The serum- and glucocorticoid-regulated kinase (SGK1) controls cell transformation and tumorprogression. SGK1 affects mitotic stability by regulating the expression of RANBP1/RAN. Here, wedemonstrate that SGK1 fluctuations indirectly modify the maturation of pre-miRNAs, by modulatingthe equilibrium of the RAN/RANBP1/RANGAP1 axis, the main regulator of nucleo-cytoplasmictransport. The levels of pre-miRNAs and mature miRNAs were assessed by qRT-PCR, in total extractsand after differential nuclear/cytoplasmic extraction. RANBP1 expression is the limiting step in theregulation of SGK1-SP1 dependent nuclear export. These results were validated in unrelated tumormodels and primary human fibroblasts and corroborated in tumor-engrafted nude mice. The levelsof pri-miRNAs, DROSHA, DICER and the compartmental distribution of XPO5 were documented.Experiments using RANGTP conformational antibodies confirmed that SGK1, through RANBP1,decreases the level of the GTP-bound state of RAN. This novel mechanism may play a role in theepigenomic regulation of cell physiology and fate.
SGK1 affects RAN/RANBP1/RANGAP1 via SP1 to play a critical role in pre-miRNA nuclear export: a new route of epigenomic regulation
Vincenzo Dattilo;Lucia D’antona;Cristina Talarico;Giada Catalogna;Rodolfo Iuliano;Cataldo Bianco;PERROTTI N;Rosario Amato
2017-01-01
Abstract
The serum- and glucocorticoid-regulated kinase (SGK1) controls cell transformation and tumorprogression. SGK1 affects mitotic stability by regulating the expression of RANBP1/RAN. Here, wedemonstrate that SGK1 fluctuations indirectly modify the maturation of pre-miRNAs, by modulatingthe equilibrium of the RAN/RANBP1/RANGAP1 axis, the main regulator of nucleo-cytoplasmictransport. The levels of pre-miRNAs and mature miRNAs were assessed by qRT-PCR, in total extractsand after differential nuclear/cytoplasmic extraction. RANBP1 expression is the limiting step in theregulation of SGK1-SP1 dependent nuclear export. These results were validated in unrelated tumormodels and primary human fibroblasts and corroborated in tumor-engrafted nude mice. The levelsof pri-miRNAs, DROSHA, DICER and the compartmental distribution of XPO5 were documented.Experiments using RANGTP conformational antibodies confirmed that SGK1, through RANBP1,decreases the level of the GTP-bound state of RAN. This novel mechanism may play a role in theepigenomic regulation of cell physiology and fate.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
