Transactivation activity of Nur77 discriminates between Ca2+ and cAMP signals.
The orphan nuclear receptors Nur77 and Nurr1 are the members of the Nur77 family of transcription factors. We demonstrate that transcription of the Nur77 family genes was upregulated in PC12 cells following incubation with Ca2+ ionophore as well as cyclic AMP (cAMP) analog. On the other hand, cAMP analog induced strong increase, while Ca2+ ionophore induced weak increase in the transactivation activity of Nur77. We found that Nur77 and Nurr1 proteins were expressed in the nucleus following stimulation with cAMP analog but not after stimulation with Ca2+ ionophore. However, expression of Nur77 protein was increased in the cytoplasm of cells treated with Ca2+ ionophore. In conclusion, our results suggest that cAMP-induced and Ca2+-induced processes may differentially regulate activity of Nur77 at the level of translocation of Nur77 protein from the cytoplasm into the nucleus.
Klopotowska
Dagmara
D
Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigl 12, 53-114 Wroclaw, Poland.
Matuszyk
Janusz
J
Rapak
Andrzej
A
Gidzinska
Barbara
B
Cebrat
Malgorzata
M
Ziolo
Ewa
E
Strzadala
Leon
L
D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000235:genetics; D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects / Q000235:genetics*; D002467:Cell Nucleus / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000235:genetics*; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D015759:Ionomycin / Q000494:pharmacology; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D016716:PC12 Cells; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D011987:Receptors, Steroid / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics
D004268:DNA-Binding Proteins; C539820:Nr4a1 protein, rat; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D014157:Transcription Factors; D015759:Ionomycin; D000242:Cyclic AMP