We are interested in interactions involving hnRNP proteins participating in several steps of mRNA processing (mainly pre-mRNA splicing) and HuR with an established role in stability/translation of associated mRNAs. hnRNP and HuR proteins have a major nucleoplasmic localization and ability to shuttle between nucleus and cytoplasm. We report here on interactions between hnRNP and HuR proteins that were identified in the context of isolated hnRNP and mRNP complexes.