have been identified with microsatellite mutations gene sequence. Microsatellites in human TGFBR2, including TGFBR2, IGFR2, MSH3, MSH6, PTEN, BAX and PTEN and APC genes were placed in yeast vectors MBD4 (8–15). The majority of these microsatellites consist of and analyzed in isogenic yeast strains that were wild- mononucleotide repeats which accumulate 1 bp deletions or type or deletion mutants for MSH2 or MLH1. In MMR- insertions. deficient strains, the vector containing the (A)10 Observational studies have identified these microsatellite microsatellite sequence of TGFBR2 had a mutation mutation hotspots; candidate genes are sequenced for micro- rate (mutations/cell division) of 1.4 × 10–4, compared satellite mutations in a series of tumors and cell lines exhib- to a mutation rate of 1.7 × 10–6 in the wild-type strain.
    [Show full text]
  • Germline and Tumor Whole Genome Sequencing As a Diagnostic Tool to Resolve Suspected Lynch Syndrome
    medRxiv preprint doi: https://doi.org/10.1101/2020.03.12.20034991; this version posted March 17, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. Germline and Tumor Whole Genome Sequencing as a Diagnostic Tool to Resolve Suspected Lynch Syndrome Bernard J. Pope1,2,3, Mark Clendenning1,2, Christophe Rosty1,2,4,5, Khalid Mahmood1,2,3, Peter Georgeson1,2, Jihoon E. Joo1,2, Romy Walker1,2, Ryan A. Hutchinson1,2, Harindra Jayasekara1,2,6, Sharelle Joseland1,2, Julia Como1,2, Susan Preston1,2, Amanda B. Spurdle7, Finlay A. Macrae8,9,10, Aung K. Win11, John L. Hopper11, Mark A. Jenkins11, Ingrid M. Winship9,10, Daniel D. Buchanan1,2,10* 1 Colorectal Oncogenomics Group, Department of Clinical Pathology, The University of Melbourne, Parkville, Victoria, Australia 2 University of Melbourne Centre for Cancer Research, Victorian Comprehensive Cancer Centre, Parkville, Victoria, Australia 3 Melbourne Bioinformatics, The University of Melbourne, Parkville, Victoria, Australia 4 Envoi Pathology, Brisbane, Queensland, Australia 5 University of Queensland, School of Medicine, Herston, Queensland, Australia 6 Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia 7 Molecular Cancer Epidemiology Laboratory, QIMR Berghofer Medical Research Institute, Herston, Brisbane, Queensland, Australia 8 Colorectal Medicine and Genetics, The Royal Melbourne
    [Show full text]
  • Review DNA Mismatch Repair Genes and Colorectal Cancer
    148 Gut 2000;47:148–153 Review Gut: first published as 10.1136/gut.47.1.148 on 1 July 2000. Downloaded from DNA mismatch repair genes and colorectal cancer Summary hereditary component and the work of Warthin and Lynch Positional cloning and linkage analysis have shown that was seen as being anecdotal. However, by the 1980s many inactivation of one of the mismatch repair genes (hMLH1, reports of a “cancer family syndrome” were appearing in hMSH2, hPMS1, hPMS2, GTBP/hMSH6) is responsible the medical literature.56 Cancer family syndrome then for the microsatellite instability or replication error became subdivided into Lynch syndrome I (families with (RER+) seen in more than 90% of hereditary non- mainly colorectal cancers at an early age) and Lynch syn- polyposis colorectal cancers (HNPCC) and 15% of drome II (families with colorectal and extracolonic sporadic RER+ colorectal cancers. In HNPCC, a germline cancers, particularly of the female genital tract).7 All of this mutation (usually in hMLH1 or hMSH2) is accompanied diVerent terminology was eventually clarified with the by one further event (usually allelic loss) to inactivate a introduction of the term hereditary non-polyposis colorec- mismatch repair gene. In contrast, somatic mutations in tal cancer (HNPCC) to emphasise the lack of multiple the mismatch repair genes are not frequently found in spo- colonic polyps and to separate it from the polyposis radic RER+ colorectal cancers. Hypermethylation of the syndromes. hMLH1 promoter region has recently been described, and this epigenetic change is the predominant cause of Discovery of human mismatch repair genes inactivation of mismatch repair genes in sporadic RER+ Following the study of large kindreds using linkage analy- colorectal and other cancers.
    [Show full text]
  • MSH2 Gene Muts Homolog 2
    MSH2 gene mutS homolog 2 Normal Function The MSH2 gene provides instructions for making a protein that plays an essential role in repairing DNA. This protein helps fix errors that are made when DNA is copied (DNA replication) in preparation for cell division. The MSH2 protein joins with one of two other proteins, MSH6 or MSH3 (each produced from a different gene), to form a two-protein complex called a dimer. This complex identifies locations on the DNA where errors have been made during DNA replication. Another group of proteins, the MLH1-PMS2 dimer, then binds to the MSH2 dimer and repairs the errors by removing the mismatched DNA and replicating a new segment. The MSH2 gene is one of a set of genes known as the mismatch repair (MMR) genes. Health Conditions Related to Genetic Changes Constitutional mismatch repair deficiency syndrome About 10 mutations in the MSH2 gene have been associated with a condition called constitutional mismatch repair deficiency (CMMRD) syndrome. Individuals with this condition are at increased risk of developing cancers of the colon (large intestine) and rectum (collectively referred to as colorectal cancer), brain, and blood (leukemia or lymphoma). These cancers usually first occur in childhood, with the vast majority of cancers in CMMRD syndrome diagnosed in people under the age of 18. Many people with CMMRD syndrome also develop changes in skin coloring (pigmentation), similar to those that occur in a condition called neurofibromatosis type 1. Individuals with CMMRD syndrome inherit two MSH2 gene mutations, one from each parent, while people with Lynch syndrome (described below) have a mutation in one copy of the MSH2 gene.
    [Show full text]
  • Differential Regulation of Expression of the Mammalian DNA Repair Genes by Growth Stimulation
    Oncogene (2004) 23, 8581–8590 & 2004 Nature Publishing Group All rights reserved 0950-9232/04 $30.00 www.nature.com/onc Differential regulation of expression of the mammalian DNA repair genes by growth stimulation Ritsuko Iwanaga1, Hideyuki Komori1 and Kiyoshi Ohtani*,1 1Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan During DNA replication, DNA becomes more vulnerable did not change significantly during the cell cycle (Meyers to certain DNA damages. DNA repair genes involved in et al., 1997). However, previous finding that hMSH2 repair of the damages may be induced by growth protein was expressed in proliferating cells of the gut stimulation. However, regulation of DNA repair genes (Wilson et al., 1995) and recent findings that some of by growth stimulation has not been analysed in detail. In repair genes such as MSH2 and Rad51 were induced by this report, we analysed the regulation of expression of overexpression of the transcription factor E2F (Ishida mammalian MSH2, MSH3 and MLH1 genes involved in et al., 2001; Polager et al., 2002), which plays crucial mismatch repair, and Rad51 and Rad50 genes involved in roles in cell growth control, suggest that some of the homologous recombination repair, in relation to cell repair genes may be regulated by growth stimulation. In growth. Unexpectedly, we found a clear difference in spite of the expectation, the regulation of DNA repair regulation of these repair gene expression by growth genes by growth stimulation such as serum stimulation stimulation even in the same repair system. The expres- of quiescent fibroblasts has not been analysed in detail.
    [Show full text]
  • Functional Analysis of Human Mismatch Repair Gene Mutations Identifies Weak Alleles and Polymorphisms Capable of Polygenic Interactions
    Functional analysis of human mismatch repair gene mutations identifies weak alleles and polymorphisms capable of polygenic interactions Sandra L. Martinez and Richard D. Kolodner1 Ludwig Institute for Cancer Research, Departments of Medicine and Cellular and Molecular Medicine, and Moores-UCSD Cancer Center, UC San Diego School of Medicine, La Jolla, CA 92093-0669 Contributed by Richard D. Kolodner, January 22, 2010 (sent for review December 24, 2009) Many of the mutations reported as potentially causing Lynch morphisms in MSH2, MLH1, MSH6, and PMS2 (PMS1 in S. syndrome are missense mutations in human mismatch repair cerevisiae) and 14 reported missense mutations in these genes by (MMR) genes. Here, we used a Saccharomyces cerevisiae-based making equivalent mutations at the analogous position in the system to study polymorphisms and suspected missense mutations corresponding chromosomal gene in S. cerevisiae and evaluating in human MMR genes by modeling them at the appropriate S. their effect on MMR using mutator assays (Tables 1 and 2; S. cerevisiae chromosomal locus and determining their effect on cerevisiae allele designations are used in the text of this report). mutation rates. We identified a number of weak alleles of MMR Some of these variants have been characterized in other studies genes and MMR gene polymorphisms that are capable of interact- using S. cerevisiae-based assays (16–19, 23, 25) but mostly by ing with other weak alleles of MMR genes to produce strong poly- testing them as plasmid-borne mutations (16–19, 23)(Table 2). genic MMR defects. We also identified a number of alleles of MSH2 The mutator assays used include CAN1 gene inactivation that that act as if they inactivate the Msh2-Msh3 mispair recognition detects mutations inactivating the CAN1 gene and hom3-10 and complex thus causing weak MMR defects that interact with an lys2-10A frameshift reversions that detect mutations that revert msh6Δ mutation to result in complete MMR defects.
    [Show full text]
  • DNA Mismatch Repair Status Affects Cellular Response to Ara-C and Other Anti-Leukemic Nucleoside Analogs
    Letters to the Editor 1046 grants CA30969, CA29139, CA98543, CA98413, and CA114766 for unfavorable early treatment response. Blood 2009; 114: awarded to the Children’s Oncology Group. 1053–1062. 4 Gutierrez A, Sanda T, Grebliunaite R, Carracedo A, Salmena L, LYu1, ML Slovak2,5, K Mannoor1, C Chen1, SP Hunger3, Ahn Y et al. High frequency of PTEN, PI3K, and AKT abnormalities in T-cell acute lymphoblastic leukemia. Blood 2009; 114: AJ Carroll4, RA Schultz2, LG Shaffer2, BC Ballif2 and Y Ning1 1 647–650. Department of Pathology, University of Maryland School 5 Duker AL, Ballif BC, Bawle EV, Person RE, Mahadevan S, of Medicine, Baltimore, MD, USA; 2 Alliman S et al. Paternally inherited microdeletion at 15q11.2 Division of Cytogenetics, Signature Genomic Laboratories, confirms a significant role for the SNORD116 C/D box snoRNA Spokane, WA, USA; 3 cluster in Prader-Willi syndrome. Eur J Hum Genet 2010; 18: Center for Cancer and Blood Disorders, University of 1196–1201. Colorado Denver School of Medicine, Aurora, CO, USA and 6 Raschke S, Balz V, Efferth T, Schulz WA, Florl AR. Homozygous 4 Department of Genetics, University of Alabama at deletions of CDKN2A caused by alternative mechanisms in various Birmingham, Birmingham, AL, USA human cancer cell lines. Genes Chromosomes Cancer 2005; 42: E-mail: [email protected] 58–67. 5Current address: Division of Cytogenetics, Quest Diagnostics 7 De Keersmaecker K, Marynen P, Cools J. Genetic insights in the Nichols Institute, Chantilly, VA, USA. pathogenesis of T-cell acute lymphoblastic leukemia. Haemato- logica 2005; 90: 1116–1127. 8 Colaizzo-Anas T, Aplan PD.
    [Show full text]
  • Original Article MSH3 Rs26279 Polymorphism Increases Cancer Risk: a Meta-Analysis
    Int J Clin Exp Pathol 2015;8(9):11060-11067 www.ijcep.com /ISSN:1936-2625/IJCEP0014495 Original Article MSH3 rs26279 polymorphism increases cancer risk: a meta-analysis Hui-Kai Miao*, Li-Ping Chen, Dong-Ping Cai, Wei-Ju Kong, Li Xiao, Jie Lin* Department of Clinical Laboratory, The 101th Hospital of The People’s Liberation Army, Wuxi 214044, Jiangsu, China. *Equal contributors and co-first authors. Received August 14, 2015; Accepted August 18, 2015; Epub September 1, 2015; Published September 15, 2015 Abstract: Previous studies have investigated the association of mutS homolog 3 (MSH3) rs26279 G > A polymor- phism with the risk of different types of cancers including colorectal cancer, breast cancer, prostate cancer, blad- der cancer, thyroid cancer, ovarian cancer and oesophageal cancer. However, its association with cancer remains conflicting. We performed a comprehensive meta-analysis to derive a more precise estimation of the relationship between MSH3 rs26279 G > A polymorphism and cancer susceptibility. Systematically searching the PubMed and EMBASE databases yielded 11 publications with 12 studies of 3282 cases and 6476 controls. The strength of the association was determined by crude odds ratios (OR) and 95% confidence intervals (CI). Overall, pooled risk esti- mates demonstrated that MSH3 rs26279 G > A was significantly associated with an increased overall cancer risk under all the genetic models (GG vs. AA: OR = 1.27, 95% CI = 1.09-1.48, P = 0.002; AG vs. AA: OR = 1.10, 95% CI = 1.00-1.21, P = 0.045; GG vs. AG + AA: OR = 1.23, 95% CI = 1.06-1.42, P = 0.005; AG + GG vs.
    [Show full text]