Transcriptome sequencing and screening of genes related to glucose availability in Schizosaccharomyces pombe by RNA-seq analysis

Abstract

While calorie restriction is the most used experimental intervention to increase lifespan in numerous model organisms, increasing evidence suggests that excess glucose leads to decreased lifespan in various organisms. To fully understand the molecular basis of the pro-aging effect of glucose, it is still important to discover genetic interactions, gene expression patterns, and molecular responses depending on glucose availability. Here, we compared the gene expression profiles in Schizosaccharomyces pombe mid-log-phase cells grown in three different Synthetic Dextrose media with 3%, 5%, and 8% glucose, using the RNA sequencing method. Expression patterns of genes that function in carbohydrate metabolism were downregulated as expected, and these genes were downregulated in line with the increase in glucose content. Significant and consistent changes in the expression were observed such as genes that encoding retrotransposable elements, heat shock proteins, glutathione S-transferase, cell agglutination protein, and conserved fungal proteins. We group some genes that function together in the transcription process and mitotic regulation, which have recently been associated with glucose availability. Our results shed light on the relationship between excess glucose, diverse cellular processes, and aging.

Figure 1 -. Classification of raw reads in samples A) T1, B) T2, C) T3.

Figure 2 -. Differential expression levels of T1, T2, and T3 samples. Yellow and blue color represent differentially expressed genes, Brown color represents the genes whose expression does not differ in samples.

Figure 3 -. The gene numbers of differentially expressed genes. Blue color represents downregulation and yellow color represents upregulation.

Figure 4 -. GO classification of differentially expressed genes between groups, A) T1 vs T3, B) T2 vs T1, C) T2 vs T3.

Figure 5 -. Chart of top 20 pathways between different treatment groups.

Figure 6 -. The putative interaction map of proteins that encoded by all genes whose expression were significantly changed acording to glucose availability. Network was created through STRING website (ver. 11.0). Interaction sources included experiments, databases, co-expression, neighborhood, gene fusion and co-ocurrence. Minimum required interaction score was set as 0.400. Detailed explanation is given in the text.