Sense overlapping transcripts in IS1341-type transposase genes are functional non-coding RNAs in archaea

Area of Science:

• Molecular Biology
• Genomics
• Microbial Genetics

Background:

• Prokaryotic gene expression exhibits complexity through sense overlapping transcripts (sotRNAs) sharing regulatory and coding information.
• Transposable elements, like IS1341, contribute to genomic dynamics and gene regulation.

Purpose of the Study:

• To discover and characterize ncRNAs associated with IS1341-type transposase (tnpB) genes.
• To investigate the regulatory roles and functional significance of these sotRNAs in Halobacterium salinarum.
• To identify conserved sequence motifs within these ncRNAs.

Main Methods:

• Bioinformatic analysis of publicly available transcriptome data.
• Identification and characterization of sotRNAs in Halobacterium salinarum NRC-1.
• Experimental overexpression of identified ncRNAs in H. salinarum.

Main Results:

• Discovery of sotRNAs associated with all IS1341-type transposases in H. salinarum.
• Demonstration of condition-dependent differential regulation between sotRNAs and their cognate genes.
• Identification of a conserved UUCA tetraloop motif in archaeal ncRNAs (HgcC family) and a PATE-derived ncRNA.
• Overexpression of a sotRNA and a PATE-derived RNA containing the motif enhanced H. salinarum growth.

Conclusions:

• Sense overlapping transcripts represent a significant layer of gene expression regulation in prokaryotes.
• The identified UUCA tetraloop motif suggests a conserved functional role for these ncRNAs across archaea.
• These ncRNAs are functionally active, influencing microbial growth and potentially other cellular processes.