RT Journal Article
T1 Involvement of loops 2 and 3 of alpha-sarcin on its ribotoxic activity
A1 Castaño Rodríguez, Carlos
A1 Olombrada Sacristán, Miriam
A1 Partida Hanon, Angélica
A1 Lacadena García-Gallo, Francisco Javier
A1 Oñaderra Sánchez, Mercedes
A1 Gavilanes, José G.
A1 García Ortega, Lucía
A1 Martínez Del Pozo, Álvaro
AB Ribotoxins are a family of fungal ribosome-inactivating proteins displaying highly specific ribonucleolytic activity against the sarcin/ricin loop (SRL) of the larger rRNA, with a-sarcin as its best-characterized member. Their toxicity arises from the combination of this activity with their ability to cross cell membranes. The involvement of a-sarcin's loops 2 and 3 in SRL and ribosomal proteins recognition, as well as in the ribotoxin-lipid interactions involving cell penetration, has been suggested some time ago.In the work presented now different mutants have been prepared in order to study the role of these loops in their ribonucleolytic and lipid-interacting properties. The results obtained confirm that loop 3 residues Lys 111, 112, and 114 are key actors of the specific recognition of the SRL. In addition, it is also shown that Lys 114 and Tyr 48 conform a network of interactions which is essential for the catalysis. Lipid-interaction studies show that this Lys-rich region is indeed involved in the phospholipids recognition needed to cross cell membranes. Loop 2 is shown to be responsible for the conformational change which exposes the region establishing hydrophobic interactions with the membrane inner leaflets and eases penetration of ribotoxins target cells.
PB Elsevier
SN 0041-0101
YR 2015
FD 2015
LK https://hdl.handle.net/20.500.14352/33752
UL https://hdl.handle.net/20.500.14352/33752
LA eng
NO Ministerio de Economía y Competitividad de España
NO Campus de Excelencia Internacional Moncloa - PICATA
DS Docta Complutense
RD 27 dic 2025