mRNA processing by RNases J1 and J2 affects Bacillus subtilis gene expression on a global scale

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Bacillus subtilis possesses two paralogous enzymes, Ribonucleases J1 and J2, with dual endo- and exoribonucleolytic activities.
• These enzymes share similarities in cleavage specificity with E. coli's RNase E, a key RNA processing factor.
• The specific biological roles of RNases J1 and J2 in Bacillus subtilis remain largely unelucidated.

Purpose of the Study:

• To investigate the biological significance of Bacillus subtilis ribonucleases J1 and J2.
• To determine the impact of these enzymes on gene expression and RNA stability.
• To understand the functional overlap and distinct roles of RNases J1 and J2.

Main Methods:

• Comparative transcriptomic and proteomic analyses of wild-type, single, and double mutant Bacillus subtilis strains lacking RNases J1 and J2.
• Measurement of individual mRNA half-lives to assess transcript stability.
• Analysis of gene expression levels under different enzymatic conditions.

Main Results:

• The simultaneous absence or significant reduction of both RNases J1 and J2 profoundly alters the expression levels of hundreds of genes.
• Single mutant strains exhibit minimal changes in global gene expression, indicating largely overlapping substrate specificities between RNases J1 and J2.
• RNases J1 and J2 modulate gene expression by influencing transcript stability, with their absence leading to both increases and decreases in transcript abundance.

Conclusions:

• Ribonucleases J1 and J2 play a complex, significant role in regulating gene expression in Bacillus subtilis.
• These enzymes are involved in both RNA degradation and regulatory processing events.
• The overlapping functions of RNases J1 and J2 are critical for maintaining cellular homeostasis and gene expression patterns.