Submitted to: Avian Immunology Group Meeting
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2004
Publication Date: September 1, 2004
Citation: Min, W., Lillehoj, H.S. 2004. Molecular and functional characterization of an alternatively spliced transcript isoform of the common cytokine receptor gamma chain. Avian Immunology Group Meeting, p. 83.
The common cytokine receptor gamma (gamma c) chain is a shared component of the receptors for IL-2, -4, -7, -9, -15, and -21, and is a member of the cytokine receptor superfamily displaying a characteristic spacing of four conserved cysteine residues and a WSXWS motif. The gammac chain is expressed as a transmembrane glycoprotein on CD4+ and CD8+ T cells, B cells, NK cells, monocytes/macrophages, neutrophils, and granulocytes where it forms heterodimeric or heterotrimeric complexes with specific interleukin receptors thereby augmenting ligand affinity, receptor internalization, and signal transduction. In this study, we discovered that, unlike mammals, chickens possess two different gamma gamma c gene transcripts, chgammac-a and chgammac-b. Sequence comparisons between the cDNAs and a gammac genomic clone isolated by PCR revealed that chgammac-b contained an in-frame 78 bp insertion between Gly-222 and Val-223 of the chgammac-a sequence. This insertion most likely resulted from alternative mRNA splicing such that the 5th intron was not removed from the chgammac-b transcript. Furthermore, while chgammac-a and chgammac-b transcripts were expressed equally in the spleen, thymus, bursa, and cecal tonsils, they were differentially expressed during the time course of Con A stimulation of splenic T lymphocytes.