Multiple complexes involved in tyrosine hydroxylase mRNA stability in rat adrenal medulla, after reserpine stimulation.
A 28-nucleotide sequence within the 3'-untranslated region (3'UTR) of tyrosine hydroxylase (TH) mRNA has been suggested to influence the turnover rate of the TH messenger in vitro (W. R. Paulding and M. F. Czyzyk-Krzeska, 1999, J. Biol. Chem. 274, 2532-2538). In this study, we show that treatment with reserpine, a catecholamine-depleting drug which increases the stability of TH mRNA, allows the binding of a cytosolic protein to this 28-mer site in the TH 3'UTR in the rat adrenal medulla. An ex vivo kinetic analysis shows that the resulting 54-kDa ribonucleoprotein is early induced by reserpine. However, the formation of this complex is not coupled with the upregulation of TH mRNA, indicating that this 54-kDa complex could not be the unique factor accountable for the long-term stabilization of the TH messenger. Following this result we found that several other cis-acting elements, located in single-stranded stem loops within the secondary structure of TH 3'UTR, formed multiple complexes (43, 54, and 105 kDa) with cytosolic, polysome-associated, and also nuclear proteins. Our findings demonstrate that the messenger stability does not depend solely on the formation of a unique RNA-protein complex, but involves mechanisms with higher complexity implicating the interactions between posttranscriptional, nuclear RNA export, and translational processes.
Alterio
J
J
Laboratoire de Génétique Moléculaire de la Neurotransmission et des Processus Neurodégénératifs, CNRS UMR C9923, Bâtiment CERVI, Hôpital de la Pitié Salpêtrière, 83, Boulevard de l'Hôpital, Paris, 75013, France.
Mallet
J
J
Biguet
N F
NF
D020413:3' Untranslated Regions / Q000378:metabolism; D000313:Adrenal Medulla / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002395:Catecholamines / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D046911:Macromolecular Substances; D008297:Male; D009690:Nucleic Acid Conformation; D011132:Polyribosomes / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics; D011506:Proteins / Q000378:metabolism; D020871:RNA Stability / Q000187:drug effects*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012110:Reserpine / Q000494:pharmacology*; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics / Q000378:metabolism*
D020413:3' Untranslated Regions; D002395:Catecholamines; D046911:Macromolecular Substances; D011506:Proteins; D012333:RNA, Messenger; D012110:Reserpine; D014446:Tyrosine 3-Monooxygenase