Archaea represent a highly diverse class of prokaryotic microorganisms capable of withstanding harsh environmental conditions such as extremes of temperature, pH, salinity and pressure; it is because of these properties that they are sometimes also referred to as “extremophiles”. Despite being prokaryotic, Archaea share a number of features with eukaryotes one of which is their transcriptional apparatus. Studies to date have shown that the 10-subunit RNA polymerase, TATA-binding protein (TBP) and transcription factor-B (TFB) altogether serve as minimal set of factors required to transcribe most Sulfolobus gene promoters. A number of other proteins have also been implicated in transcription but their roles in this process are not well understood. Using Sulfolobus as a model organism, we are studying mechanisms through which heat shock, DNA damage and oxidative stress are induced. Specifically, our goal is to identify factors that sense such stresses and to understand how they interact with the various components of transcription machinery to influence expression of their respective target genes.