The ftsZ Gene of Mycobacterium smegmatis is expressed Through Multiple Transcripts
Sougata Roy1, 2, Deepak Anand1, Srinivasan Vijay1, Prabuddha Gupta1, 3, Parthasarathi Ajitkumar1, *
Identifiers and Pagination:Year: 2011
First Page: 43
Last Page: 53
Publisher Id: TOMICROJ-5-43
Article History:Received Date: 17/5/2011
Revision Received Date: 3/6/2011
Acceptance Date: 7/6/2011
Electronic publication date: 11/7/2011
Collection year: 2011
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
The principal essential bacterial cell division gene ftsZ is differentially expressed through multiple transcripts in diverse genera of bacteria in order to meet cell division requirements in compliance with the physiological niche of the organism under different environmental conditions. We initiated transcriptional analyses of ftsZ gene of the fast growing saprophytic mycobacterium, Mycobacterium smegmatis, as the first step towards understanding the requirements for FtsZ for cell division under different growth phases and stress conditions. Primer extension analyses identified four transcripts, T1, T2, T3, and T4. Transcriptional fusion studies using gfp showed that the respective putative promoter regions, P1, P2, P3, and P4, possessed promoter activity. T1, T2, and T3 were found to originate from the intergenic region between ftsZ and the upstream gene, ftsQ. T4 was initiated from the 3’ portion of the open reading frame of ftsQ. RT-PCR analyses indicated co-transcription of ftsQ and ftsZ. The four transcripts were present in the cells at all growth phases and at different levels in the cells exposed to a variety of stress conditions in vitro. T2 and T3 were absent under hypoxia and nutrient-depleted stationary phase conditions, while the levels of T1 and T4 remained unaffected. These studies showed that ftsZ gene expression through multiple transcripts and differential expression of the transcripts at different growth phases and under stress conditions are conserved in M. smegmatis, like in other Actinomycetes.