edoc

Origin of immunoglobulin isotype switching

Zhu, C. and Lee, V. and Finn, A. and Senger, K. and Du Pasquier, L. and Hsu, E.. (2012) Origin of immunoglobulin isotype switching. Current Biology, 22 (10). pp. 872-880.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/48530/

Downloads: Statistics Overview

Abstract

Background
From humans to frogs, immunoglobulin class switching introduces different effector functions to antibodies through an intrachromosomal DNA recombination process at the heavy-chain locus. Although there are two conventional antibody classes (IgM, IgW) in sharks, their heavy chains are encoded by 20 to >100 miniloci. These representatives of the earliest jawed vertebrates possess a primordial immunoglobulin gene organization where each gene cluster is autonomous and contains a few rearranging gene segments (VH-D1-D2-JH) with one constant region, μ or ω.
Results
V(D)J rearrangement always takes place within the μ cluster, but here we show that the VDJ can be expressed with constant regions from different clusters, although IgH genes are spatially distant, at >120 kb. Moreover, reciprocal exchanges take place between Igω and Igμ genes. Switching is augmented with deliberate immunization and is concomitant with somatic hypermutation activity. Because switching occurs independently of the partners' linkage position, some events involve transchromosomal recombination. The switch sites consist of direct joins between two genes in the 3′ intron flanking JH.
Conclusions
Our data are consistent with a mechanism of cutting or joining of distal DNA lesions initiated by activation-induced cytidine deaminase (AID), in the absence of mammalian-type switch regions. We suggest that, in shark, with its many autonomous IgH targeted by programmed DNA breakage, factors predisposing broken DNA ends to translocate configured the earliest version of class switch recombination.
Faculties and Departments:05 Faculty of Science > Departement Umweltwissenschaften > Zoologie > Evolution des Immunsystems (Du Pasquier)
UniBasel Contributors:Du Pasquier, Louis
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:Cell Press
ISSN:0960-9822
e-ISSN:1879-0445
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:19 Jan 2018 08:19
Deposited On:19 Jan 2018 08:19

Repository Staff Only: item control page