Rezacova, M. | Search bioRxiv

bioRxiv2019

The 9aaTAD activation domains in the four Yamanaka Oct4, Sox2, Myc, and Klf4 transcription factors essential during the stem cell development

Somatic cells can be reprogrammed by the Yamanaka factors Oct4, Sox2, Myc and Klf4 activators into induced pluripotent stem cells. Throughout their genome, the Oct4, Sox2 and Klf4 cooperate with mediators of transcription, where the DNA binding sites serve as scaffolds for the phase-separated transcriptional condensates at distinct genome loci. In this study, we identified the 9aaTAD activation domains as the common interaction interface of the Yamanaka factors for transcription machinery. All four activation domains were identified by our online 9aaTAD prediction service and experimentally confirmed as strong activators of transcription. We considered the mediator interactions granted by 9aaTADs as part of the Yamanaka factors ability to reprogram cell fate. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=64 SRC="FIGDIR/small/876706v1_ufig1.gif" ALT="Figure 1"> View larger version (13K): org.highwire.dtl.DTLVardef@c5105forg.highwire.dtl.DTLVardef@1b5e910org.highwire.dtl.DTLVardef@1d83c2aorg.highwire.dtl.DTLVardef@1561881_HPS_FORMAT_FIGEXP M_FIG C_FIG

genetics↗

bioRxiv2017

Gal4 activation domain 9aaTAD could be inactivated by adjacent mini-inhibitory domain and reactivated by distal re-activation domain

The characterisation of the activation domains started three decades ago with Gcn4 and Gal4 activators. The amorphous character of the activation domains strongly hindered their definition. Moreover, during the attempts to localise the Gal4 activation domain, the artificial peptides, an unintended consequence of cloning, were responsible for artificial transcriptional activity of the several Gal4 constructs. These artefacts produced enormous experimental bias and misconception. The presence of inhibitory domains in some Gal4 constructs made the misperception even worse. Previously, we reported that the nine amino acid transactivation domain, 9aaTAD, is the exclusive activation domain in the Gal4 protein. The activation domain 9aaTAD could be identified in Gal4 paralogs Oaf1, Pip2, Pdr1, Pdr3 and other activators p53, E2A and MLL. Surprisingly, the activation domain 9aaTAD was reported as misconception for Gal4 activator. Here we demonstrated that small region of 10 amino acids adjacent to the Gal4 activation domain 9aaTAD is an inhibitory domain, which the authors included in their constructs. Moreover, we identified Gal4 region, which was able to the reverse the inhibitory effect. The 9aaTAD re-activation domain was localized to the 13 amino acid long region. In this report we clarified the numerous confusions and rebutted supposed 9aaTAD misconception.\n\nSummaryThe activation domain 9aaTAD has decisive function in Gal4 activation. Gal4 activation domain 9aaTAD could be inhibited by adjacent region of 10 amino acids. The inhibited Gal4 activation domain 9aaTAD could be reactivated by 13 amino acid long Gal4 region. The activation domains 9aaTAD could be identified by our 9aaTAD prediction algorithm, especially in the Gal4 family.

molecular biology↗