Multiple transcription start sites and 5' alternate splicing of murine IL-3 receptor beta-chain transcripts.
The murine interleukin-3 receptor beta-chain genes, IL-3R beta IL-3 and IL-3R beta c, encode the signal transducing chains of the high affinity receptors for IL-3 and IL-3, GM-CSF and IL-5 respectively. Little is known about the regulation of their expression. To enable the study of the promotors of IL-3R beta IL-3 and IL-3R beta c, we have characterized their respective 5' untranslated regions using a modified 5' RACE protocol. Four classes of alternatively spliced transcripts were isolated that initiate in a 400 nt region upstream from a previously reported start site(1). The initially reported partial IL-3R beta IL-3 clone belongs to the first class of transcripts(2). The second class starts in the middle of an intron as defined by the first class. The 3rd and 4th class establish 2 novel splice donor sites. These results were confirmed by RNAse-protection assay. The complex organization as evident from our data establishes an experimental framework for future experiments aimed at the study of the promoters for the murine IL-3R beta genes.
Norga
K
K
Division of Pediatric Oncology and Hematology, Dana-Farber Cancer Institute, Boston, MA 02115.
Pless
M
M
Stanulla
M
M
TePas
E C
EC
Mathey-Prevot
B
B
D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D017931:DNA Primers; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism; D016185:Receptors, Interleukin-3 / Q000235:genetics*; D012260:Ribonucleases / Q000378:metabolism; D014158:Transcription, Genetic
D017931:DNA Primers; D012333:RNA, Messenger; D016185:Receptors, Interleukin-3; D012260:Ribonucleases