Jovana Dinic / Predoc
mRNA-binding proteins in β-cell function
The rapid increase in proinsulin biosynthesis in β-cells after glucose stimulation is the result of post-transcriptional up-regulation. Glucose also post-transcriptionally enhances the expression of other components of insulin secretory granules (SGs). Prompt biogenesis of new insulin SGs is critical to replenish depleted insulin stores, especially because newly synthesized SGs are preferentially released. The post-transcriptional mechanisms that regulate SG biogenesis are largely unknown. A number of mRNA-binding proteins, such as PTBP1 and HuD have been shown to bind to insulin and SG protein mRNAs and influence their stability and translation. These proteins can be part of large ribonucleoprotein (RNP) complexes for control of gene expression at a post-transcriptional level. The significance of mRNA-binding proteins in insulin and SG biogenesis is widely acknowledged, however, glucose-induced changes in RNPs of β-cells have not yet been thoroughly analyzed. The aim of my project is to examine the composition of mRNP complexes before and after glucose stimulation of β-cells. Elucidating the composition and activity of these RNPs is key for a better understanding of the post-transcriptional mechanisms involved in insulin and SG biogenesis.