5f85

From Proteopedia

Crystal structure of Drosophila Poglut1 (Rumi) complexed with its substrate protein (EGF repeat) and UDP

Structural highlights

5f85 is a 2 chain structure with sequence from Drosophila melanogaster and Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.15Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

RUMI_DROME Protein O-glucosyltransferase. Catalyzes the reaction that attaches glucose through an O-glycosidic linkage to a conserved serine residue in epidermal growth factor-like repeats. Regulates Notch signaling by glucosylating Notch in the ER, glucosylation is required for the correct folding and cleavage of Notch.^[1]

Publication Abstract from PubMed

Rumi O-glucosylates the EGF repeats of a growing list of proteins essential in metazoan development, including Notch. Rumi is essential for Notch signaling, and Rumi dysregulation is linked to several human diseases. Despite Rumi's critical roles, it is unknown how Rumi glucosylates a serine of many but not all EGF repeats. Here we report crystal structures of Drosophila Rumi as binary and ternary complexes with a folded EGF repeat and/or donor substrates. These structures provide insights into the catalytic mechanism and show that Rumi recognizes structural signatures of the EGF motif, the U-shaped consensus sequence, C-X-S-X-(P/A)-C and a conserved hydrophobic region. We found that five Rumi mutations identified in cancers and Dowling-Degos disease are clustered around the enzyme active site and adversely affect its activity. Our study suggests that loss of Rumi activity may underlie these diseases, and the mechanistic insights may facilitate the development of modulators of Notch signaling.

Structural analysis of Notch-regulating Rumi reveals basis for pathogenic mutations.,Yu H, Takeuchi H, Takeuchi M, Liu Q, Kantharia J, Haltiwanger RS, Li H Nat Chem Biol. 2016 Sep;12(9):735-40. doi: 10.1038/nchembio.2135. Epub 2016 Jul, 18. PMID:27428513^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Acar M, Jafar-Nejad H, Takeuchi H, Rajan A, Ibrani D, Rana NA, Pan H, Haltiwanger RS, Bellen HJ. Rumi is a CAP10 domain glycosyltransferase that modifies Notch and is required for Notch signaling. Cell. 2008 Jan 25;132(2):247-58. doi: 10.1016/j.cell.2007.12.016. PMID:18243100 doi:http://dx.doi.org/10.1016/j.cell.2007.12.016
↑ Yu H, Takeuchi H, Takeuchi M, Liu Q, Kantharia J, Haltiwanger RS, Li H. Structural analysis of Notch-regulating Rumi reveals basis for pathogenic mutations. Nat Chem Biol. 2016 Sep;12(9):735-40. doi: 10.1038/nchembio.2135. Epub 2016 Jul, 18. PMID:27428513 doi:http://dx.doi.org/10.1038/nchembio.2135