Complete identity and expression of StfZ, the cis-antisense RNA to the mRNA of the cell division gene ftsZ, in Escherichia coli

Deepak Anand; Kishor Jakkala; Rashmi Ravindran Nair; Deepti Sharan; Atul Pradhan; Nagaraja Mukkayyan; Parthasarathi Ajitkumar

doi:10.3389/fmicb.2022.920117

Complete identity and expression of StfZ, the cis-antisense RNA to the mRNA of the cell division gene ftsZ, in Escherichia coli

Front Microbiol. 2022 Oct 19:13:920117. doi: 10.3389/fmicb.2022.920117. eCollection 2022.

Authors

Deepak Anand^{1

2}, Kishor Jakkala^{1

3}, Rashmi Ravindran Nair^{1

4}, Deepti Sharan^{1

5}, Atul Pradhan^{1

6}, Nagaraja Mukkayyan^{1

7}, Parthasarathi Ajitkumar¹

Affiliations

¹ Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India.
² Department of Biology, Lund University, Lund, Sweden.
³ Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, United States.
⁴ Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States.
⁵ Department of Microbiology, The University of Chicago, Chicago, IL, United States.
⁶ Department of Medicine, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, United States.
⁷ Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States.

Abstract

Bacteria regulate FtsZ protein levels through transcriptional and translational mechanisms for proper cell division. A cis-antisense RNA, StfZ, produced from the ftsA-ftsZ intergenic region, was proposed to regulate FtsZ level in Escherichia coli. However, its structural identity remained unknown. In this study, we determined the complete sequence of StfZ and identified the isoforms and its promoters. We find that under native physiological conditions, StfZ is expressed at a 1:6 ratio of StfZ:ftsZ mRNA at all growth phases from three promoters as three isoforms of 366, 474, and 552 nt RNAs. Overexpression of StfZ reduces FtsZ protein level, increases cell length, and blocks cell division without affecting the ftsZ mRNA stability. We did not find differential expression of StfZ under the stress conditions of heat shock, cold shock, or oxidative stress, or at any growth phase. These data indicated that the cis-encoded StfZ antisense RNA to ftsZ mRNA may be involved in the fine tuning of ftsZ mRNA levels available for translation as per the growth-phase-specific requirement at all phases of growth and cell division.

Keywords: Escherichia coli; FtsZ level; StfZ cis-antisense RNA; cell division; ftsZ mRNA.