In all living organisms, the ability to properly modulate gene expression patterns is vital for survival and when cells are unable to quickly respond to cellular changes, the result can be detrimental. Rny1 is a ribonuclease which helps enable rapid adaptation of gene expression through the degradation of RNA. Despite its importance, Rny1, which is found in S. cerevisiae, and its human ortholog, RNASET2, are still poorly understood. Using RT-qPCR, which quantifies mRNA levels, we measured RNY1 mRNA levels during two different yeast growth phases. Our findings suggests that RNY1 is not expressed during fermentation but becomes prevalent when the mitochondria switch to respiration due to a lack of glucose in their environment. These findings, in conjunction with previous research showing that cells that lack Rny1 function leads to increased levels of mitochondrial mRNAs, lead us to believe that Rny1 acts as a rheostat to temper gene expression to promote proper mitochondria respiration or reduce oxidative stress. We then looked at specific mRNA targets that may be degraded by Rny1 using the TET-off system. We were able to reduce the transcription of an mRNA encoding an important protein for respiration. With further investigation of Rny1, we will better understand important mRNA decay patterns required for respiration and a target for prevent harmful mitochondrial dysfunction.