New p63 targets in keratinocytes identified by a genome-wide approach.
p63 is a developmentally regulated transcription factor related to p53. It is involved in the development of ectodermal tissues, including limb, skin and in general, multilayered epithelia. The DeltaNp63alpha isoform is thought to play a 'master' role in the asymmetric division of epithelial cells. It is also involved in the pathogenesis of several human diseases, phenotypically characterized by ectodermal dysplasia. Our understanding of transcriptional networks controlled by p63 is limited, owing to the low number of bona fide targets. To screen for new targets, we employed chromatin immunoprecipitation from keratinocytes (KCs) coupled to the microarray technology, using both CpG islands and promoter arrays. The former revealed 96 loci, the latter yielded 85 additional genes. We tested 40 of these targets in several functional assays, including: (i) in vivo binding by p63 in primary KCs; (ii) expression analysis in differentiating HaCaT cells and in cells overexpressing DeltaNp63alpha; (iii) promoter transactivation and (iv) immunostaining in normal tissues, confirming their regulation by p63. We discovered several new specific targets whose functional categorization links p63 to cell growth and differentiation.
Viganò
M Alessandra
MA
Dipartimento di Scienze Biomolecolari e Biotecnologie, Universita' di Milano, Milano, Italy. alessandra.vigano@guest.unimi.it
Lamartine
Jérôme
J
Testoni
Barbara
B
Merico
Daniele
D
Alotto
Daniela
D
Castagnoli
Carlotta
C
Robert
Amèlie
A
Candi
Eleonora
E
Melino
Gerry
G
Gidrol
Xavier
X
Mantovani
Roberto
R
D000818:Animals; D019556:COS Cells; D002454:Cell Differentiation / Q000502:physiology*; D002522:Chlorocebus aethiops; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism*; D038081:Organogenesis / Q000502:physiology; D040081:Protein Array Analysis / Q000379:methods; D011485:Protein Binding / Q000502:physiology; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors; D015533:Transcriptional Activation / Q000502:physiology*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*
D004268:DNA-Binding Proteins; C115051:TP63 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins