Multiple components in restriction enzyme digests of mammalian (insectivore), avian and reptilian genomic DNA hybridize with murine immunoglobulin VH probes

Abstract

High molecular weight genomic DNAs isolated from an insectivore, Tupaia and a representative reptilian, Caiman and avian, Gallus were digested with restriction endonucleases transferred to nitrocellulose and hybridized with nick-translated probes of murine VH genes. The derivations of the probes designated S107V (1) and pl07V (2,3) have been described previously. Under conditions of reduced stringency, multiple hybridizing components were observed with Tupaia and Caiman only μl07V exhibited significant hybridization with the separated fragments of Gallus DNA. The nick-trans lated S1O7V probe was digested with Fnu4H1 and subinserts corresponding to the 5' and 3' regions both detected multiple hybridizing components in Tupaia and Caiman DNA. A 5' probe lacking the leader sequence identified the same components as the intact 5' probe, suggesting that VH coding regions were being detected. The results indicate that species as phylogenetically distant as the reptilians may possess multiple genetic components which exhibit significant homology with murine immunoglobulin VH regions. © 1982 IRL Press Limited.