RLD proteins, or Ribosome-Like Domain proteins, are a group of proteins that play a crucial role in cellular functions, particularly in the synthesis of proteins. They are characterized by their structural similarity to ribosomes, which are the cellular machinery responsible for translating messenger RNA into proteins. RLD proteins are involved in various biological processes, including cell growth and response to stress. These proteins are found in many organisms, from bacteria to humans, and their functions can vary widely. Some RLD proteins are essential for maintaining cellular integrity, while others are involved in regulating gene expression. Understanding RLD proteins can provide insights into fundamental biological processes and potential therapeutic targets for diseases.