Phytophthora capsici infection causes dynamic alterations in tRNA modifications and their associated gene candidates in black pepper

The efforts to signify the relevance of tRNA modifications were always within the limits of prokaryotes, humans, and some fewer model plant systems. The story of tRNA modifications in higher plants is still overlooked, especially in non-model spice crops. Stress causes alterations in tRNA modifications to facilitate the downstream functions of tRNAs. The present study was done to identify and better understand the fate of tRNA nucleoside modifications during biotic stress response in a widely used spice crop called Black pepper. We have uncovered the various tRNA nucleoside modifications present in black pepper. Methylations were the predominant nucleoside modifications in black pepper tRNAs. Furthermore, the different methyltransferase gene candidates implicated in catalyzing tRNA nucleoside methylations in black pepper were also identified. The LC-MS profile showed that certain tRNA nucleoside modifications showed varied abundance upon P. capsici infection. The N4-acetylcytidine (ac4C) nucleoside modification has shown a constant hike at 24 and 48 hpi. At the same time, some nucleoside modifications have exhibited a time-dependent abundance. Altogether our study suggests that tRNA modifications and the expression of associated enzymes are altered during biotic stress regulation.