Translational regulation of mRNA is an immediate and precise mechanism to control gene expression in various biological processes, including development, differentiation, and responses to extracellular stress. Global quantification analysis indicates that the cellular abundance of proteins in mammals is predominantly controlled at the level of translation (1). In vivo, mRNAs do not exist as bare mRNA molecules but as mRNA-protein complexes with RNA-binding proteins (RBPs). More than one thousand RBPs have been identified, and they bind to specific cis-acting elements, consisting of sequence elements, stem-loop structures and/or modified nucleotides. For many genes, alternative poly (A) addition and alternative splicing give rise to 3’-UTR variants. These variants are controlled by specific post-transcriptional regulation. The cap-dependent mRNA translational process is divided into three major steps: initiation, elongation, and termination. Each step is elaborately regulated by multiple mRNA 3’-UTR binding proteins in a cell type- and species-specific manner. We are challenging this new frontier of the RNA based biology by combining biochemistry, molecular biology, and cellular biology and mice.