Multiple mRNA isoforms of the transcription activator protein CREB: generation by alternative splicing and specific expression in primary spermatocytes.
We have characterized cDNA clones representing mouse CREB (cyclic AMP responsive element binding protein) mRNA isoforms. These include CREB delta and CREB alpha, of which the rat and human homologues have been previously identified. Both encode proteins with CRE-binding activity and identical transactivation potential. The additional CREB mRNA isoforms potentially encode CREB related proteins. From the structural organization of the mouse CREB gene we conclude that the multiple transcripts are generated by alternative splicing. Furthermore we show that specific CREB mRNA isoforms are expressed at a high level in the adult testis. Expression of these isoforms is induced after commencement of spermatogenesis. In situ hybridization suggests that this expression occurs predominantly in the primary spermatocytes. Comparison of the CREB gene with the recently isolated CREM (cAMP responsive element modulator) cDNAs illustrates that the two genes have arisen by gene duplication and have diverged to encode transcriptional activators and repressors of the cAMP signal transduction pathway.
Ruppert
S
S
German Cancer Research Center, Institute of Cell and Tumor Biology, Heidelberg.
Cole
T J
TJ
Boshart
M
M
Schmid
E
E
Schütz
G
G
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D017362:Cyclic AMP Response Element-Binding Protein; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005091:Exons; D015723:Gene Library; D008099:Liver / Q000502:physiology; D008297:Male; D008546:Melanoma, Experimental; D051379:Mice; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D013090:Spermatocytes / Q000166:cytology / Q000502:physiology*; D013724:Teratoma; D014157:Transcription Factors / Q000235:genetics; D014162:Transfection
D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014157:Transcription Factors; D004247:DNA