EGF REGULATION OF SPECIFIC ENDORIBONUCLEASE ACTIVITY OF 26S PROTEASOMES FROM A431
CELLS: A POTENTIAL LINK BETWEEN SIGNAL TRANSDUCTION AND mRNA STABILITY
I. N. Evteeva, V. A. Kulichkova, A. D. Obukhova, A. G. Mittenberg, I. V. Volkova, Yu. B. Ermolaeva,
M. V. Toktarova, L. V. Teslenko, L. N. Cause, I. M. Konstantinova 1
Institute of Cytology RAS, St. Petersburg;
1 e-mail: ikonst@mail.cytspb.rssi.ru
For the first time it has been shown that RNase activity is induced under the influence of EGF on epidermoid
carcinoma cell line A431. Proteasomes from EGF-treated A431 cells destabilize the 3'-untransla-ted regions of
non-muscle b actin mRNA, creating a specific cleavage pattern. In addition, these particles have been shown to
specifically cleave Alu-containing informational RNA. The enzymatic activity under study has been shown to be
dependent on phosphorylation of proteasomal subunits and specifically and selectively regulated by Ca and Mg ions.
Proteasome involvement in the coordinated control of stability of specific messenger RNA molecules is suggested.
The endoribonuclease activity of 26S proteasomes can constitute a link between EGF signaling pathways and RNA
stability.
Key words: proteasomes, mRNA stability, interspersed repeats, ribonucleases, epidermal growth factor
Back
Contents
Main
|
