Several hundred papers in the past seven years have established two new mechanisms of immunity, both of which are dependent upon proteins that deaminate cytosines to uracils within singlestranded DNA. Activation-induced deaminase (AID) deaminates C -> U to implement the diversification of vertebrate antibody genes and mammalian APOBEC3 proteins, such as human APOBEC3F and APOBEC3G, deaminate C ...

Antiviral restriction factors are an integral part of the host innate immune system that protects cells from viral pathogens, such as human immunodeficiency virus (HIV). Studies of the interactions between restriction factors and HIV have greatly advanced our understanding of both the viral life cycle and basic cell biology, as well as provided new opportunities for therapeutic intervention of ...

HIV and HTLV have been recognized as important pathogens because of their association with lethal diseases in human: HIV causes Acquired Immunodeficiency Syndrome (AIDS) and HTLV is the etiological agent for adult T-cell leukemia. Considerable resources and efforts therefore have been directed at understanding the interaction between these human retroviruses and their host which may provide clu...