title: TOPLESS co-repressor interactions and their evolutionary conservation in plants.
abstract: Large-scale protein-protein interaction studies recently demonstrated that the Arabidopsis TPL/TPR family of transcriptional co-repressors is involved in a broad range of developmental processes. TPL/TPRs predominantly interact with transcription factors that contain repression domain (RD) sequences. Interestingly, RDs reported in the literature are quite diverse in sequence, yet TPL/TPRs interact with proteins containing all of the known motifs. These data lead us to conclude that the TPL/TPRs act as general repressors of gene transcription in plants. To investigate this further, we examined interactions between TPL/TPR proteins encoded by the moss Physcomitrella patens genome and components of the auxin signaling pathway. As in Arabidopsis, moss TPL proteins interact with AUX/IAA and ARF proteins, suggesting that they act in both forms of ARF-mediated transcriptional repression. These data suggest that the involvement of TPL in auxin signaling has been conserved across evolution, since mosses and angiosperms diverged approximately 450 million years ago.
authors.affiliation: Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
authors.forename: Barry
authors.initials: B
authors.lastname: Causier
authors.forename: James
authors.initials: J
authors.lastname: Lloyd
authors.forename: Laura
authors.initials: L
authors.lastname: Stevens
authors.forename: Brendan
authors.initials: B
authors.lastname: Davies
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D056970:Co-Repressor Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D019143:Evolution, Molecular; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D018745:Genome, Plant / Q000235:genetics; D010802:Phylogeny; D011485:Protein Binding / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D056970:Co-Repressor Proteins; C511291:At1g15750 protein, Arabidopsis