Mapping of interaction domains of putative telomere-binding proteins AtTRB1 and AtPOT1b from Arabidopsis thaliana.
We previously searched for interactions between plant telomere-binding proteins and found that AtTRB1, from the single-myb-histone (Smh) family, interacts with the Arabidopsis POT1-like-protein, AtPOT1b, involved in telomere capping. Here we identify domains responsible for that interaction. We also map domains in AtTRB1 responsible for interactions with other Smh-family-members. Our results show that the N-terminal OB-fold-domain of AtPOT1b mediates the interaction with AtTRB1. This domain is characteristic for POT1- proteins and is involved with binding the G-rich-strand of telomeric DNA. AtPOT1b also interacts with AtTRB2 and AtTRB3. The central histone-globular-domain of AtTRB1 is involved with binding to AtTRB2 and 3, as well as to AtPOT1b. AtTRB1-heterodimers with other Smh-family-members are more stable than AtTRB1-homodimers. Our results reveal interaction networks of plant telomeres.
Schrumpfová
Petra Procházková
PP
Department of Functional Genomics and Proteomics, Institute of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic.
Kuchar
Milan
M
Palecek
Jan
J
Fajkus
Jirí
J
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D019281:Dimerization; D006801:Humans; D008969:Molecular Sequence Data; D054730:Protein Interaction Domains and Motifs; D034501:Telomere-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D029681:Arabidopsis Proteins; D034501:Telomere-Binding Proteins; C529792:POT1b protein, Arabidopsis; C529793:At5g67580 protein, Arabidopsis; C529794:TRB3 protein, Arabidopsis; C428203:TRP1 telomere repeat-binding protein, Arabidopsis