Regulatory proteins are a class of proteins that play a crucial role in controlling gene expression and cellular processes in living organisms. These proteins can interact with DNA, RNA, or other proteins to either activate or repress the expression of specific genes. By regulating gene expression, regulatory proteins help maintain the proper functioning of cells and organisms. They are involved in a wide range of biological processes, such as development, cell growth and differentiation, metabolism, and response to environmental stimuli. Dysfunction or mutations in regulatory proteins can lead to diseases and disorders, highlighting their importance in maintaining overall health and homeostasis in organisms.