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  • The EMBO Journal (1998) 17, 5015 - 5025
  • doi:10.1093/emboj/17.17.5015

A novel p53-inducible gene coding for a microtubule-localized protein with G2-phase-specific expression

René Utrera1,2,5, Licio Collavin1,5, Dejan Lazarevic acute1,5, Domenico Delia3 and Claudio Schneider1,4

  1. Laboratorio Nazionale Consorzio Interuniversitario Biotecnologie, AREA Science Park, Padriciano 99, 34012 Trieste, Italy
  2. Present address: Departamento Biologia Celular, Universidad Simon Bolivar, Apartado 89.000, Valle de Sartenejas, Caracas 1081-A, Venezuela
  3. Istituto Nazionale Tumori, Div. Oncologia Sperimentale A, Via G. Venezian 1, 20133 Milano, Italy
  4. Dipartimento Scienze e Tecnologie Biomediche, Universita' degli Studi di Udine, p.le Kolbe 1, 33100 Udine, Italy
  5. R.Utrera, L.Collavin and D.Lazarevic acute contributed equally to this work

Correspondence to:

Claudio Schneider, E-mail: schneide@cib.area.trieste.it

Received 27 March 1998; Accepted 3 July 1998; Revised 26 June 1998

Wild-type (wt) p53 can act as a sequence-specific transcriptional activator and it is believed that p53 elicits at least part of its biological effects by regulating the expression of specific target genes. By using a differential subtractive hybridization approach in a murine cell line stably transfected with a temperature-sensitive p53 mutant (Val135), we isolated a set of genes markedly induced by wt p53. One of them, provisionally named B99, was further characterized; its transcriptional induction was dependent on wt p53 function and the corresponding protein product was shown to accumulate after DNA damage in different cell types. Immunofluorescence analysis located the B99 protein to the microtubule network. Flow cytometry revealed that upon activation of p53 function the endogenous B99 protein was selectively induced in the G2 fraction of the cell population. When B99 was ectopically expressed in p53-null murine fibroblasts, B99-transfected cells displayed an increased fraction with a 4N DNA content, indicative of interference with G2 phase progression. Taken together these data suggest that B99 might play a role in mediating specific biological activities of wt p53 during the G2 phase.

  • Keywords:

    • G2-specific,
    • microtubule-localized protein,
    • p53,
    • p53-induced gene,
    • Val5 fibroblasts