{"product_id":"2940013247130","title":"The Biochemistry of Somatic Hypermutation","description":"Affinity maturation of the humoral response is mediated by somatic hypermutation of the immunoglobulin (Ig) genes and selection of higher-affinity B cell clones. Activation-induced cytidine deaminase (AID) is the first of a complex series of proteins that introduce these point mutations into variable regions of the Ig genes. AID deaminates deoxycytidine residues in single-stranded DNA to deoxyuridines, which are then processed by DNA replication, base excision repair (BER), or mismatch repair (MMR). In germinal center B cells, MMR, BER, and other factors are diverted from their normal roles in preserving genomic integrity to increase diversity within the Ig locus. Both AID and these components of an emerging error-prone mutasome are regulated on many levels by complex mechanisms that are only beginning to be elucidated.","brand":"Annual Reviews","offers":[{"title":"Default Title","offer_id":47152570695920,"sku":"2940013247130","price":9.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0737\/7593\/9824\/files\/2940013247130_p0.jpg?v=1763578754","url":"https:\/\/shop-qa.barnesandnoble.com\/products\/2940013247130","provider":"Barnes \u0026 Noble (DEV)","version":"1.0","type":"link"}