Altered sumoylation of p63alpha contributes to the split-hand/foot malformation phenotype.
p63 mutations have been identified in several developmental abnormalities, including split-hand/foot malformation (SHFM). In this study, we demonstrate that the C-terminal domain of p63alpha associates with the E2 ubiquitin conjugating enzyme, Ubc9. A p63alpha mutation, Q634X, which naturally occurs in SHFM modulated the interaction of p63alpha with Ubc9 in yeast genetic assay. Furthermore, Ubc9 catalyzed the conjugation of p63alpha with small ubiquitin modifier-1 (SUMO-1), which covalently modified p63alpha in vitro and in vivo at two positions (K549E and K637E), each situated in a SUMO-1 modification consensus site (phiKXD/E). In addition, p63alpha mutations (K549E and K637E) abolished sumoylation of p63alpha, dramatically activated transactivation properties of TAp63alpha, and inhibited the dominant-negative effect of DeltaNp63alpha. These p63alpha mutations also affected the transcriptional regulation of gene targets involved in bone and tooth development (e.g., RUNX2 and MINT) and therefore might contribute to the molecular mechanisms underlying the SHFM phenotype.
Huang
Yi-Ping
YP
Department of Dermatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Wu
Guojun
G
Guo
Zhongmin
Z
Osada
Motonobu
M
Fomenkov
Tanya
T
Park
Hannah Lui
HL
Trink
Barry
B
Sidransky
David
D
Fomenkov
Alexey
A
Ratovitski
Edward A
EA
D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins; D005347:Fibroblasts / Q000166:cytology; D005532:Foot Deformities, Congenital / Q000378:metabolism*; D005786:Gene Expression Regulation; D016147:Genes, Tumor Suppressor; D006228:Hand Deformities, Congenital / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D010750:Phosphoproteins / Q000737:chemistry / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D025842:SUMO-1 Protein / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors; D014158:Transcription, Genetic; D025521:Tumor Suppressor Proteins; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism; D000098843:Ubiquitin-Conjugating Enzyme UBC9
D004268:DNA-Binding Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D025842:SUMO-1 Protein; C115051:TP63 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D044763:Ubiquitin-Conjugating Enzymes; D000098843:Ubiquitin-Conjugating Enzyme UBC9