Completing the TRB family: newly characterized members show ancient evolutionary origins and distinct localization, yet similar interactions
Year: 2023
Type: article
Abstract: Telomere repeat binding proteins (TRBs) belong to a family of proteins possessing a Myb-like domain which binds to telomeric repeats. Three members of this family (TRB1, TRB2, TRB3) from Arabidopsis thaliana have already been described as associated with terminal telomeric repeats (telomeres) or short interstitial telomeric repeats in gene promoters (telo-boxes). They are also known to interact with several protein complexes: telomerase, Polycomb repressive complex 2 (PRC2) E(z) subunits and the PEAT complex (PWOs-EPCRs-ARIDs-TRBs). Here we characterize two novel members of the TRB family (TRB4 and TRB5). Our wide phylogenetic analyses have shown that TRB proteins evolved in the plant kingdom after the transition to a terrestrial habitat in Streptophyta, and consequently TRBs diversified in seed plants. TRB4-5 share common TRB motifs while differing in several others and seem to have an earlier phylogenetic origin than TRB1-3. Their common Myb-like domains bind long arrays of telomeric repeats in vitro, and we have determined the minimal recognition motif of all TRBs as one telo-box. Our data indicate that despite the distinct localization patterns of TRB1-3 and TRB4-5 in situ, all members of TRB family mutually interact and also bind to telomerase/PRC2/PEAT complexes. Additionally, we have detected novel interactions between TRB4-5 and EMF2 and VRN2, which are Su(z)12 subunits of PRC2.
Source: Plant Molecular Biology
Institutions: Masaryk University, Central European Institute of Technology – Masaryk University, Czech Academy of Sciences, Czech Academy of Sciences, Institute of Experimental Botany, Institute of Plant Molecular Biology, Czech Academy of Sciences, Biology Centre, Freie Universität Berlin, Charles University
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,990
Awards: The role of Arabidopsis Lorelei-like GPI anchored proteins (LLGs) in pollen tube reception by the female gametophyte, National Infrastructure for Biological and Medical Imaging Czech-BioImaging, G1764578944, Biogenesis and evolution of telomerase in plants, G3017173846, Large Infrastructure CESNET, G3743894479, G4568151077, G4620337067, Gene expression in the male germline: regulatory factors and their responsive elements., G5840534618, G6393581779, G6713506817, G7058673349, G8068368242
OpenAlex ID: W4367307695