Final answer:
Glycosylation and phosphorylation are types of post-translational modifications that alter proteins' structure and function. Phosphorylation, catalyzed by kinases, can regulate enzyme activity and signal transduction pathways, impacting gene expression.
Step-by-step explanation:
Glycosylation and phosphorylation are two prominent examples of post-translational modifications. These modifications enhance the molecular and functional diversity of proteins. Phosphorylation is a critical modification where a phosphate group is added to molecules like proteins, often on serine, threonine, and tyrosine residues. This process, catalyzed by enzymes called kinases, can activate or inactivate the enzymes, affect their activity, and create binding sites for further interactions in signaling pathways. Conversely, dephosphorylation by phosphatases can reverse the effects of phosphorylation. Protein modifications such as these can alter gene expression by influencing protein stability, localization, and activity, ultimately affecting cellular functions and processes.