title: Interleukin-5 does not influence differential transcription of transmembrane and soluble isoforms of IL-5R alpha in vivo.
abstract: Interleukin-5 (IL-5) promotes signal transduction and expansion of eosinophil colonies in bone marrow via interactions with its heterodimeric receptor (IL-5R). Two variants encoding soluble forms of the alpha subunit (sIL-5R alpha) have been described, although the signals promoting and/or limiting differential transcription remain to be clarified.
  
  
  OBJECTIVE
  Our intent was to explore the role of IL-5 in regulating differential transcription of these splice variants in vivo.
  
  
  METHODS
  We have designed a quantitative reverse transcriptase-polymerase chain reaction assay to detect transcripts encoding the transmembrane, soluble 1 and 2 forms of IL-5R alpha in two strains of wild-type (BALB/c and C57BL/6) and corresponding IL-5 gene-deleted mice. Wild-type mice respond to S. mansoni infection with a gradual increase in serum IL-5 and eosinophilia, which is not observed in IL-5 gene-deleted mice.
  
  
  CONCLUSIONS
  We find that IL-5 is not necessary for differential splicing to occur in vivo, as all three forms of the IL-5R alpha are detected in both strains of IL-5 gene-deleted mice, with ratios of transcript expression (transmembrane : soluble 1 : soluble 2) that were indistinguishable from their wild-type counterparts. Differential splicing does vary markedly between strains, potentially because of local effects of strain-specific polymorphisms.
authors.affiliation: Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1883, USA.
authors.forename: Jonas
authors.initials: J
authors.lastname: Byström
authors.forename: Kimberly D
authors.initials: KD
authors.lastname: Dyer
authors.forename: Suk See
authors.initials: SS
authors.lastname: Ting-De Ravin
authors.forename: Nora
authors.initials: N
authors.lastname: Naumann
authors.forename: David A
authors.initials: DA
authors.lastname: Stephany
authors.forename: Paul S
authors.initials: PS
authors.lastname: Foster
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Wynn
authors.forename: Helene F
authors.initials: HF
authors.lastname: Rosenberg
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D001853:Bone Marrow / Q000473:pathology; D018076:DNA, Complementary / Q000235:genetics; D004804:Eosinophils / Q000473:pathology; D005091:Exons; D015848:Interleukin-5 / Q000097:blood / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D018123:Receptors, Interleukin / Q000096:biosynthesis* / Q000235:genetics*; D053649:Receptors, Interleukin-5; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012555:Schistosomiasis mansoni / Q000235:genetics / Q000276:immunology / Q000473:pathology; D012995:Solubility; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D015848:Interleukin-5; D020033:Protein Isoforms; D018123:Receptors, Interleukin; D053649:Receptors, Interleukin-5