Association of hepatic beta 2-adrenergic receptor gene transcript destabilization during postnatal development in the Sprague-Dawley rat with a M(r) 85,000 protein that binds selectively to the beta 2-adrenergic receptor mRNA 3'-untranslated region.
In the liver, transcript destabilization contributes to the decrease in steady-state levels of beta 2-adrenergic receptor mRNA that occurs during early postnatal development in the rat. From genomic DNA, polymerase chain reaction (PCR) was used to amplify a 718-basepair (bp) fragment of the beta 2-adrenergic receptor gene including the entire 3'-untranslated region. Results from SDS-gel electrophoresis and autoradiography demonstrated a M(r) 85,000 cellular factor present in postnatal day 60, but not fetal day 18 rat liver that was ultraviolet (UV) light-crosslinked to in vitro transcribed beta 2-adrenergic receptor RNA 3'-untranslated region. Unlabeled beta 2-adrenergic receptor RNA 3'-untranslated region, but not mouse beta-actin RNA, competed with labeled beta 2-adrenergic receptor RNA 3'-untranslated region for binding to the M(r) 85,000 protein. Cross-linking of the beta 2-adrenergic receptor RNA 3'-untranslated region to the M(r) 85,000 protein was inhibited by the ribohomopolymer poly(U), with poly(A), poly(C) and poly(G) having little or no effect. Thus, a M(r) 85,000 protein has been identified in adult male rat liver that may interact with U-rich sequences in the 3'-untranslated region of the beta 2-adrenergic receptor mRNA and may account for the decreased stability of hepatic beta 2-adrenergic receptor gene transcripts that occurs during development.
Baeyens
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Department of Biology, University of Arkansas at Little Rock 72204, USA.
Cornett
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D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000502:physiology*; D001483:Base Sequence; D001667:Binding, Competitive; D005333:Fetus / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D008970:Molecular Weight; D015345:Oligonucleotide Probes / Q000235:genetics; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011943:Receptors, Adrenergic, beta / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D014466:Ultraviolet Rays
D015345:Oligonucleotide Probes; D010446:Peptide Fragments; D012333:RNA, Messenger; D011943:Receptors, Adrenergic, beta