Promoter architecture and response to a positive regulator of archaeal transcription.
The archaeal transcription apparatus is chimeric: its core components (RNA polymerase and basal factors) closely resemble those of eukaryotic RNA polymerase II, but the putative archaeal transcriptional regulators are overwhelmingly of bacterial type. Particular interest attaches to how these bacterial-type effectors, especially activators, regulate a eukaryote-like transcription system. The hyperthermophilic archaeon Methanocaldococcus jannaschii encodes a potent transcriptional activator, Ptr2, related to the Lrp/AsnC family of bacterial regulators. Ptr2 activates rubredoxin 2 (rb2) transcription through a bipartite upstream activating site (UAS), and conveys its stimulatory effects on its cognate transcription machinery through direct recruitment of the TATA binding protein (TBP). A functional dissection of the highly constrained architecture of the rb2 promoter shows that a 'one-site' minimal UAS suffices for activation by Ptr2, and specifies the required placement of this site. The presence of such a simplified UAS upstream of the natural rubrerythrin (rbr) promoter also suffices for positive regulation by Ptr2 in vitro, and TBP recruitment remains the primary means of transcriptional activation at this promoter.
Ouhammouch
Mohamed
M
Division of Biological Sciences and Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA. mouham@biomail.ucsd.edu
Langham
Geoffrey E
GE
Hausner
Winfried
W
Simpson
Anjana J
AJ
El-Sayed
Najib M A
NM
Geiduschek
E Peter
EP
D019843:Archaeal Proteins / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005288:Ferredoxins / Q000235:genetics / Q000378:metabolism; D019848:Gene Expression Regulation, Archaeal; D006422:Hemerythrin; D017015:Methanococcales / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012416:Rubredoxins / Q000235:genetics* / Q000378:metabolism; D016385:TATA Box; D035181:TATA-Box Binding Protein; D024363:Transcription Initiation Site; D014158:Transcription, Genetic
D019843:Archaeal Proteins; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D005288:Ferredoxins; D006422:Hemerythrin; C423032:Ptr2 protein, Methanococcus jannaschii; D012416:Rubredoxins; D035181:TATA-Box Binding Protein; C055857:rubrerythrins