title: The 5' untranslated region of the rbp1 mRNA is required for translation of its mRNA under low temperatures in the cyanobacterium Synechococcus elongatus.
abstract: The unicellular cyanobacterium Synechococcus elongatus has three RNA-binding protein (Rbp) genes, rbp1, rbp2 and rbp3. The rbp1 gene was upregulated by cold treatment while rbp2 and rbp3 expression decreased remarkably after exposure to cold temperatures. To investigate the mechanism underlying cold-induced rbp1 expression, a series of rbp1-luxAB transcriptional fusion constructs were expressed in S. elongatus PCC 7942 under cold conditions. The results showed that the region from -33 to -3 of the transcription initiation site contains an essential sequence for basal transcription of the rbp1 gene and that the 120-bp region (-34 to -153) does not contain critical cis-elements required for cold-shock induction. In contrast, mutational analysis carrying the 5'-untranslated region (UTR) of rbp1-luxAB translational fusions indicated that the 5'-UTR of rbp1 plays an important role in cold induction of the rbp1 gene product. Taken together, we conclude that the cold induction of rbp1 may be regulated at a posttranscriptional level rather than at the transcriptional level.
authors.affiliation: Center for Gene Research, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan.|Leica Microsystems K.K., Shirokane-takanawa Station Bldg., 1-27-6 Shirokane, Minato-ku, Tokyo, 108-0072, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Hayashi
authors.affiliation: Center for Gene Research, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan.
authors.forename: Chieko
authors.initials: C
authors.lastname: Sugita
authors.affiliation: Center for Gene Research, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan. sugita@gene.nagoya-u.ac.jp.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Sugita
mesh_terms: D020121:5' Untranslated Regions; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003080:Cold Temperature; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D046940:Synechococcus / Q000235:genetics* / Q000378:metabolism; D013696:Temperature
chemical_list: D020121:5' Untranslated Regions; D001426:Bacterial Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins
keywords: Cold shock; Cyanobacteria; Posttranscriptional regulation; RNA recognition motif; Synechococcus elongatus; mRNA stability