Overview:

c-Jun is a proto-oncogene that forms a complex with c-Fos which regulates transcription from promoters containing AP-1 activation elements (1). c-Jun has specific DNA binding activity and following in vitro translation, c-Jun binds as a homodimer to the AP-1 DNA site. The transactivating function of c-Jun is acutely regulated by a wide variety of cellular signals via modulation of phosphorylation of two serines (63 and 73). Jun N-terminal domain kinases (JNKs), are responsible for mediating S63/73 phosphorylation on c-Jun in response to a variety of cellular stimuli including TNF-a, heat stress and u.v. light (2).

References:

1.Halazonetis, T D. et al: c-Jun dimerizes with itself and with c-Fos, forming complexes of different DNA binding affinitie. Cell. 1988 Dec 2; 55(5):917-24.

2.Dai, T. et al: Stress-activated protein kinases bind directly to the delta domain of c-Jun in resting cells: implications for repression of c-Jun function. Oncogene. 1995 Mar 2; 10(5):849-55.