title: Identification and tissue distribution of novel KET/p63 splice variants.
abstract: The human p53 protein family comprises three members - p53, p63 and p73. Whereas only one p53 variant is known multiple isoforms of p63 and p73 have been described. Depending on the isoform p63 influences p53-responsive genes in a p53-like or -distinct manner. We have cloned multiple splice variants of keratinocyte transcription factor (KET), the rat ortholog of human p63. Several tissue specific variations of exon 1 resulting in different amino-terminal ends were identified. Transactivation properties of the splice variants inversely correlated with the length of the N-termini as determined by activation of the p53-responsive p21 promotor. Multiple KET isoforms are colocalized in different rat tissues. The amino-terminal truncated form DeltaNKETalpha is expressed in epithelial tissues, while expression of the most p53-like KET isotype TAKETgamma was detected in skeletal muscle. Expression of a major KET variant appears to be a cell-type specific rather than a differentiation specific phenomenon.
authors.affiliation: Institut für Zellbiochemie und Klinische Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Bamberger
authors.forename: H
authors.initials: H
authors.lastname: Schmale
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004268:DNA-Binding Proteins; D016147:Genes, Tumor Suppressor; D006801:Humans; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D012689:Sequence Homology, Nucleic Acid; D014018:Tissue Distribution; D015534:Trans-Activators; D014157:Transcription Factors; D015533:Transcriptional Activation; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D025521:Tumor Suppressor Proteins
chemical_list: C081876:CKAP4 protein, human; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D020033:Protein Isoforms; D012333:RNA, Messenger; C115051:TP63 protein, human; C108581:Tp63 protein, rat; D015534:Trans-Activators; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins