Ribosomal protein L11. Ribosomal protein L11, together with proteins L10 and L7/L12, and 23S rRNA, form the L7/L12 stalk on the surface of the large subunit of the ribosome. The homologous eukaryotic cytoplasmic protein is also called 60S ribosomal protein L12, which is distinct from the L12 involved in the formation of the L7/L12 stalk. The C-terminal domain (CTD) of L11 is essential for binding 23S rRNA, while the N-terminal domain (NTD) contains the binding site for the antibiotics thiostrepton and micrococcin. L11 and 23S rRNA form an essential part of the GTPase-associated region (GAR). Based on differences in the relative positions of the L11 NTD and CTD during the translational cycle, L11 is proposed to play a significant role in the binding of initiation factors, elongation factors, and release factors to the ribosome. Several factors, including the class I release factors RF1 and RF2, are known to interact directly with L11. In eukaryotes, L11 has been implicated in regulating the levels of ubiquinated p53 and MDM2 in the MDM2-p53 feedback loop, which is responsible for apoptosis in response to DNA damage. In bacteria, the "stringent response" to harsh conditions allows bacteria to survive, and ribosomes that lack L11 are deficient in stringent factor stimulation.