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Persons with serious mental illnesses experience high rates of medical comorbidity, especially diabetes. This study examined initial implementation feasibility, acceptability, and appropriateness of a new 6-month Multicomponent Intervention for Diabetes risk reduction in Adults with Serious mental illnesses (MIDAS) among persons in residential care facilities (RCFs). We conducted a mixed-methods study using four types of quantitative and qualitative data sources (administrative data; structured facility-level observations; resident assessments including blood-based biomarkers, 24-h dietary recalls, and self-report physical activity; and focus groups/interviews with staff and participants), to assess evidence of and factors affecting intervention feasibility, acceptability, and appropriateness. It was feasible to provide a high percentage of MIDAS class sessions (mean 50 of 52 intended sessions delivered) and make nutrition-related RCF changes (substitutions for healthier food items and reduced portion sizes). Class attendance rates and positive feedback from residents and staff provided evidence of MIDAS acceptability and appropriateness for addressing identified health needs. The residents who attended ≥ 85% of the sessions had greater improvement in several desired outcomes compared to others. Implementing a fully integrated MIDAS model with more extensive changes to facilities and more fundamental health changes among residents was more challenging. While the study found evidence to support feasibility, acceptability, and appropriateness of individual MIDAS components, some challenges for full implementation and success in obtaining immediate health benefits were also apparent. The study results highlight the need for improving health among RCF populations and will inform MIDAS adaptations designed to improve intervention fit and effectiveness outcomes. [ABSTRACT FROM AUTHOR]

Summary: The role of the floral homeotic gene AGAMOUS (AG) and its close homologues in development of anemophilous, unisexual catkins has not previously been studied.We transformed two RNA interference (RNAi) constructs, PTG and its matrix‐attachment‐region flanked version MPG, into the early‐flowering female poplar clone 6K10 (Populus alba) to suppress the expression of its two duplicate AG orthologues.By early 2018, six out of 22 flowering PTG events and 11 out of 12 flowering MPG events showed modified floral phenotypes in a field trial in Oregon, USA. Flowers in catkins from modified events had 'carpel‐inside‐carpel' phenotypes. Complete disruption of seed production was observed in seven events, and sterile anther‐like organs in 10 events. Events with strong co‐suppression of both the two AG and two SEEDSTICK (STK) paralogues lacked both seeds and associated seed hairs. Alterations in all of the modified floral phenotypes were stable over 4 yr of study. Trees from floral‐modified events did not differ significantly (P < 0.05) from nonmodified transgenic or nontransgenic controls in biomass growth or leaf morphology.AG and STK genes show strong conservation of gene function during poplar catkin development and are promising targets for genetic containment of exotic or genetically engineered trees. [ABSTRACT FROM AUTHOR]

A tree shoot includes multiple developmental gradients that reflect the relationships of the shoot apical meristem, the cambial meristem and the tissues and organs they produce. The adaptation of trees to temperate and boreal climates depends on the ability of these two meristems to appropriately respond to environmental signals that are markers of seasonal changes. The aim of this review is to present a more holistic view of the tree shoot, including the developmental changes associated with seasonally regulated growth transitions. We consider the role of long-distance communication in coordinating leaf development, the transition to secondary growth and meristem activity. Using Populus as the model, we discuss the roles of signalling mediated by hormones, sugar and FLOWERING LOCUS T2 (FT2) in coordinating tree shoot developmental processes. [ABSTRACT FROM AUTHOR]

Vegetative and reproductive phase change and phenology are economically and ecologically important traits. Trees typically require several years of growth before flowering and, once mature, seasonal control of the transition to flowering and flower development is necessary to maintain vegetative meristems and for reproductive success. Members of two related gene subfamilies, FLOWERING LOCUST (FT) and TERMINAL FLOWER1 (TFL1)/ CENTRORADIALIS (CEN)/ BROTHER OF FT AND TFL1 (BFT), have antagonistic roles in flowering in diverse species and roles in vegetative phenology in trees, but many details of their functions in trees have yet to be resolved. Here, we used CRISPR/Cas9 to generate single and double mutants involving the five Populus FT and TFL1/CEN/BFT genes. The ft1 mutants exhibited wild-type-like phenotypes in long days and short days, but after chilling, to release dormancy, they showed delayed bud flush and GA3 could compensate for the ft1 mutation. After rooting and generating some phytomers in tissue culture, both cen1 and cen1ft1 mutants produced terminal as well as axillary flowers, indicating that the cen1 flowering phenotype is independent of FT1. The CEN1 showed distinct circannual expression patterns in vegetative and reproductive tissues and comparison with the expression patterns of FT1 and FT2 suggests that the relative levels of CEN1 compared with FT1 and FT2 regulate multiple phases of vegetative and reproductive seasonal development. [ABSTRACT FROM AUTHOR]

We investigated the ability of RNA interference (RNAi) directed against two co-orthologs of AGAMOUS (AG) from Malus domestica (domestic apple, MdAG) to reduce the risks of invasiveness and provide genetic containment of transgenes, while also promoting the attractiveness of flowers for ornamental usage. Suppression of two MdAG-like genes, MdMADS15 and MdMADS22, led to the production of trees with highly showy, polypetalous flowers. These “double-flowers” had strongly reduced expression of both MdAG-like genes. Members of the two other clades within in the MdAG subfamily showed mild to moderate differences in gene expression, or were unchanged, with the level of suppression approximately proportional to the level of sequence identity between the gene analyzed and the RNAi fragment. The double-flowers also exhibited reduced male and female fertility, had few viable pollen grains, a decreased number of stigmas, and produced few viable seeds after cross-pollination. Despite these floral alterations, RNAi-AG trees with double-flowers set full-sized fruit. Suppression or mutation of apple AG-like genes appears to be a promising method for combining genetic containment with improved floral attractiveness. [ABSTRACT FROM AUTHOR]

Summary: DIVARICATA AND RADIALIS INTERACTING FACTOR (DRIF) from snapdragon (Antirrhinum majus) is a MYB/SANT protein that interacts with related MYB/SANT proteins, RADIALIS and DIVARICATA, through its N‐terminal MYB/SANT domain. In addition to the MYB/SANT domain, DRIF contains a C‐terminal domain of unknown function (DUF3755). Here we describe novel protein–protein interactions involving a poplar (Populus trichocarpa) homolog of DRIF, PtrDRIF1. In addition to interacting with poplar homologs of RADIALIS (PtrRAD1) and DIVARICATA (PtrDIV4), PtrDRIF1 interacted with members of other families within the homeodomain‐like superfamily, including PtrWOX13c, a WUSCHEL‐RELATED HOMEOBOX protein, and PtrKNAT7, a KNOTTED1‐LIKE HOMEOBOX protein. PtrRAD1 and PtrDIV4 interacted with the MYB/SANT‐containing N‐terminal portion of PtrDRIF1, whereas DUF3755 was both necessary and sufficient for interactions with PtrWOX13c and PtrKNAT7. Of the two MYB/SANT domains present in PtrDIV4, only the N‐terminal MYB/SANT domain interacted with PtrDRIF1. GFP‐PtrDRIF1 expressed alone or with PtrRAD1 localized to the cytoplasm, whereas co‐expression of GFP‐PtrDRIF1 with PtrDIV4, PtrWOX13c or PtrKNAT7 resulted in nuclear localization of GFP‐PtrDRIF1. Modified yeast two‐hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) experiments using PtrDRIF1 as a bridge protein revealed that PtrDRIF1 simultaneously interacted with PtrRAD1 and PtrWOX13c, but could not form a heterotrimeric complex when PtrDIV4 was substituted for PtrRAD1. Moreover, a Y2H competition assay indicated that PtrKNAT7 inhibits the interaction between PtrRAD1 and PtrDRIF1. The discovery of an additional protein–protein interaction domain in DRIF proteins, DUF3755, and its ability to form heterodimers and heterotrimers involving MYB/SANT and wood‐associated homeodomain proteins, implicates DRIF proteins as mediators of a broader array of processes than previously reported. [ABSTRACT FROM AUTHOR]

Cellular processes, such as signal transduction and cell wall deposition, are organized by macromolecule interactions. Experimentally determined protein-protein interactions (PPIs) and protein-DNA interactions (PDIs) relevant to woody plant development are sparse. To begin to develop a Populus trichocarpa Torr. & A. Gray wood interactome, we applied the yeast-two-hybrid (Y2H) assay in different ways to enable the discovery of novel PPIs and connected networks. We first cloned open reading frames (ORFs) for 361 genes markedly upregulated in secondary xylem compared with secondary phloem and performed a binary Y2H screen with these proteins. By screening a xylem cDNA library for interactors of a subset of these proteins and then recapitulating the process by using a subset of the interactors as baits, we ultimately identified 165 PPIs involving 162 different ORFs. Thirty-eight transcription factors (TFs) included in our collection of P. trichocarpa wood ORFs were used in a Y1H screen for binding to promoter regions of three genes involved in lignin biosynthesis resulting in 40 PDIs involving 20 different TFs. The network incorporating both the PPIs and PDIs included 14 connected subnetworks, with the largest having 132 members. Protein-protein interactions and PDIs validated previous reports and also identified new candidate wood formation proteins and modules through their interactions with proteins and promoters known to be involved in secondary cell wall synthesis. Selected examples are discussed including a PPI between Mps one binder (MOB1) and a mitogen-activated protein kinase kinase kinase kinase (M4K) that was further characterized by assays confirming the PPI as well as its effect on subcellular localization. Mapping of published transcriptomic data showing developmentally detailed expression patterns across a secondary stem onto the network supported that the PPIs and PDIs are relevant to wood formation, and also illustrated that wood-associated interactions involve gene products that are not upregulated in secondary xylem. [ABSTRACT FROM AUTHOR]

The Arabidopsis thaliana gene XYLEM NAC DOMAIN1 ( XND1) is upregulated in xylem tracheary elements. Yet overexpression of XND1 blocks differentiation of tracheary elements. The molecular mechanism of XND1 action was investigated., Phylogenetic and motif analyses indicated that XND1 and its homologs are present only in angiosperms and possess a highly conserved C-terminal region containing linear motifs (CKII-acidic, LXCXE, E2FTD-like and LXCXE-mimic) predicted to interact with the cell cycle and differentiation regulator RETINOBLASTOMA-RELATED (RBR). Protein-protein interaction and functional analyses of XND1 deletion mutants were used to test the importance of RBR-interaction motifs., Deletion of either the LXCXE or the LXCXE-mimic motif reduced both the XND1-RBR interaction and XND1 efficacy as a repressor of differentiation, with loss of the LXCXE motif having the strongest negative impacts. The function of the XND1 C-terminal domain could be partially replaced by RBR fused to the N-terminal domain of XND1. XND1 also transactivated gene expression in yeast and plants., The properties of XND1, a transactivator that depends on multiple linear RBR-interaction motifs to inhibit differentiation, have not previously been described for a plant protein. XND1 harbors an apparently angiosperm-specific combination of interaction motifs potentially linking the general differentiation regulator RBR with a xylem-specific pathway for inhibition of differentiation. [ABSTRACT FROM AUTHOR]

T-DNA insertion mutants play a crucial role in elucidating Arabidopsis gene function. In some cases, two or more T-DNA mutants are combined to study genetic interactions between homologous genes or genes hypothesized to act in the same pathway. We studied the significance of protein–protein interactions between CSN5A and ROP11 by crossing three independent rop11 T-DNA insertion mutants with csn5a -2, a partial loss-of-function intronic T-DNA insertion mutant. The csn5a-2 single mutant is severely stunted, but double rop11 csn5a-2 mutants were rescued and exhibited increased CSN5A transcript and protein levels. The rescued phenotype was maintained in non-Mendelian fashion when the csn5a-2 single mutant was re-isolated from the rop11-1 csn5a-2 double mutant, and was sensitive to two inhibitors of DNA methylation. Loss of kanamycin resistance was also observed in re-isolated csn5a-2 . These findings indicate that the rescue of csn5a-2 resulted from a trans T-DNA-mediated epigenetic effect on the csn5a-2 intronic T-DNA, similar to recent reports involving the intronic T-DNA mutants ag-TD , ben1-1 , and cob-6 . Thus the work reported here provides further support for the recommendation that mutants created through novel combinations of T-DNA alleles should be carefully evaluated for evidence of epigenetic modification of T-DNA before final conclusions are drawn. [ABSTRACT FROM AUTHOR]

Several xylem-associated regulatory genes have been identified that control processes associated with wood formation in poplar. Prominent among these are the NAC domain transcription factors (NACs). Here, the putative involvement of Populus NAC154 , a co-ortholog of the Arabidopsis gene SND2 , was evaluated as a regulator of “secondary” biosynthetic processes in stem internode tissues by interrogating aqueous methanolic extracts from control and transgenic trees. Comprehensive untargeted metabolite profiling was accomplished with a liquid chromatography–mass spectrometry platform that utilized two different chromatographic supports (HILIC and reversed phase) and both positive and negative ionization modes. Evaluation of current and previous year tissues provided datasets for assessing the effects of NAC154 overexpression in wood maturation processes. Phenolic glycoside levels as well as those of oligolignols, sucrose and arginine were modulated with phenotypic and chemotypic traits exhibiting similar trends. Specifically, increased levels of arginine in the NAC154 overexpressing tissues supports a role for the transcription factor in senescence/dormancy-associated processes. [ABSTRACT FROM AUTHOR]

Forest trees are dominant components of terrestrial ecosystems that have global ecological and economic importance. Despite distributions that span wide environmental gradients, many tree populations are locally adapted, and mechanisms underlying this adaptation are poorly understood. Here we use a combination of whole-genome selection scans and association analyses of 544 Populus trichocarpa trees to reveal genomic bases of adaptive variation across a wide latitudinal range. Three hundred ninety-seven genomic regions showed evidence of recent positive and/or divergent selection and enrichment for associations with adaptive traits that also displayed patterns consistent with natural selection. These regions also provide unexpected insights into the evolutionary dynamics of duplicated genes and their roles in adaptive trait variation. [ABSTRACT FROM AUTHOR]