Gene Expression

  • Home

SAGA Complex

In eukaryotes, the expression of protein-coding genes involves the integration of cellular signals, chromatin modification, and assembly of the transcription pre-initiation complex (PIC) that loads RNA polymerase II onto the core promoter. PIC formation is initiated by recruitment of the TATA-binding protein (TBP) to the promoter by protein complexes containing TBP-associated factors (TAFs) that interact [...]


Eukaryotic transcription of protein-coding genes requires the assembly of a Pre-Initiation Complex (PIC) at the core promoter. This large macromolecular complex includes RNA Polymerase II (RNA Pol II) and several general transcription factors. The factor that nucleates the assembly of the PIC is TFIID, a multi-subunit complex containing the TATA-binding protein (TBP) and several TBP-associated [...]


TFIIH is a large molecular complex that is essential for transcription initiation by RNA Pol II and the Nucleotide Excision DNA Repair (NER) pathway. Structural studies in our lab initially unraveled the molecular architecture of the TFIIH core complex, showing how the two ATP-consuming subunits, XPD and XPB are integrated and regulated by other structural [...]

Gene Silencing/PRC2

Polycomb Repressive Complex 2 (PRC2) trimethylates histone H3K27 to silence specific genes. It’s role is especially critical during development and for the maintenance of cell identity. In spite of its biological importance, when we began working on PRC2 little was known about the complex’s architecture and subunit organization. Prior to the resolution revolution, we reconstituted a [...]

Transcription initiation/PIC

The accurate initiation of transcription requires the assembly of a pre-initiation complex (PIC) that include TFIID, TFIIA, TFIIB, TFIIE, TFIIF, TFIIH and RNA pol II. Regulation is achieved by gene specific activators and repressors, cofactor complexes that mediate the interaction of the general machinery with sequence-specific activators, and protein complexes involved in the modification or [...]