title: A naturally occurring 4-bp deletion in the intron 4 of p53 creates a spectrum of novel p53 isoforms with anti-apoptosis function.
abstract: p53 functions as a tumor suppressor by transcriptionally regulating the expression of genes involved in controlling cell proliferation or apoptosis. p53 and its isoform Δ133p53/Δ113p53 form a negative regulation loop in that p53 activates the expression of Δ133p53/Δ113p53 while Δ133p53/Δ113p53 specifically antagonizes p53 apoptotic activity. This pathway is especially important to safeguard the process of embryogenesis because sudden activation of p53 by DNA damage signals or developmental stress is detrimental to a developing embryo. Here we report the identification of five novel p53 isoforms. p53β is generated due to alternative splicing of the intron 8 of p53 while the other four, namely, TA2p53, TA3p53, TA4p53 and TA5p53, result from the combination of alternative splicing of intron 1 (within intron 4 of the p53 gene) of the Δ113p53 gene and a naturally occurring CATT 4 bp deletion within the alternative splicing product in zebrafish. The CATT 4 bp deletion creates four translation start codons which are in-frame to the open reading frame of Δ113p53. We also show that TAp53 shares the same promoter with Δ113p53 and functions to antagonize p53 apoptotic activity. The identification of Δ113p53/TA2/3/4/5p53 reveals a pro-survival mechanism which operates robustly during embryogenesis in response to the DNA-damage condition.
authors.affiliation: MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Shi
authors.affiliation: MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Tao
authors.affiliation: MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China.
authors.forename: Delai
authors.initials: D
authors.lastname: Huang
authors.affiliation: College of Life Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Ou
authors.affiliation: College of Life Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058, China pengjr@zju.edu.cn.
authors.forename: Jinrong
authors.initials: J
authors.lastname: Peng
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000235:genetics* / Q000378:metabolism; D007438:Introns; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D020033:Protein Isoforms; D016159:Tumor Suppressor Protein p53; D029961:Zebrafish Proteins; C571228:tp53 protein, zebrafish