Mapping Of Transcriptional Start Site And The Identification Of Novel sRNA In Mycobacterium Tuberculosis H37Rv

Lee, Li Pin (2016) Mapping Of Transcriptional Start Site And The Identification Of Novel sRNA In Mycobacterium Tuberculosis H37Rv. PhD thesis, Universiti Sains Malaysia.

[img]
Preview
PDF
Download (800Kb) | Preview

    Abstract

    Penyesuaian Mycobacterium tuberculosis (Mtb) terhadap pelbagai perubahan persekitaran dalam sistem imun membolehkan bakteria tersebut untuk hidup berterusan dalam individu yang dijangkiti selama beberapa dekad. Pelbagai aspek dalam pengawalan ekspresi gen terhadap perubahan tekanan persekitaran telah dikaji secara meluas dalam Mtb. Namun, tidak banyak perhatian yang diberi terhadap fungsi pengawalan ekspresi gen oleh titik awal transkripsi (TSSs) dan RNA kecil (sRNAs) dalam Mtb, terutamanya dalam pelbagai rangsangan tekanan persekitaran. Ini menginspirasikan usaha dalam pengenalpastian TSSs dan sRNAs yang terlibat dalam pelbagai rangsangan tekanan persekitaran. Untuk mengenal pasti TSSs dalam Mtb, perpustakaan cDNA yang diperkaya dengan transkrip utama telah dibina untuk RNA sequencing, dan TSSpredator telah diguna untuk menganalisis TSSs bagi Mtb dalam pelbagai rangsangan tekanan persekitaran. Sebanyak 8,173 TSSs telah dikenal pasti dalam enam keadaan. Kebanyakan TSSs (3,904) terletak dalam gen (TSS dalaman) dan 1,932 TSSs primer yang terletak dalam lingkungan 300 nt daripada titik permulaan translasi. 2,861 TSSs merupakan permulaan bagi sRNAs antisense yang berpotensi (TSS antisense). Selain itu, 215 TSSs yang terletak dalam kawasan intergen merupakan permulaan yang berpotensi bagi sRNA berkod trans. The adaptability of Mycobacterium tuberculosis (Mtb) to various environmental changes presented by host immune systems enables its persistence within infected hosts for decades. Various aspects of gene expression regulation in response to environmental stress have been extensively analyzed in Mtb. However, the roles of transcriptional start sites (TSSs) and the small regulatory RNAs (sRNAs) in regulating gene expression within Mtb are given very little attention, particularly under stress condition. This ignites the effort to map TSSs and identify sRNAs involved in different stress environments. In order to map the TSSs in Mtb, cDNA libraries that specifically enriched with primary transcripts were constructed for RNA sequencing, and TSSpredator was integrated for the analysis of TSSs in Mtb monitored in different stress environments. Here, a total of 8,173 TSSs were mapped in six conditions. The majority of TSSs (3,904) were detected within annotated genes (internal TSS), and 1,932 primary TSSs reside within 300 nt upstream of translation start site. 2,861 TSSs correspond to potential antisense sRNAs (antisense TSS). Finally, 215 novel TSSs are located within intergenic regions and represent potentially novel trans-encoded sRNAs.

    Item Type: Thesis (PhD)
    Subjects: R Medicine > RK Dentistry > RK1-715 Dentistry
    Divisions: Institut Perubatan & Pergigian Termaju (Advanced Medical & Dental Institute) > Thesis
    Depositing User: Mr Noorazilan Noordin
    Date Deposited: 23 Feb 2017 10:10
    Last Modified: 24 May 2017 09:15
    URI: http://eprints.usm.my/id/eprint/32190

    Actions (login required)

    View Item
    Share