p73 is a p53 family transcription factor. Due to the presence in the 5' flanking region of two promoters, there are two N-terminal variants, TAp73, which retains a fully active transactivation domain (TA), and ΔNp73, in which the N terminus is truncated. In addition, extensive 3' splicing gives rise to at least seven distinctive isoforms; TAp73-selective knockout highlights its role as a regulator of cell death, senescence and tumor suppressor. ΔNp73-selective knockout, on the other hand, highlights anti-apoptotic function of ΔNp73 and its involvement in DNA damage response. In this work, we investigated the expression pattern of murine p73 C-terminal isoforms. By using a RT-PCR approach, we were able to detect mRNAs of all the C-terminal isoforms described in humans. We characterized their in vivo expression profile in mouse organs and in different mouse developmental stages. Finally, we investigated p73 C-terminal expression profile following DNA damage, ex vivo after primary cultures treatment and in vivo after systemic administration of cytotoxic compounds. Overall, our study first elucidates spatio-temporal expression of mouse p73 isoforms and provides novel insights on their expression-switch under triggered conditions.
p73 is a p53 family transcription factor . Due to the presence in the 5 ' flanking region of two promoters , there are two N - terminal variants , TAp73 , which retains a fully active transactivation domain ( TA ) , and ΔNp73 , in which the N terminus is truncated . In addition , extensive 3 ' splicing gives rise to at least seven distinctive isoforms ; TAp73-selective knockout highlights its role as a regulator of cell death , senescence and tumor suppressor . ΔNp73-selective knockout , on the other hand , highlights anti - apoptotic function of ΔNp73 and its involvement in DNA damage response . In this work , we investigated the expression pattern of murine p73 C - terminal isoforms . By using a RT - PCR approach , we were able to detect mRNAs of all the C - terminal isoforms described in humans . We characterized their in vivo expression profile in mouse organs and in different mouse developmental stages . Finally , we investigated p73 C - terminal expression profile following DNA damage , ex vivo after primary cultures treatment and in vivo after systemic administration of cytotoxic compounds . Overall , our study first elucidates spatio - temporal expression of mouse p73 isoforms and provides novel insights on their expression - switch under triggered conditions .
How many TAp73 isoforms have been identified in humans?
How many TAp73 isoforms have been identified in humans ?
seven
seven 7