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Structures and Ribosomal Interaction of Ribosome-Inactivating Proteins.

ABSTRACT: Ribosome-inactivating proteins (RIPs) including ricin, Shiga toxin, and trichosanthin, are RNA N-glycosidases that depurinate a specific adenine residue (A-4324 in rat 28S ribosomal RNA, rRNA) in the conserved ?-sarcin/ricin loop (?-SRL) of rRNA. RIPs are grouped into three types according to the number of subunits and the organization of the precursor sequences. RIPs are two-domain proteins, with the active site located in the cleft between the N- and C-terminal domains. It has been found that the basic surface residues of the RIPs promote rapid and specific targeting to the ribosome and a number of RIPs have been shown to interact with the C-terminal regions of the P proteins of the ribosome. At present, the structural basis for the interaction of trichosanthin and ricin-A chain toward P2 peptide is known. This review surveys the structural features of the representative RIPs and discusses how they approach and interact with the ribosome.

SUBMITTER: Shi WW

PROVIDER: S-EPMC6273143 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Structures and Ribosomal Interaction of Ribosome-Inactivating Proteins.

Shi Wei-Wei WW Mak Amanda Nga-Sze AN Wong Kam-Bo KB Shaw Pang-Chui PC

Molecules (Basel, Switzerland) 20161121 11

Ribosome-inactivating proteins (RIPs) including ricin, Shiga toxin, and trichosanthin, are RNA <i>N</i>-glycosidases that depurinate a specific adenine residue (A-4324 in rat 28S ribosomal RNA, rRNA) in the conserved α-sarcin/ricin loop (α-SRL) of rRNA. RIPs are grouped into three types according to the number of subunits and the organization of the precursor sequences. RIPs are two-domain proteins, with the active site located in the cleft between the N- and C-terminal domains. It has been foun ...[more]

PMID: 27879643

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