cd16671: RING-H2_DTX1_4 (this model, PSSM-Id:319585 is obsolete and has been replaced by 438333)
RING finger, H2 subclass, found in E3 ubiquitin-protein ligase deltex1 (DTX1), deltex4 (DTX4), and similar proteins
DTX1 is a mammalian homolog of Drosophila Deltex that is a ubiquitously expressed cytoplasmic ubiquitin E3 ligase that mediates Notch activation in Drosophila. It functions as a Notch downstream transcription regulator that mediates a Notch signal to block differentiation of neural progenitor cells. DTX1 interacts with the transcription coactivator p300 and inhibits transcription activation mediated by the neural specific transcription factor MASH1. It is also a transcription target of nuclear factor of activated T cells (NFAT) and participates in T cell anergy and Foxp3 protein level maintenance in vivo. Moreover, Deltex1 appears to promote B-cell development at the expense of T-cell development. It also promotes protein kinase C theta degradation and sustains Casitas B-lineage lymphoma expression. DTX4, also known as RING finger protein 155, shares the highest degree of sequence similarity with DTX1 and likely interacts with the intracellular domain of Notch as well. Both DTX1 and DTX4 contain N-terminal two Notch-binding WWE domains that physically interact with the Notch ankyrin domains, a proline-rich motif that shares homology with SH3-binding domains, and a C3H2C3-type RING-H2 finger at the C-terminus. They also harbor two nuclear localization signals.