INVESTIGADORES
CERUTI Julieta Maria
congresos y reuniones científicas
Título:
MUTATION OF ING1 TUMOR SUPRESSOR DETECTED IN HUMAN NEOPLASIA ABROGATES DNA REPAIR.
Autor/es:
CERUTI, JULIETA; MARTÍN-GARRIDO, E; PALMERO, IGNACIO; CÁNEPA, EDUARDO
Lugar:
Iguazú, Argentina
Reunión:
Congreso; XL Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2004
Institución organizadora:
SAIB
Resumen:
CB-P39.
MUTATION OF ING1 TUMOR SUPPRESSOR DETECTED
IN HUMAN NEOPLASIA ABROGATES DNA REPAIRING1 TUMOR SUPPRESSOR DETECTED
IN HUMAN NEOPLASIA ABROGATES DNA REPAIR
Ceruti J1, Martín-Garrido E2, Palmero I2, Cánepa E1.1, Martín-Garrido E2, Palmero I2, Cánepa E1.
1Depto Química Biológica, FCEyN-UBA, Buenos Aires, Argentina
and 2Instituto de Investigaciones Biomédicas, UAM, Madrid,
España. E-mail: ecanepa@qb.fcen.uba.arDepto Química Biológica, FCEyN-UBA, Buenos Aires, Argentina
and 2Instituto de Investigaciones Biomédicas, UAM, Madrid,
España. E-mail: ecanepa@qb.fcen.uba.ar2Instituto de Investigaciones Biomédicas, UAM, Madrid,
España. E-mail: ecanepa@qb.fcen.uba.ar
The tumor suppressor ING1 inhibits cell growth in G1 phase by
transactivating the CDK inhibitor p21waf1. Its biological functions
have been studied in the last years and have been reported to
mediate senescence, apoptosis and DNA repair. In this study, we
investigated the involvement of p33ING1 (one of ING1 isoforms)
in the modulation of DNA repair and the effect of point mutations
on this p33 activity. We first examined whether p33ING1 responds
to UVC in HeLa cell line. By northern blot, we found that UV
light induces expression of p33 in a dose- and time-dependent
manner. Western blots reveal a concomitant protein induction. To
determine if p33 mediates DNA repair in HeLa cells, we used the
host-cell-reactivation assay (HCR) where a UV-damaged plasmid
is contransfected with p33 expression vector. Our data show that
cells overexpressing p33 increase the rate of repair of the UVdamaged
plasmid. To investigate whether ING1 mutation affects
DNA repair, we assessed HCR assays using expression vectors
codifying point mutations C215S or K270N. While C215S did not
affect p33 ability to improve DNA repair, K270N reduced CAT
activity. Similar results were obtained by means of unscheduled
DNA synthesis assay, that evaluates the extent of repair of genomic
DNA in UV irradiated cells. These results demonstrate that
p33ING1 mutation, detected in human neoplasia, reduces the NER
capacity, leading to an increased genomic instability, a condition
that favors tumor progressionING1 mutation affects
DNA repair, we assessed HCR assays using expression vectors
codifying point mutations C215S or K270N. While C215S did not
affect p33 ability to improve DNA repair, K270N reduced CAT
activity. Similar results were obtained by means of unscheduled
DNA synthesis assay, that evaluates the extent of repair of genomic
DNA in UV irradiated cells. These results demonstrate that
p33ING1 mutation, detected in human neoplasia, reduces the NER
capacity, leading to an increased genomic instability, a condition
that favors tumor progression