title: cDNA Library Screening Identifies Protein Interactors Potentially Involved in Non-Telomeric Roles of Arabidopsis Telomerase.
abstract: Telomerase-reverse transcriptase (TERT) plays an essential catalytic role in maintaining telomeres. However, in animal systems telomerase plays additional non-telomeric functional roles. We previously screened an Arabidopsis cDNA library for proteins that interact with the C-terminal extension (CTE) TERT domain and identified a nuclear-localized protein that contains an RNA recognition motif (RRM). This RRM-protein forms homodimers in both plants and yeast. Mutation of the gene encoding the RRM-protein had no detectable effect on plant growth and development, nor did it affect telomerase activity or telomere length in vivo, suggesting a non-telomeric role for TERT/RRM-protein complexes. The gene encoding the RRM-protein is highly expressed in leaf and reproductive tissues. We further screened an Arabidopsis cDNA library for proteins that interact with the RRM-protein and identified five interactors. These proteins are involved in numerous non-telomere-associated cellular activities. In plants, the RRM-protein, both alone and in a complex with its interactors, localizes to nuclear speckles. Transcriptional analyses in wild-type and rrm mutant plants, as well as transcriptional co-analyses, suggest that TERT, the RRM-protein, and the RRM-protein interactors may play important roles in non-telomeric cellular functions.
authors.affiliation: Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology and Faculty of Science, Masaryk University Brno, Czech Republic ; Institute of Biophysics - Academy of Sciences of the Czech Republic v.v.i. Brno, Czech Republic.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Dokládal
authors.affiliation: Institute of Experimental Botany - Academy of Sciences of the Czech Republic v.v.i. Prague, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Honys
authors.affiliation: Institute of Experimental Botany - Academy of Sciences of the Czech Republic v.v.i. Prague, Czech Republic.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Rana
authors.affiliation: Department of Biological Sciences, Purdue University, West Lafayette IN, USA.
authors.forename: Lan-Ying
authors.initials: LY
authors.lastname: Lee
authors.affiliation: Department of Biological Sciences, Purdue University, West Lafayette IN, USA.
authors.forename: Stanton B
authors.initials: SB
authors.lastname: Gelvin
authors.affiliation: Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology and Faculty of Science, Masaryk University Brno, Czech Republic ; Institute of Biophysics - Academy of Sciences of the Czech Republic v.v.i. Brno, Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Sýkorová
keywords: BiFC; MODIFIER OF snc1; metallothionein 2A; nuclear poly(A)-binding protein; oxidation-related zinc finger 2 protein; putative nuclear DNA-binding protein G2p; telobox; telomerase