Identification of a Transcriptionally Forward α Gene and Two υ Genes within the Pigeon (Columba livia) IgH Gene Locus
| Autor: | Gengsheng Cao, Binyue Han, Tian Huang, Run Si, Haitang Han, Yaofeng Zhao, Xifeng Wang, Hao Chi |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
0301 basic medicine
Genetics Phylogenetic tree Immunology Locus (genetics) Biology Genome 03 medical and health sciences 030104 developmental biology 0302 clinical medicine Immunoglobulin class switching Phylogenetics Transcription (biology) Immunology and Allergy Gene conversion Gene 030215 immunology |
| Zdroj: | The Journal of Immunology. 200:3720-3728 |
| ISSN: | 1550-6606 0022-1767 |
| DOI: | 10.4049/jimmunol.1701768 |
| Popis: | Compared with mammals, the bird Ig genetic system relies on gene conversion to create an Ab repertoire, with inversion of the IgA-encoding gene and very few cases of Ig subclass diversification. Although gene conversion has been studied intensively, class-switch recombination, a mechanism by which the IgH C region is exchanged, has rarely been investigated in birds. In this study, based on the published genome of pigeon (Columba livia) and high-throughput transcriptome sequencing of immune-related tissues, we identified a transcriptionally forward α gene and found that the pigeon IgH gene locus is arranged as μ-α-υ1-υ2. In this article, we show that both DNA deletion and inversion may result from IgA and IgY class switching, and similar junction patterns were observed for both types of class-switch recombination. We also identified two subclasses of υ genes in pigeon, which share low sequence identity. Phylogenetic analysis suggests that divergence of the two pigeon υ genes occurred during the early stage of bird evolution. The data obtained in this study provide new insight into class-switch recombination and Ig gene evolution in birds. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|