TY - JOUR
T1 - Redundant control of adenovirus late gene expression by early region 4
AU - Bridge, E.
AU - Ketner, G.
PY - 1989
Y1 - 1989
N2 - A series of human adenovirus type 5 derivatives carrying deletion mutations in early region 4 (E4) were constructed and characterized with respect to viral late protein synthesis, viral cytoplasmic late message accumulation, viral DNA accumulation, and plaquing ability. Viral late protein synthesis was essentially normal in cells infected by mutants expected to produce either the E4 open reading frame (ORF) 3 product or the E4 ORF 6 product. In cells infected by mutants lacking both ORF 3 and ORF 6, late protein synthesis was dramatically reduced. The basis for this reduction appears to be a concomitant reduction in cytoplasmic late message levels. Our results suggest that the products of ORFs 3 and 6 are redundant, since they are individually able to satisfy the requirements for E4 in late gene expression. Two of the mutants examined were defective for viral late protein synthesis but showed no measurable defect in viral DNA accumulation. The defect in late gene expression is not, therefore, a reflection of a primary defect in viral DNA synthesis. Finally, mutants expected to express ORF 3 or ORF 6 formed plaques with normal or only modestly reduced efficiency, whereas mutants expected to express neither ORF formed plaques with an efficiency less than 10-6 that of wild-type virus. Thus, plaque-forming ability reflected late protein synthetic ability, suggesting that among these mutants late protein synthetic proficiency is the principle determinant of plaquing efficiency.
AB - A series of human adenovirus type 5 derivatives carrying deletion mutations in early region 4 (E4) were constructed and characterized with respect to viral late protein synthesis, viral cytoplasmic late message accumulation, viral DNA accumulation, and plaquing ability. Viral late protein synthesis was essentially normal in cells infected by mutants expected to produce either the E4 open reading frame (ORF) 3 product or the E4 ORF 6 product. In cells infected by mutants lacking both ORF 3 and ORF 6, late protein synthesis was dramatically reduced. The basis for this reduction appears to be a concomitant reduction in cytoplasmic late message levels. Our results suggest that the products of ORFs 3 and 6 are redundant, since they are individually able to satisfy the requirements for E4 in late gene expression. Two of the mutants examined were defective for viral late protein synthesis but showed no measurable defect in viral DNA accumulation. The defect in late gene expression is not, therefore, a reflection of a primary defect in viral DNA synthesis. Finally, mutants expected to express ORF 3 or ORF 6 formed plaques with normal or only modestly reduced efficiency, whereas mutants expected to express neither ORF formed plaques with an efficiency less than 10-6 that of wild-type virus. Thus, plaque-forming ability reflected late protein synthetic ability, suggesting that among these mutants late protein synthetic proficiency is the principle determinant of plaquing efficiency.
UR - http://www.scopus.com/inward/record.url?scp=0024571586&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024571586&partnerID=8YFLogxK
U2 - 10.1128/jvi.63.2.631-638.1989
DO - 10.1128/jvi.63.2.631-638.1989
M3 - Article
C2 - 2911117
AN - SCOPUS:0024571586
SN - 0022-538X
VL - 63
SP - 631
EP - 638
JO - Journal of virology
JF - Journal of virology
IS - 2
ER -