Apolipoprotein B mRNA Editing Enzyme Catalytic Polypeptide 3H (APOBEC3H)

APOBEC3H encodes a member of the apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 family of proteins. The encoded protein is a cytidine deaminase that has antiretroviral activity by generating lethal hypermutations in viral genomes. Polymorphisms and alternative splicing in this gene influence its antiretroviral activity and are associated with increased resistence to human immunodeficiency virus type 1 infection in certain populations. Alternative splicing results in multiple transcript variants.In contrast, human APOBEC3H was poorly expressed at the protein level in human embryonic kidney cells and was ineffective at inhibiting retroviral replication. Poor expression of APOBEC3H was due to elevated degradation by proteasomes and not to reduced mRNA levels or protein translation.