In fact, Hes3 expression marks a subpopulation of Sox2+ cells in many regions of the adult rat brain

ssociated with the IKK complex. The amino acids from position 210-215 of ZNF395 encode the sequence DSGSST, which is homologue to `DpSGXpS/T that functions as an IKK phosphorylation motif and binding site for the ubiquitin ligase -Trcp in some IKK substrates such as CBP, IB, p105, p100, -catenin and FOXO3a. We are currently testing whether ZNF395 is directly targeted by IKK. Our data suggest that IKK-activity is required for ZNF395 to activate transcription and Y-27632 dihydrochloride directs ZNF395 to ubiquitin-mediated degradation. The IKK-induced turnover of ZNF395 may contribute to promoter clearance to allow reinitiation of transcription. A similar regulation has been described for IRF3. IRF3 undergoes virus-dependent phosphorylation mediated by IKK/TBK1, which results in the nuclear translocation, DNA binding and increased transcriptional activation. Phosphorylation of IRF3 in response to virus infections also provides a signal for proteasomal degradation. Moreover, proteasomal degradation of both ZNF395 and IRF3 upon activation of an anti-viral response may also dampen the immediate early immune response and thus represent a negative regulation. Our results illustrate that the expression of ZNF395 is not affected in response to IFN-, but is induced by hypoxia. Correlatively, ZNF395 was found to be upregulated as part of a response to hypoxia in glioblastomas and neuroblastomas and in adipocytes. ZNF395 may be a direct target gene of HIF since its expression was modulated by overexpression or knockdown of HIF-1, and a ChIP-on-chip analysis identified two sites several kb upstream of the ZNF395 promoter bound by HIF-1 and HIF-2. We show that hypoxia does not affect IKK-mediated degradation of ZNF395, implying that ZNF395 induced by hypoxia is transcriptionally active. The results of the microarray also revealed an increased expression of four genes known to be associated with cancer upon induction of ZNF395. These include the 10884437 transcription factor MEF2C, found to be activated in a subset of T-acute lymphoblastic leukemia cell lines, CALCOCO1, that can act as a transcriptional co-activator for the androgen receptor and TCF/LEF in cooperation with -catenin, or MACC1, which is a key regulator of hepatocyte growth factor receptor signaling and was shown to predict colon cancer metastasis. Although further analysis is required to determine a functional role of ZNF395 in controlling the expression of these cancer-associated genes, it is possible that ZNF395 may also affect cancer growth by elevating the expression of these genes 17318643 in particular under conditions of hypoxia. Taken together, we show that ZNF395 is required for the full induction of several ISGs and is thus part of the innate immune response. This is supported by the observation that the transcriptional activity of ZNF395 depends on IKK signaling. Furthermore, the finding that the target genes of ZNF395 are involved in the innate immune response and cancer, implies that ZNF395 may support inflammation and cancer progression under hypoxia, which deserves further investigation. Acknowledgements We thank J. Hiscott, N. Grandvaux, H. Nakano and A. Roa for providing plasmids and Herbert Pfister and Zebulon Tolman for critical reading of the manuscript and helpful discussions. The actin cytoskeleton is a highly plastic structure with ability to rapidly remodel upon many extra- and intracellular cues. In epithelial-to-mesenchymal transition, epithelial cells dissociate their cell-cell junctions, and remode