title: Structure-function relationships during transgenic telomerase expression in Arabidopsis.
abstract: Although telomerase (EC 2.7.7.49) is important for genome stability and totipotency of plant cells, the principles of its regulation are not well understood. Therefore, we studied subcellular localization and function of the full-length and truncated variants of the catalytic subunit of Arabidopsis thaliana telomerase, AtTERT, in planta. Our results show that multiple sites in AtTERT may serve as nuclear localization signals, as all the studied individual domains of the AtTERT were targeted to the nucleus and/or the nucleolus. Although the introduced genomic or cDNA AtTERT transgenes display expression at transcript and protein levels, they are not able to fully complement the lack of telomerase functions in tert -/- mutants. The failure to reconstitute telomerase function in planta suggests a more complex telomerase regulation in plant cells than would be expected based on results of similar experiments in mammalian model systems.
authors.affiliation: Faculty of Science and Central European Institute of Technology, Masaryk University, CZ-61137, Brno, Czech Republic.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Zachová
authors.forename: Miloslava
authors.initials: M
authors.lastname: Fojtová
authors.forename: Martina
authors.initials: M
authors.lastname: Dvořáčková
authors.forename: Iva
authors.initials: I
authors.lastname: Mozgová
authors.forename: Inna
authors.initials: I
authors.lastname: Lermontova
authors.forename: Vratislav
authors.initials: V
authors.lastname: Peška
authors.forename: Ingo
authors.initials: I
authors.lastname: Schubert
authors.forename: Jiří
authors.initials: J
authors.lastname: Fajkus
authors.forename: Eva
authors.initials: E
authors.lastname: Sýkorová
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D020134:Catalytic Domain / Q000235:genetics; D002466:Cell Nucleolus / Q000201:enzymology / Q000235:genetics; D002467:Cell Nucleus / Q000201:enzymology / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D019913:Nuclear Localization Signals / Q000235:genetics; D018515:Plant Leaves / Q000235:genetics; D030821:Plants, Genetically Modified; D014176:Protein Biosynthesis; D017434:Protein Structure, Tertiary; D012326:RNA Splicing; D013329:Structure-Activity Relationship; D019098:Telomerase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism*; D014026:Nicotiana / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D019913:Nuclear Localization Signals; D019098:Telomerase