Papillomavirus-associated inductions of cellular proteins in mouse C127 cells: correlation with the presence of open reading frame E2.
Bovine papillomavirus type 1 (BPV-1) readily transforms mouse C127 cells, conferring the ability to grow in soft agar and to form tumors in athymic (nu/nu) mice. Electrophoresis of total cellular proteins from these BPV-transformed lines on ultra-high resolution, giant two-dimensional gels displays the presence of novel, papillomavirus-related protein phenotypes. Analysis of the established BPV-1-transformed C127 cell lines, ID13 and ID14, reveals a set of six proteins which are either absent or synthesized at extremely low levels in the parental cell line. One of these proteins is also present in v-ras-transformed C127 cells, but none of the others are found in cells transformed by a variety of viral oncogenes, including the polyomavirus middle T, v-mos, or v-fes. The genome of BPV-1 contains two separate open reading frames (ORFs), E5 and E6, which can act independently to transform C127 cells. In addition, trans-activator and repressor proteins encoded respectively by the full-length and carboxy-terminal E2 ORF regulate the level of expression of other BPV-1 genes. We examined 34 cell lines transformed by intact and subgenomic recombinant DNAs of BPV-1. Cells harboring BPV-1 DNAs engineered to eliminate the expression of ORFs E4, E5, E6, or E7 display five of the PV-associated proteins, but these proteins are not seen in lines lacking the full E2 ORF. Moreover, G418-selected nontransformed cells expressing E2 cDNA from an SV40 promoter exhibit these proteins at high levels. Surprisingly, these proteins are also present in cells containing BPV-1 DNAs with amino-terminal E2 deletions, suggesting that these PV-associated proteins represent novel cellular responses to a factor encoded within the E2-C gene region.
Levenson
R M
RM
Department of Medicine, University of Rochester School of Medicine and Dentistry, New York 14642.
Brinckmann
U G
UG
O'Banion
M K
MK
Androphy
E J
EJ
Schiller
J T
JT
Tabatabai
F
F
Turek
L P
LP
Neary
K
K
Chin
M T
MT
Broker
T R
TR
D000818:Animals; D052688:Bovine papillomavirus 1 / Q000235:genetics*; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional; D005786:Gene Expression Regulation; D005814:Genes, Viral; D051379:Mice; D027383:Papillomaviridae / Q000235:genetics*; D011506:Proteins / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014764:Viral Proteins / Q000235:genetics*
D004268:DNA-Binding Proteins; C051550:E2 protein, Bovine papillomavirus; D011506:Proteins; D014764:Viral Proteins