Project description:Transcriptional regulation of developmentally controlled genes is at the heart of differentiation and organogenesis. In this study, we have performed global genomic analyses in murine embryonic stem (ES) cells and in human cells in response to activation signals. We have identified an essential role for the ELL/P-TEFbcontaining Super Elongation Complex (SEC) in the regulation of gene expression including several genes bearing paused RNA polymerase II (Pol II). Paused Pol II has been proposed to be associated with loci that respond rapidly to environmental stimuli. However, our studies in ES cells have also identified a requirement for SEC at genes without preloaded Pol II, which also respond dynamically to differentiation signals. Our findings suggest that SEC is a major class of active P-TEFb-containing complexes required for transcriptional activation in response to environmental cues such as differentiation signals. Examination of ELL2, AFF4, and Pol II before and after activation signals in two cell types.

2011-07-19 | E-GEOD-30267 | biostudies-arrayexpress

Gene target specificity of the Super Elongation Complex (SEC) family: How HIV-1 Tat employs selected SEC members to activate viral transcription

Project description:The AF4/FMR2 proteins AFF1 and AFF4 act as a scaffold to assemble the Super Elongation Complex (SEC) that strongly activates transcriptional elongation of HIV-1 and cellular genes. Although they can dimerize, it is unclear whether the dimers exist and function within a SEC in vivo. Furthermore, it is unknown whether AFF1 and AFF4 function similarly in mediating SEC-dependent activation of diverse genes. Providing answers to these questions, our current study shows that AFF1 and AFF4 reside in separate SECs that display largely distinct gene target specificities. While the AFF1-SEC is more potent in supporting HIV-1 transactivation by the viral Tat protein, the AFF4-SEC is more important for HSP70 induction upon heat shock. The functional difference between AFF1 and AFF4 in Tat-transactivation has been traced to a single amino acid variation between the two proteins, which causes them to enhance the affinity of Tat for P-TEFb, a key SEC component, with different efficiency. Finally, genome-wide analysis confirms that the genes regulated by AFF1- and AFF4-SEC are largely non-overlapping and perform distinct functions. Thus, the SEC represents a family of related complexes that exist to increase the regulatory diversity and gene control options during transactivation of diverse cellular and viral genes. RNA-seq in HeLa cells of wild-type and after RNAi of AFF1 or AFF4.

2015-05-20 | E-GEOD-69021 | biostudies-arrayexpress

Super Elongation Complex (SEC) and global genomic analyses in murine embryonic stem (ES) cells and in human cells in response to activation signals.

2011-07-19 | GSE30267 | GEO

The super elongation complex family of RNA polymerase II elongation factors: gene target specificity and transcriptional output.

Project description: Not available

| S-EPMC3434493 | biostudies-literature

The Super Elongation Complex mediates phase transition of SPT5 during transcriptional pause release

Project description: Not available

| S-SCDT-10_15252-EMBR_202255699 | biostudies-other