TY - JOUR
T1 - The adenovirus E1A proteins induce apoptosis, which is inhibited by the E1B 19-kDa and Bcl-2 proteins
AU - Rao, L.
AU - Debbas, M.
AU - Sabbatini, P.
AU - Hockenbery, D.
AU - Korsmeyer, S.
AU - White, E.
PY - 1992
Y1 - 1992
N2 - Cooperation between the adenovirus E1A and E1B oncogenes is required for transformation of primary quiescent rodent cells. Although expression of E1A alone will stimulate cell proliferation sufficient to initiate transformed focus formation, proliferation fails to be sustained and foci degenerate. Coexpression of either the 19-kDa or 55-kDa E1B oncoproteins with E1A permits high-frequency transformation by overcoming this cytotoxic response. Without E1B 19-kDa protein expression, however, transformants remain susceptible to induction of cell death. Rapid loss of viability is coincident with nucleolytic cleavage of DNA in intranucleosomal regions and chromatin condensation, hallmarks of programed cell death (apoptosis). Furthermore, overexpression of a known suppressor of apoptosis, the Bcl-2 protooncogene, can rescue E1A-induced focus degeneration. Thus E1A-dependent stimulation of cell proliferation is accompanied by apoptosis and thereby insufficient to singly induce transformation. High-frequency transformation requires a second function encoded by the E1B 19-kDa protein to block apoptosis.
AB - Cooperation between the adenovirus E1A and E1B oncogenes is required for transformation of primary quiescent rodent cells. Although expression of E1A alone will stimulate cell proliferation sufficient to initiate transformed focus formation, proliferation fails to be sustained and foci degenerate. Coexpression of either the 19-kDa or 55-kDa E1B oncoproteins with E1A permits high-frequency transformation by overcoming this cytotoxic response. Without E1B 19-kDa protein expression, however, transformants remain susceptible to induction of cell death. Rapid loss of viability is coincident with nucleolytic cleavage of DNA in intranucleosomal regions and chromatin condensation, hallmarks of programed cell death (apoptosis). Furthermore, overexpression of a known suppressor of apoptosis, the Bcl-2 protooncogene, can rescue E1A-induced focus degeneration. Thus E1A-dependent stimulation of cell proliferation is accompanied by apoptosis and thereby insufficient to singly induce transformation. High-frequency transformation requires a second function encoded by the E1B 19-kDa protein to block apoptosis.
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U2 - 10.1073/pnas.89.16.7742
DO - 10.1073/pnas.89.16.7742
M3 - Article
C2 - 1457005
AN - SCOPUS:0026639932
VL - 89
SP - 7742
EP - 7746
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 16
ER -