CAP10

Putative lipopolysaccharide-modifying enzyme.

• SMART accession number: SM00672
• Description: -
• Interpro abstract (IPR006598):

  The CAP10 domain is found in glycosyltransferases from animals, plants and fungi. Rumi is a Drosophila protein with a CAP10 domain that functions as a protein O-glucosyltransferase. In human and mouse, three potential homologues exist: one with a high degree of identity to Drosophila Rumi (52%), and two others with lower degrees of identity but including a CAP10 domain (KDELC1 and KDELC2) [ (PUBMED:21949356) ]. Rumi catalyzes the transfer of glucose and/or xylose from UDP-glucose and UDP-xylose, respectively, to a serine within the consensus Cys-Xaa-Ser-Xaa-Pro-Cys) in epidermal growth factor repeats, such as those found in coagulation factors F7, F9 and NOTCH proteins. Notch signaling is regulated by Notch glucosylation and glucosylation is required for the correct folding and cleavage of Notch [ (PUBMED:18243100) (PUBMED:21490058) ].

  CAP10 from Cryptococcus neoformans encodes a xylosyltransferase [ (PUBMED:24751576) ]. This pathogenic fungus, which most commonly affects the central nervous system and causes fatal meningoencephalitis primarily in patients with AIDS, produces a thick extracellular polysaccharide capsule which is well recognised as a virulence factor. The CAP10 domain is required for capsule formation and virulence [ (PUBMED:10482503) ]. The capsule is primarily made of two xylose-containing polysaccharides, glucuronoxylomannan and galactoxylomannan, and the glycosyltransferase transfers xylose to alpha-1,3-dimannoside in a beta-1,2-linkage [ (PUBMED:17430900) ].

There are 5522 CAP10 domains in 5510 proteins in SMART's nrdb database.

Cellular role (predicted cellular role)

Binding / catalysis: Lipopolysaccharide-modification?

Literature (relevant references for this domain)

Primary literature is listed below; Automatically-derived, secondary literature is also avaliable.

• Chang YC, Kwon-Chung KJ
• Isolation, characterization, and localization of a capsule-associatedgene, CAP10, of Cryptococcus neoformans.
• J Bacteriol. 1999; 181: 5636-43

Cryptococcus neoformans is a pathogenic fungus which most commonly affectsthe central nervous system and causes fatal meningoencephalitis primarilyin patients with AIDS. This fungus produces a thick extracellularpolysaccharide capsule which is well recognized as a virulence factor.Here, we describe the isolation and characterization of a novel gene,CAP10, which is required for capsule formation. Complementation of theacapsular cap10 mutant produced an encapsulated strain and the deletion ofCAP10 from a wild strain resulted in an acapsular phenotype. The molecularmass of the hemagglutinin epitope-tagged Cap10p is about 73 kDa, which issimilar to the size predicted from sequence analysis. When CAP10 was fusedwith a hybrid green fluorescent protein construct, the fluorescencesignals appeared as patches in the cytoplasm. Using a reporter geneconstruct, we found that CAP10 was expressed at high levels inlate-stationary-phase cells. In addition, we found that the expressionlevels of CAP10 are modulated by the transcriptional factor STE12alpha.Deletion of STE12alpha downregulated the expression levels of CAP10 whileoverexpression of STE12alpha upregulated the expression levels of CAP10.Animal model studies indicate that deletion of the CAP10 gene results inthe loss of virulence, and complementation of the acapsular phenotype ofcap10 restores virulence. Thus, CAP10 is required for capsule formationand virulence.

Structure (3D structures containing this domain)

3D Structures of CAP10 domains in PDB

PDB code	Title
5f84	5F84
5f85	5F85
5f86	5F86
5f87	5F87

Links (links to other resources describing this domain)

• INTERPRO: IPR006598