Molecular cloning of the coding sequence of an interleukin-2 receptor alpha subunit cDNA in murine brain.
Interleukin-2 (IL-2) has various trophic and neuromodulatory actions in the mammalian central nervous system (CNS). The interleukin-2 receptor alpha (IL-2R alpha) is an accessory subunit of the IL-2 receptor heterotrimer complex which is essential for 'high' affinity IL-2 binding. Although an IL-2R alpha (or IL-2R alpha-like) epitope has been localized in brain by immunohistocytochemistry, it was unknown whether the IL-2R alpha subunit expressed in brain was derived from the same or a different gene than the lymphocyte IL-2R alpha. Therefore, in the present study, the cDNA comprising the full length coding region was cloned and sequenced from saline-perfused forebrain. The brain IL-2R alpha cDNA was found to be 100% homologous with the corresponding lymphocyte IL-2R alpha cDNA sequence. IL-2R alpha mRNA was expressed at very low levels in saline-perfused forebrain of non-challenged BALB/c mice as well as in saline-perfused forebrain from severe combined immunodeficiency (SCID) mice. The present data, demonstrating IL-2R alpha gene expression in both well-perfused normal and SCID mouse forebrain from which no CD3 gamma gene expression was detected by PCR, provides evidence that the IL-2R alpha clones isolated are from resident brain cells and not from blood lymphocytes (e.g. T lymphocytes). Thus, these findings demonstrate that the protein coding sequence of the mouse brain IL-2R alpha is derived from the same gene coding sequence as the lymphocyte IL-2R alpha, and indicate that previously reported differences in the size of their respective mRNA transcripts appear to be due to differences in untranslated regions.
Petitto
J M
JM
Department of Psychiatry, University of Florida College of Medicine, Gainesville 32610-0256, USA.
Huang
Z
Z
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016548:Prosencephalon / Q000737:chemistry*; D012333:RNA, Messenger / Q000032:analysis; D015375:Receptors, Interleukin-2 / Q000235:genetics*
D018076:DNA, Complementary; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2