Expression of Egr-1 correlates with the transformed phenotype and the type of viral latency in EBV genome positive lymphoid cell lines.
In this paper we have investigated the role of Egr-1 in B cell growth regulation by examining the gene expression in a panel of B cell lines, including both EBV genome negative and EBV carrying cell lines. Egr-1 expression correlates with the cellular phenotype and the specific pattern of viral latency established within the individual cell lines. Thus, constitutive activation of Egr-1 gene is invariably associated with unrestricted expression of viral latent genes in all group III EBV genome carrying cell lines. In contrast, Egr-1 expression is abrogated in group I Burkitt tumor cells, irrespective of the EBV genome carrying status. Activated viral gene expression associated with phenotypic conversion of group I cell lines in to group II or III restores the Egr-1 gene expression. Several forms of EGR-1 protein are found within the different groups of cell lines, and the binding activity to DNA consensus sequences was investigated. Finally, time course analysis of Egr-1 expression during the early steps of EBV infection in vitro demonstrated that Egr-1 is upregulated within minutes from the initial interaction with the B lymphocyte.
Calogero
A
A
Istituto Neurologico Mediterraneo, IRCCS Neuromed, Pozzilli, Italy.
Cuomo
L
L
D'Onofrio
M
M
de Grazia
U
U
Spinsanti
P
P
Mercola
D
D
Faggioni
A
A
Frati
L
L
Adamson
E D
ED
Ragona
G
G
D001402:B-Lymphocytes / Q000166:cytology / Q000821:virology; D002455:Cell Division; D002461:Cell Line, Transformed; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D051766:Early Growth Response Protein 1; D015967:Gene Expression Regulation, Viral; D006566:Herpesviridae Infections / Q000378:metabolism; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000502:physiology; D006801:Humans; D017874:Immediate-Early Proteins; D008213:Lymphocyte Activation; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D012333:RNA, Messenger / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation; D017735:Virus Latency
D004268:DNA-Binding Proteins; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D017874:Immediate-Early Proteins; D012333:RNA, Messenger; D014157:Transcription Factors