The Proteome and Transcriptome of Stress Granules and P-Bodies during Human T Lymphocytes Activation

Stress granules (SGs) and processing bodies (PBs) are membraneless cytoplasmic assemblies regulating mRNAs under environmental stress such as viral infections, neurological disorders, or cancer. Upon antigen stimulation, T lymphocytes mediate their immune functions under regulatory mechanisms involving SGs and PBs. However, the impact of T cell activation on such complexes, in term of formation, constitution and relationship remains unknown. Here, by combining proteomic, transcriptomic and immunofluorescence approaches, we simultaneously characterized the SGs and PBs from primary human T lymphocytes pre- and post-stimulation. The proteomes and transcriptomes of SGs and PBs were identified, unveiling an unanticipated molecular and functional complementarity. Notwithstanding, these granules keep distinct spatial organizations and abilities to interact with mRNAs. This comprehensive characterization of the RNP granule proteomic and transcriptomic landscapes provides a unique resource for future investigations on SGs and PBs in T lymphocytes. To identified the RNAs in SGs and PBs of primary human T lymphocytes, we first isolated CD3+ T lymphocytes from PBMCs of 5 human healthy donors. SGs and PBs were isolated from T Lymphocytes following 72 h stimulation with CD3/CD28 activating beads. In addition, total cytosolic (CYT) RNAs were extracted.