title: A short RNA stem-loop is necessary and sufficient for repression of gene expression during early logarithmic phase in trypanosomes.
abstract: We have compared the transcriptomes of cultured procyclic Trypanosoma brucei cells in early and late logarithmic phases and found that ∼200 mRNAs were differentially regulated. In late log phase cells, the most upregulated mRNA encoded the nucleobase transporter NT8. The 3' untranslated region (UTR) of NT8 contains a short stem-loop cis-element that is necessary for the regulation of NT8 expression in response to external purine levels. When placed in the 3'-UTR of an unregulated transcript, the cis-element is sufficient to confer regulation in response to purines. To our knowledge, this is the first example of a discrete RNA element that can autonomously regulate gene expression in trypanosomes in response to an external factor and reveals an unprecedented purine-dependent signaling pathway that controls gene expression in eukaryotes.
authors.affiliation: Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento, s/n, 18016 Armilla, Granada, Spain.
authors.forename: Sandra M
authors.initials: SM
authors.lastname: Fernández-Moya
authors.affiliation: Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Carrington
authors.affiliation: Instituto de Parasitología y Biomedicina 'López-Neyra', IPBLN-CSIC, Parque Tecnológico de Ciencias de la Salud, Avda. del Conocimiento, s/n, 18016 Armilla, Granada, Spain aestevez@ipb.csic.es.
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Estévez
mesh_terms: D020413:3' Untranslated Regions; D005786:Gene Expression Regulation; D009690:Nucleic Acid Conformation; D033702:Nucleobase Transport Proteins / Q000235:genetics* / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics* / Q000378:metabolism; D011687:Purines / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D038621:Regulatory Sequences, Ribonucleic Acid; D059467:Transcriptome; D014346:Trypanosoma brucei brucei / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D033702:Nucleobase Transport Proteins; D015800:Protozoan Proteins; D011687:Purines; D012333:RNA, Messenger; D038621:Regulatory Sequences, Ribonucleic Acid