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Biology subjects

Pogson, A.

Publications and source records attributed to Pogson, A..

2 recordsLinked to original sources

Control of myogenesis by the E3 ubiquitin ligase CUL3-BTBD9

Metazoan development requires that cells adopt specific identities at the right time and place with-in an embryo. Central to the success of this process are posttranslational modifications that control the activity, stability or localization of crucial transducers of differentiation signals. During muscle development, modification of proteins with ubiquitin is known to play an important role, but the enzymatic machinery of ubiquitylation that drives myogenesis remains incompletely understood. Here, we identify CUL3BTBD9 as an E3 ubiquitin ligase that is essential for myogenesis in vitro. CUL3BTBD9 binds and ubiquitylates CAV1, the central component of caveolae that modulate insulin signaling during muscle formation. CUL3BTBD9 and CAV1 are required for insulin-dependent activation of the AKT kinase in myoblasts, thereby safeguarding the ability of muscle precursors to respond to insulin signals. Together, this work identifies CUL3BTBD9 as a regulator of myogenesis that acts by modulating plasma-membrane localized events critical for cell fate specification.

cell biology↗

DNA-guided transcription factor cooperativity shapes face and limb mesenchyme

Transcription factors (TFs) can define distinct cellular identities despite nearly identical DNA-binding specificities. One mechanism for achieving regulatory specificity is DNA-guided TF cooperativity. Although in vitro studies suggest it may be common, examples of such cooperativity remain scarce in cellular contexts. Here, we demonstrate how Coordinator, a long DNA motif comprised of common motifs bound by many basic helix-loop-helix (bHLH) and homeodomain (HD) TFs, uniquely defines regulatory regions of embryonic face and limb mesenchyme. Coordinator guides cooperative and selective binding between the bHLH family mesenchymal regulator TWIST1 and a collective of HD factors associated with regional identities in the face and limb. TWIST1 is required for HD binding and open chromatin at Coordinator sites, while HD factors stabilize TWIST1 occupancy at Coordinator and titrate it away from HD-independent sites. This cooperativity results in shared regulation of genes involved in cell-type and positional identities, and ultimately shapes facial morphology and evolution.

genomics↗