title: ΔNp63α controls YB-1 protein stability: evidence on YB-1 as a new player in keratinocyte differentiation.
abstract: Y-box binding protein 1 (YBX-1 or YB-1) is an oncoprotein that promotes replicative immortality, tumor cell invasion and metastasis. The increase in the abundance of YB-1 in the cell or YB-1 translocation from the cytoplasm to the nucleus is characteristic of malignant cell growth. We have previously reported that ΔNp63α, a transcription factor that is known to play a pivotal role in keratinocyte proliferation and differentiation, promotes YB-1 nuclear accumulation. Here, we show that YB-1 is highly expressed in proliferating keratinocytes and is down-regulated during keratinocyte differentiation. ΔNp63α reduces YB-1 protein turnover and leads to accumulation of ubiquitin-conjugated YB-1 into the nucleus. Reduction of YB-1 protein level, following treatment with a DNA-damaging agent, is inhibited by ΔNp63α suggesting that YB-1 and ΔNp63α interplay can support keratinocyte proliferation and protect cells from apoptosis under genotoxic stress.
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Orsola
authors.initials: O
authors.lastname: di Martino
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Annaelena
authors.initials: A
authors.lastname: Troiano
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Guarino
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pollice
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Vivo
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Girolama
authors.initials: G
authors.lastname: La Mantia
authors.affiliation: Department of Biology, University of Naples 'Federico II', 80126, Naples, Italy.
authors.forename: Viola
authors.initials: V
authors.lastname: Calabrò
mesh_terms: D002453:Cell Cycle; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D015536:Down-Regulation; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism; D055550:Protein Stability; D014157:Transcription Factors / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000378:metabolism*; D051840:Y-Box-Binding Protein 1 / Q000737:chemistry* / Q000378:metabolism
chemical_list: C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D051840:Y-Box-Binding Protein 1; C070856:YBX1 protein, human