RACK1 and viral infectious disease: Emerging evidence suggests that ribosome heterogeneity resulting from the alteration of ribosomal components regulates the selective translation of specific mRNAs.54 Similarly, ribosomal RACK1 contributes to the selective translation of specific mRNAs,55 and is involved in IRES-dependent translation after viral infection stress.17 Here, as global translation and polysomal fraction were slightly decreased in RACK1 siRNA-transfected cells (Supplementary Figures S4C and D), depletion of ribosomal RACK1 affects the translation of specific mRNAs, such as LC3 and Bcl-xL (Figure 5b).