Page 8 - F. Cell biology

[F. Cell biology-4]

PRMT1 upregulates c-Fos-mediated AP-1 activity by

regulating the stability of c-Fos via autophagy blockade

Chaoran Song¹, Yo Han Hong¹, Jieun Oh¹, Wooram Choi¹, Han Gyung Kim¹, Doek Jeong¹, Long You¹,

Jae Youl Cho¹

¹Integrative Biotechnology, Sungkyunkwan University, suwon 16419, Korea

Protein arginine methyltransferase 1 (PRMT1) is methyltransferase to regulate various cellular processes via

methylation or other mechanism. AP-1, a heterodimeric protein transcription factor, is closely related to the
regulation of cellular processes such as cell differentiation, proliferation, and apoptosis. As an important subunit of

AP-1,c-Fos forms AP-1 through dimerization with other subunits. In this study, we found PRMT1 regulated c-Fos
thus enhanced AP-1 activity. The co-location of c-Fos and PRMT1 was in cytosol, implying that c-Fos is non-histone

substrate of PRMT1. Mitogen-associated protein kinases (MAPKs) and nuclear translocation of c-Fos did not altered
the upregulated AP-1. However, cycloheximide (CHX) chase assay showed that PRMT 1 extended retention time of

c-Fos. Upon 3-MA treatment, c-Fos and PRMT1-mediated AP-1 activity was increasingly ascended. Furthermore, c-
Fos expression level was downregualted when PRMT1 is knockdown. AP-1 activity was diminished when c-Fos was

transfected with PRMT1 dominant negative (DN). Additionally, the ectopic expression of c-Fos and PRMT1 increased
the methylated arginines (mme-R and adme-R). Therefore, PRMT1-mediated c-Fos methylation modulated c-Fos

stability resulting in enhancement of c-Fos activity.