S1_RPS1_repeat_ec4: Ribosomal protein S1 (RPS1) domain. RPS1 is a component of the small ribosomal subunit thought to be involved in the recognition and binding of mRNA's during translation initiation. The bacterial RPS1 domain architecture consists of 4-6 tandem S1 domains. In some bacteria, the tandem S1 array is located C-terminal to a 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HMBPP reductase) domain. While RPS1 is found primarily in bacteria, proteins with tandem RPS1-like domains have been identified in plants and humans, however these lack the N-terminal HMBPP reductase domain. This CD includes S1 repeat 4 (ec4) of the Escherichia coli RPS1. Autoantibodies to double-stranded DNA from patients with systemic lupus erythematosus cross-react with the human RPS1 homolog.
Jiyao W et al.(2023). "The conserved domain database in 2023.",