Orphan Nuclear Receptor, NR4A1 Restrains The Transcription Activation Of STAT3

STAT3 is an important member of the signal transducer and activator of transcription (STAT) family of transcription factors. In resting cells, STAT3 resides largely in the cytoplasm. Upon cytokine stimulation, It is activated and rapidly translocates to the nucleus, where it promotes the expression of the target genes. STAT3 plays a key role in tumor by regulating the target genes. During the subsequent period of signal decay, It is re-exported back to the cytoplasm in preparation for the next round of signaling. It is reported that many protein can interact with STAT3. We studied the interaction between STAT3 and NR4A1 by reporter gene assay. orphan nuclear receptor, NR4A1 plays a key role in the regulation of the cell cycle by its regulation of Target Protein' s expression, and NR4A1 also plays a key role in may illnesses just as cancer and diabetes. In our experiment NR4A1 and STAT3 were transfected into eukaryote HEK293. the effect of NR4A1 on Transcription Activity of STAT3 was tested. The resμLts showed that NR4A1 restrains the transcription activation of STAT3. the effect of STAT3 on transcription Activity of NR4A1 also was tested. The results showed that STAT3 restrains the transcription activation of NR4A1 too. but the effect of STAT3 to NR4A1 is more weaker than STAT3' s to NR4A1.In the second part of our experiment. The recombinant plasmid GST-STAT3-4 which is a truncation of STAT3 was transformed into E. coli JM109 and then induced to express a fussion protein by IPTG successfully. and we also renatured the intranuclear indusions of the fussion protein GST-STAT3-4...