Protein Domain : Pseudouridine synthase, RluA-like, conserved site IPR006224

Type	Conserved_site
Description	Pseudouridine synthases catalyse the isomerisation of uridine to pseudouridine (Psi) in a variety of RNA molecules, and may function as RNA chaperones. Pseudouridine is the most abundant modified nucleotide found in all cellular RNAs. There are four distinct families of pseudouridine synthases that share no global sequence similarity, but which do share the same fold of their catalytic domain(s) and uracil-binding site and are descended from a common molecular ancestor. The catalytic domain consists of two subdomains, each of which has an α+β structure that has some similarity to the ferredoxin-like fold (note: some pseudouridine synthases contain additional domains). The active site is the most conserved structural region of the superfamily and is located between the two homologous domains. These families are [ , ]:Pseudouridine synthase I, TruA.Pseudouridine synthase II, TruB, which contains and additional C-terminal PUA domain.Pseudouridine synthase RsuA. RluB, RluE and RluF are also part of this family.Pseudouridine synthase RluA. TruC, RluC and RluD belong to this family.Pseudouridine synthase TruD, which has a natural circular permutation in the catalytic domain, as well as an insertion of a family-specific α+β subdomain.This entry represents a conserved region located in the central part of a group of pseudouridine synthases, predominantly those that belong to the RluA subfamily of pseudouridine synthases, including RluA, RluC, RluD and TruC. These homologous enzymes synthesize pseudouridine from uracil in specific positions [ , , ]. RluD also possesses a second function related to proper assembly of the 50S ribosomal subunit that is independent of Psi-synthesis []. RluA shows an elongated, mixed α/β fold, with an with an eight-stranded β-sheet core and additional β-strands, α-helices and loops []. Despite the conserved topology shared by RluC and RluD, the surface shape and charge distribution are very different [].
Short Name	PsdUridine_synth_RluA-like_CS