Rabbit IgA heavy chain genes: cloning and in vitro expression.
Screening of recombinant cosmid and phage libraries with a rabbit C alpha cDNA probe has identified a total of seven C alpha genes organized into two clusters; one cluster contains four genes and the other cluster, three genes. Southern blot analysis of genomic DNA indicates that the rabbit genome contains a minimum of ten C alpha genes; at least three genes remain to be cloned. Four of the seven cloned C alpha genes have been tested for their ability to be expressed in vitro. Each gene was cloned 3' to a rearranged murine VDJ gene, and the chimeric gene was then transfected into J558L plasmacytoma cells. Stable transfectants were selected, and each transfectoma was shown to express a chimeric alpha-heavy chain. These chimeric alpha-heavy chains were of two sizes, 55 kd and 60 kd. Each of the four transfectomas secreted chimeric heavy chains in association with endogenous murine lambda light chains. All four C alpha genes tested were expressible, indicating that the rabbit may have multiple IgA subclasses or isotypes. This is in marked contrast to mouse and human which have only one and two subclasses of IgA, respectively.
Burnett
R C
RC
Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago.
Schneiderman
R D
RD
Knight
K L
KL
D000818:Animals; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D005784:Gene Amplification; D005786:Gene Expression Regulation; D005803:Genes, Immunoglobulin; D007127:Immunoglobulin Constant Regions / Q000235:genetics; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007137:Immunoglobulin alpha-Chains / Q000235:genetics*; D005810:Multigene Family; D011817:Rabbits
D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains; D007137:Immunoglobulin alpha-Chains; D004262:DNA Restriction Enzymes