ANG and viral infectious disease: Recently, a new type of tRNA has emerged, called tRNA-derived small RNAs or tDRs, which are produced after cleavage at specific sites in the codon or anti-codon loop by restrictive enzymes such as angiogenin (ANG), responsible for cleaving the anticodon loop of mature tRNAs under stressful conditions (such as hypoxia, lack of amino acids, oxidative stress, ultraviolet radiation, heat shock, and viral infection) [51,52].