| Primary Identifier | IPR048263 | Type | Family |
| Short Name | Arb2 |
| description | Members of this entry contain the Arb2 domain that gets its name from S. pombe Argonaute-binding protein 2 (Arb2), which is the orthologue of the vertebrate cotranscriptional regulator ARB2A (also known as FAM172 family) []. Human FAM172A protein is associated with CHARGE syndrome, a severe multi-organ developmental disorder mainly affecting derivatives of cranial and cardiac neural crest cells (NCCs). CHARGE syndrome has been suggested to be a spliceosomopathy, due to perturbation of chromatin-mediated alternative splicing [, ]. FAM172A and its homologues contain a large Arb2 domain split into two halves by a classical bipartite NLS that helps to stabilise the chromatin-spliceosome interface as part of a complex that includes CHD7 and AGO2 []. It has been suggested that FAM172A can connect the alternative splicing machinery to specific transcribed regions [, ]. S. pombe Arb2 is a member of the argonaute siRNA chaperone (ARC) complex which is required for histone H3K9 methylation, heterochromatin assembly and siRNA generation. The Arb2 domain has clear homology to ��/��-hydrolases but it lacks the catalytic triad of these enzymes. |
