title: AtHESPERIN: a novel regulator of circadian rhythms with poly(A)-degrading activity in plants.
abstract: We report the identification and characterization of a novel gene, AtHesperin (AtHESP) that codes for a deadenylase in Arabidopsis thaliana. The gene is under circadian clock-gene regulation and has similarity to the mammalian Nocturnin. AtHESP can efficiently degrade poly(A) substrates exhibiting allosteric kinetics. Size exclusion chromatography and native electrophoresis coupled with kinetic analysis support that the native enzyme is oligomeric with at least 3 binding sites. Knockdown and overexpression of AtHESP in plant lines affects the expression and rhythmicity of the clock core oscillator genes TOC1 and CCA1. This study demonstrates an evolutionary conserved poly(A)-degrading activity in plants and suggests deadenylation as a mechanism involved in the regulation of the circadian clock. A role of AtHESP in stress response in plants is also depicted.
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Costas
authors.initials: C
authors.lastname: Delis
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Afrodite
authors.initials: A
authors.lastname: Krokida
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Tomatsidou
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Daniela
authors.initials: D
authors.lastname: Tsikou
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Rafailia A A
authors.initials: RA
authors.lastname: Beta
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Tsioumpekou
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Julietta
authors.initials: J
authors.lastname: Moustaka
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Stravodimos
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Demetres D
authors.initials: DD
authors.lastname: Leonidas
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Nikolaos A A
authors.initials: NA
authors.lastname: Balatsos
authors.affiliation: a Department of Biochemistry and Biotechnology , University of Thessaly , Larissa , 412 21 , Greece.
authors.forename: Kalliope K
authors.initials: KK
authors.lastname: Papadopoulou
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D002940:Circadian Rhythm; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018506:Gene Expression Regulation, Plant; D018384:Oxidative Stress; D011061:Poly A / Q000378:metabolism*; D055503:Protein Multimerization; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; C114425:CCA1 protein, Arabidopsis; C411822:TOC1 protein, Arabidopsis; D014157:Transcription Factors; D011061:Poly A
keywords: Allosteric; Arabidopsis; RNA stability; circadian; deadenylation; nocturnin