Ubinuclein, a novel nuclear protein interacting with cellular and viral transcription factors.
The major target tissues for Epstein-Barr virus (EBV) infection are B lymphocytes and epithelial cells of the oropharyngeal zone. The product of the EBV BZLF1 early gene, EB1, a member of the basic leucine-zipper family of transcription factors, interacts with both viral and cellular promoters and transcription factors, modulating the reactivation of latent EBV infection. Here, we characterize a novel cellular protein interacting with the basic domains of EB1 and c-Jun, and competing of their binding to the AP1 consensus site. The transcript is present in a wide variety of human adult, fetal, and tumor tissues, and the protein is detected in the nuclei throughout the human epidermis and as either grainy or punctuate nuclear staining in the cultured keratinocytes. The overexpression of tagged cDNA constructs in keratinocytes revealed that the NH(2) terminus is essential for the nuclear localization, while the central domain is responsible for the interaction with EB1 and for the phenotype of transfected keratinocytes similar to terminal differentiation. The gene was identified in tail-to-tail orientation with the periplakin gene (PPL) in human chromosome 16p13.3 and in a syntenic region in mouse chromosome 16. We designated this novel ubiquitously expressed nuclear protein as ubinuclein and the corresponding gene as UBN1.
Aho
S
S
Department of Dermatology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA. sirpa@aho@mail.tju.edu
Buisson
M
M
Pajunen
T
T
Ryoo
Y W
YW
Giot
J F
JF
Gruffat
H
H
Sergeant
A
A
Uitto
J
J
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure; D002478:Cells, Cultured; D002874:Chromosome Mapping; D002885:Chromosomes, Human, Pair 16; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004817:Epidermis / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D005333:Fetus; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D015603:Keratinocytes / Q000502:physiology* / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D051179:Plakins; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D014764:Viral Proteins / Q000378:metabolism
C063676:BZLF1 protein, Herpesvirus 4, Human; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C491674:PPL protein, human; D051179:Plakins; C110037:Ppl protein, mouse; D015534:Trans-Activators; D014157:Transcription Factors; C406814:UBN1 protein, human; D014764:Viral Proteins