title: Developmental regulation of RNA transcript destabilization by A + U-rich elements is AUF1-dependent.
abstract: The developmental immaturity of neonatal phagocytic function is associated with decreased accumulation and half-life (t((1)/(2))) of granulocyte/macrophage colony-stimulating factor (GM-CSF) mRNA in mononuclear cells (MNC) from the neonatal umbilical cord compared with adult peripheral blood. The in vivo t((1)/(2)) of GM-CSF mRNA is 3-fold shorter in neonatal (30 min) than in adult (100 min) MNC. Turnover of mRNA containing a 3'-untranslated region (3'-UTR) A + U-rich element (ARE), which regulates GM-CSF mRNA stability, is accelerated in vitro by protein fractions enriched for AUF1, an ARE-specific binding factor. The data reported here demonstrate that the ARE significantly accelerates in vitro decay of the GM-CSF 3'-UTR in the presence of either neonatal or adult MNC protein. Decay intermediates of the GM-CSF 3'-UTR are generated that are truncated at either end of the ARE. Furthermore, the t((1)/(2)) of the ARE-containing 3'-UTR is 4-fold shorter in the presence of neonatal (19 min) than adult (79 min) MNC protein, reconstituting developmental regulation in a cell-free system. Finally, accelerated ARE-dependent decay of the GM-CSF 3'-UTR in vitro by neonatal MNC protein is significantly attenuated by immunodepletion of AUF1, providing new evidence that this accelerated turnover is ARE- and AUF1-dependent.
authors.affiliation: Hematology Research Laboratory, Children's Hospital of Orange County, Orange, California 92868, USA. jsbuzby@hotmail.com
authors.forename: J S
authors.initials: JS
authors.lastname: Buzby
authors.forename: G
authors.initials: G
authors.lastname: Brewer
authors.forename: D J
authors.initials: DJ
authors.lastname: Nugent
mesh_terms: D020413:3' Untranslated Regions / Q000378:metabolism; D000328:Adult; D002478:Cells, Cultured; D018507:Gene Expression Regulation, Developmental; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000378:metabolism; D006207:Half-Life; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D006801:Humans; D007231:Infant, Newborn; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid; D014158:Transcription, Genetic
chemical_list: D020413:3' Untranslated Regions; C000630986:HNRNPD protein, human; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D012313:RNA; D016178:Granulocyte-Macrophage Colony-Stimulating Factor