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bioRxiv · 10.1101/2021.10.20.465156

Nutritional dependence of sperm mitochondrial metabolism and small RNA biogenesis

Ramesh, R.·Skog, S.·Nätt, D.·Kugelberg, U.·Örkenby, L.·Öst, A.
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Abstract

A wide spectrum of exogenous factors, including diet, environmental pollutants, stress, and seasonal changes have major impact on sperm quality and function. The molecular basis, however, that explains this susceptibility remains largely unknown. Using a combination of proteomics and small RNA (sRNA) sequencing, we show that Drosophila sperm display rapid molecular changes in response to dietary sugar, both in terms of metabolic/redox proteins and sRNA content, particularly miRNA and mitochondria derived sRNA (mt-sRNA). Thus, results from two independent omics point at the dynamics of mitochondria as the central aspect in rapid metabolic adjustments in sperm. Using specific stains and in vivo redox reporter flies, we show that diet indeed rapidly alters the production of mitochondrial derived reactive oxygen species (ROS). Quenching ROS via supplementation of N acetyl cysteine reduces diet-upregulated miRNA, but not mitochondrial-sRNA. Together, these results open new territories in our search for the mechanistic understanding of sperm health and disease. HighlightsO_LIDiet rapidly changes the proteomic and sRNA profiles in sperm C_LIO_LIDiet sensitive sperm proteins are found in human infertility studies C_LIO_LISperm mitochondrial ROS levels are modulated by diet C_LIO_LIdme-miR-10 regulation is secondary to diet-induced ROS C_LIO_LIDiet, but not diet-induced ROS, alters the expression of mitochondrial small RNA, especially tsRNA C_LI

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Ramesh, R., Skog, S., Nätt, D., Kugelberg, U., Örkenby, L., Öst, A.. 2021-10-20. Nutritional dependence of sperm mitochondrial metabolism and small RNA biogenesis. https://doi.org/10.1101/2021.10.20.465156

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