10.1111/j.1742-4658.2010.07709.x
The research investigates the substrate specificity and kinetic properties of the scavenger decapping enzyme (DcpS) from Caenorhabditis elegans. The study aims to understand how DcpS recognizes and hydrolyzes various mRNA cap structures, which is crucial for mRNA turnover and gene expression regulation. Key findings include the enzyme's ability to hydrolyze both monomethylated (m7GpppG) and trimethylated (m3 2,2,7GpppG) caps, with the latter being cleaved at a higher rate but with lower specificity. The study also revealed that modifications in the first transcribed nucleotide did not significantly affect DcpS activity, indicating flexibility in the first transcribed nucleoside-binding pocket. However, 2'-O- and 3'-O-methylations of 7-methylguanosine significantly reduced hydrolysis rates. These results provide insights into the structural requirements for DcpS substrates and highlight the enzyme's role in mRNA degradation pathways, potentially aiding in the design of selective inhibitors for parasitic nematode DcpSs. The research underscores the significance of 7-methylguanosine in the cap structure and its influence on the enzymatic activity of DcpS, providing valuable insights into the molecular mechanisms of mRNA decapping and degradation.
