title: Sequencing of Sylvilagus VDJ genes reveals a new VHa allelic lineage and shows that ancient VH lineages were retained differently in leporids.
abstract: Antigen recognition by immunoglobulins depends upon initial rearrangements of heavy chain V, D, and J genes. In leporids, a unique system exists for the VH genes usage that exhibit highly divergent lineages: the VHa allotypes, the Lepus sL lineage and the VHn genes. For the European rabbit (Oryctolagus cuniculus), four VHa lineages have been described, the a1, a2, a3 and a4. For hares (Lepus sp.), one VHa lineage was described, the a2L, as well as a more ancient sL lineage. Both genera use the VHn genes in a low frequency of their VDJ rearrangements. To address the hypothesis that the VH specificities could be associated with different environments, we sequenced VDJ genes from a third leporid genus, Sylvilagus. We found a fifth and equally divergent VHa lineage, the a5, and an ancient lineage, the sS, related to the hares' sL, but failed to obtain VHn genes. These results show that the studied leporids employ different VH lineages in the generation of the antibody repertoire, suggesting that the leporid VH genes are subject to strong selective pressure likely imposed by specific pathogens.
authors.affiliation: CIBIO Centro de Investigação em Biodiversidade e Recursos Genéticos, InBio Laboratório Associado, Universidade do Porto, Campus Agrário de Vairão, 4485-661, Vairão, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Pinheiro
authors.forename: José
authors.initials: J
authors.lastname: Melo-Ferreira
authors.forename: Joana
authors.initials: J
authors.lastname: Abrantes
authors.forename: Nicola
authors.initials: N
authors.lastname: Martinelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Lavazza
authors.forename: Paulo C
authors.initials: PC
authors.lastname: Alves
authors.forename: Christian
authors.initials: C
authors.lastname: Gortázar
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: Esteves
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D019143:Evolution, Molecular; D015870:Gene Expression; D008040:Genetic Linkage; D007135:Immunoglobulin Variable Region / Q000737:chemistry / Q000235:genetics*; D007793:Lagomorpha / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D011817:Rabbits; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D050441:VDJ Exons / Q000235:genetics*
chemical_list: D007135:Immunoglobulin Variable Region