Project description:Microarray analysis was used to identify all cryptic promoters in the S. cerevisiae genome that are activated in spt6 and spt16 mutants. These experiments showed that cryptic initiation is widespread, occurring in approximately 1,000 genes. We generated 2 microarray profiles from fluor-reversed replicates of wild-type and spt6-1004 or spt16-197 mutants. See Cheung et al., (2008) in revision.
Project description:Microarray analysis was used to identify all cryptic promoters in the S. cerevisiae genome that are activated in spt6 and spt16 mutants. These experiments showed that cryptic initiation is widespread, occurring in approximately 1,000 genes.
Project description:FACT consists of two essential subunits Spt16 and Pob3 and is a histone chaperone. Depletion of Spt16 using a an spt16 mutant results in a global alteration of nucleosome positions as well as aberrant transcription. Here we show that the majority of nucleosomal changes at gene body upon Spt16 depletion are independent of gene activity, but correlates with cryptic gene transcription and are suppressed by inhibition of RNA Polymerase II activities. In addition, A small fraction of nucleosomal changes is resistant to Pol II inhibition, and Spt16 is enriched at this subgroup of nucleosomes. Moreover, nucleosomes surrounding the initiation sites of cryptic transcription in the spt16 mutant cells are more dynamic than other regions. These results support a model that Spt16 maintains nucleosome stability locally to inhibit the initiation from cryptic transcription, which that once initiated drives additional nucleosome loss upon Spt16 depletion.
