INVESTIGADORES
CASABONA Juan Cruz
congresos y reuniones científicas
Título:
Mapping the tacative virus Z protein binding sites on the l polymerase protein.
Autor/es:
MAXIMILIANO WILDA; NORA LOPEZ; CASABONA J.C; MARIA T. FRANZE-FERNANDEZ
Reunión:
Conferencia; Negative Strand Virus Conference 2006. Salamanca, Spain.; 2006
Institución organizadora:
International Negative Strand Viruses Society
Resumen:
The arenavirus Tacaribe ( TacV ) comprises a single phylogenetic
lineage together with the four South American pathogenic producers of
severe hemorrhagic disease. TacV genome encodes four proteins : the
precursor of the viral glycoproteins, the nucleocapsid protein, the
large L protein ( 2210 aminoacids ) containing sequence motifs of
RNA-dependent RNA polymerases of negative-strand RNA viruses and a
95-aminoacid RING-finger protein called Z. Using a reverse-genetic
system we have previously demonstrated that TacV-Z protein inhibits
viral RNA synthesis by direct interaction with the L polymerase (
J.Virol. 77:10383-10393 : 2003 ). To delineate the regions involved in
the interaction with Z, C-terminal, N-terminal and site-directed
mutations in L were characterized for their ability to form a complex
with Z as detected by coimmunoprecipitation. It was found that Z-L
interactions were not disrupted by deletions of up to 550 aminoacids
within the C-terminal sequence of the L molecule whereas a further 220
aminoacids truncation comprising approximately 50 aminoacids of the
C-terminal portion of L-predicted region III, reduced the interaction
to about 7 % of WT L. Site-directed mutagenesis within region III
identified nine aminoacids important for binding Z. Complex formation
studies using L mutants with N-terminal deletions suggested a second
region of interaction within aminoacids 1-392.