Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae

Background: Survival of Mycobacterium leprae, the causative bacteria for leprosy, in the human host is dependent to an extent on the ways in which its genome integrity is retained. DNA repair mechanisms protect bacterial DNA from damage induced by various stress factors. The current study is aimed a...

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Main Authors: Mukul Sharma, Sundeep Chaitanya Vedithi, Madhusmita Das, Anindya Roy, Mannam Ebenezer
Format: Article
Language:English
Published: Wolters Kluwer Medknow Publications 2017-01-01
Series:International Journal of Mycobacteriology
Subjects:
Online Access:http://www.ijmyco.org/article.asp?issn=2212-5531;year=2017;volume=6;issue=4;spage=365;epage=378;aulast=Sharma
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author Mukul Sharma
Sundeep Chaitanya Vedithi
Madhusmita Das
Anindya Roy
Mannam Ebenezer
author_facet Mukul Sharma
Sundeep Chaitanya Vedithi
Madhusmita Das
Anindya Roy
Mannam Ebenezer
author_sort Mukul Sharma
collection DOAJ
description Background: Survival of Mycobacterium leprae, the causative bacteria for leprosy, in the human host is dependent to an extent on the ways in which its genome integrity is retained. DNA repair mechanisms protect bacterial DNA from damage induced by various stress factors. The current study is aimed at understanding the sequence and functional annotation of DNA repair genes in M. leprae. Methods: T he genome of M. leprae was annotated using sequence alignment tools to identify DNA repair genes that have homologs in Mycobacterium tuberculosis and Escherichia coli. A set of 96 genes known to be involved in DNA repair mechanisms in E. coli and Mycobacteriaceae were chosen as a reference. Among these, 61 were identified in M. leprae based on sequence similarity and domain architecture. The 61 were classified into 36 characterized gene products (59%), 11 hypothetical proteins (18%), and 14 pseudogenes (23%). All these genes have homologs in M. tuberculosis and 49 (80.32%) in E. coli. A set of 12 genes which are absent in E. coli were present in M. leprae and in Mycobacteriaceae. These 61 genes were further investigated for their expression profiles in the whole transcriptome microarray data of M. leprae which was obtained from the signal intensities of 60bp probes, tiling the entire genome with 10bp overlaps. Results: It was noted that transcripts corresponding to all the 61 genes were identified in the transcriptome data with varying expression levels ranging from 0.18 to 2.47 fold (normalized with 16SrRNA). The mRNA expression levels of a representative set of seven genes ( four annotated and three hypothetical protein coding genes) were analyzed using quantitative Polymerase Chain Reaction (qPCR) assays with RNA extracted from skin biopsies of 10 newly diagnosed, untreated leprosy cases. It was noted that RNA expression levels were higher for genes involved in homologous recombination whereas the genes with a low level of expression are involved in the direct repair pathway. Conclusion: This study provided preliminary information on the potential DNA repair pathways that are extant in M. leprae and the associated genes.
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spelling doaj.art-ef0fa64886994321b77cc1dfb955475b2022-12-22T03:11:25ZengWolters Kluwer Medknow PublicationsInternational Journal of Mycobacteriology2212-55312212-554X2017-01-016436537810.4103/ijmy.ijmy_111_17Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium lepraeMukul SharmaSundeep Chaitanya VedithiMadhusmita DasAnindya RoyMannam EbenezerBackground: Survival of Mycobacterium leprae, the causative bacteria for leprosy, in the human host is dependent to an extent on the ways in which its genome integrity is retained. DNA repair mechanisms protect bacterial DNA from damage induced by various stress factors. The current study is aimed at understanding the sequence and functional annotation of DNA repair genes in M. leprae. Methods: T he genome of M. leprae was annotated using sequence alignment tools to identify DNA repair genes that have homologs in Mycobacterium tuberculosis and Escherichia coli. A set of 96 genes known to be involved in DNA repair mechanisms in E. coli and Mycobacteriaceae were chosen as a reference. Among these, 61 were identified in M. leprae based on sequence similarity and domain architecture. The 61 were classified into 36 characterized gene products (59%), 11 hypothetical proteins (18%), and 14 pseudogenes (23%). All these genes have homologs in M. tuberculosis and 49 (80.32%) in E. coli. A set of 12 genes which are absent in E. coli were present in M. leprae and in Mycobacteriaceae. These 61 genes were further investigated for their expression profiles in the whole transcriptome microarray data of M. leprae which was obtained from the signal intensities of 60bp probes, tiling the entire genome with 10bp overlaps. Results: It was noted that transcripts corresponding to all the 61 genes were identified in the transcriptome data with varying expression levels ranging from 0.18 to 2.47 fold (normalized with 16SrRNA). The mRNA expression levels of a representative set of seven genes ( four annotated and three hypothetical protein coding genes) were analyzed using quantitative Polymerase Chain Reaction (qPCR) assays with RNA extracted from skin biopsies of 10 newly diagnosed, untreated leprosy cases. It was noted that RNA expression levels were higher for genes involved in homologous recombination whereas the genes with a low level of expression are involved in the direct repair pathway. Conclusion: This study provided preliminary information on the potential DNA repair pathways that are extant in M. leprae and the associated genes.http://www.ijmyco.org/article.asp?issn=2212-5531;year=2017;volume=6;issue=4;spage=365;epage=378;aulast=SharmaDNA repairgene expressionhomologyMycobacterium leprae phylogenytranscriptome
spellingShingle Mukul Sharma
Sundeep Chaitanya Vedithi
Madhusmita Das
Anindya Roy
Mannam Ebenezer
Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
International Journal of Mycobacteriology
DNA repair
gene expression
homology
Mycobacterium leprae
phylogeny
transcriptome
title Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
title_full Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
title_fullStr Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
title_full_unstemmed Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
title_short Sequence homology and expression profile of genes associated with dna repair pathways in Mycobacterium leprae
title_sort sequence homology and expression profile of genes associated with dna repair pathways in mycobacterium leprae
topic DNA repair
gene expression
homology
Mycobacterium leprae
phylogeny
transcriptome
url http://www.ijmyco.org/article.asp?issn=2212-5531;year=2017;volume=6;issue=4;spage=365;epage=378;aulast=Sharma
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AT madhusmitadas sequencehomologyandexpressionprofileofgenesassociatedwithdnarepairpathwaysinmycobacteriumleprae
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