The Effect of the Knockout of Major Transsulfuration Genes on the Pattern of Protein Synthesis in D. melanogaster

The enzymes involved in the transsulfuration pathway and hydrogen sulfide production – cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST) – play an important cytoprotective role in the functioning of the organism. Using CRISPER/Cas9 technology, we obtained Drosophila lines with deleted cbs, cse, and mst genes as well as with double deletion of cbs and cse genes. We analyzed the effect of these mutations on the pattern of protein synthesis in the salivary glands of third instar larvae and in the ovaries of mature flies. In the salivary glands of lines with cbs and cse deletions, a decrease was found in the accumulation of the FBP2 storage protein containing 20% methionine amino acid residues. In the ovaries, changes were detected in the level of expression and isofocusing points of proteins involved in cell protection against oxidative stress, hypoxia, and protein degradation. It was shown that in the lines with deletions of transsulfuration enzymes the proteins have a similar degree of oxidation to that of the control line. A decrease in the total number of proteasomes and their activity was found in the lines with deletions of the cbs and cse genes.