Changes in the conformation of the interferon beta gene during differentiation and induction.

DNase I sensitivity was used to investigate the chromatin conformation of the interferon beta gene during differentiation of the mouse teratocarcinoma cell line PC13 . These cells do not produce interferon upon viral induction in their undifferentiated state, but do so on differentiation from stem cells to endoderm. Only in induced differentiated cells were the interferon beta genes digested by DNase I. A similar effect was seen in a line of human cells ( MG63 ) upon induction. We conclude that it is induction of interferon production that brings about the change in the DNase I sensitivity of these genes, rather than differentiation.