DNA dC->dU-editing enzyme APOBEC-3B; phorbolin-1-related protein; phorbolin-2/3 (APOBEC3B)

Function

• probable DNA cytidine deaminase
• role in foreign DNA clearance
• may provide cellular innate resistance to a specific panel of genetic invaders including endogenous retroelements & a subset of viruses
• binds to apoB & AU-rich RNAs
• interacts with APOBEC3G
• does not interact with APOBEC1
• resricts expression or activity of Long Interspersed Element-1

cytidine + H2O = uridine + NH3

Cofactor: Zn+2

Structure

• homodimer
• belongs to the cytidine & deoxycytidylate deaminase family

Alternative splicing

named isoforms=2

Expression

• expressed at high & moderate levels in peripheral blood leukocytes, spleen, testes, heart, thymus, prostate & ovary
• also expressed at low levels in several other tissues
• phorbol 12-myristate 13-acetate (PMA) induces overexpression in keratinocytes

Comparative biology

• expressed at higher levels in human stem cells relative to other primate stem cells

Notes

• one of 7 related genes or pseudogenes found in a cluster, thought to result from gene duplication, on chromosome 22

More general terms

• DNA dC->dU-editing enzyme (phorbolin)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=9582
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:9582
• OMIM: https://mirror.omim.org/entry/607110
• UniProt: http://www.uniprot.org/uniprot/Q9UH17.html