Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch

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Investigations into a putative role for the novel BRASSIKIN pseudokinases in compatible pollen-stigma interactions in Arabidopsis thaliana.

BACKGROUND: In the Brassicaceae, the early stages of compatible pollen-stigma interactions are tightly controlled with early checkpoints regulating pollen adhesion, hydration and germination, and pollen tube entry into the stigmatic surface. However, the early signalling events in the stigma which trigger these compatible interactions remain unknown. RESULTS: A set of stigma-expressed pseudokinase genes, termed BRASSIKINs (BKNs), were identified and found to be present in only core Brassicaceae genomes. In Arabidopsis thaliana Col-0, BKN1 displayed stigma-specific expression while the BKN2 gene was expressed in other tissues as well. CRISPR deletion mutations were generated for the two tandemly linked BKNs, and very mild hydration defects were observed for wild-type Col-0 pollen when placed on the bkn1/2 mutant stigmas. In further analyses, the predominant transcript for the stigma-specific BKN1 was found to have a premature stop codon in the Col-0 ecotype, but a survey of the 1001 Arabidopsis genomes uncovered three ecotypes that encoded a full-length BKN1 protein. Furthermore, phylogenetic analyses identified intact BKN1 orthologues in the closely related outcrossing Arabidopsis species, A. lyrata and A. halleri. Finally, the BKN pseudokinases were found to be plasma-membrane localized through the dual lipid modification of myristoylation and palmitoylation, and this localization would be consistent with a role in signaling complexes. CONCLUSION: In this study, we have characterized the novel Brassicaceae-specific family of BKN pseudokinase genes, and examined the function of BKN1 and BKN2 in the context of pollen-stigma interactions in A. thaliana Col-0. Additionally, premature stop codons were identified in the predicted stigma specific BKN1 gene in a number of the 1001 A. thaliana ecotype genomes, and this was in contrast to the out-crossing Arabidopsis species which carried intact copies of BKN1. Thus, understanding the function of BKN1 in other Brassicaceae species will be a key direction for future studies

Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch

Silver birch (Betula pendula) is a pioneer boreal tree that can be induced to flower within 1 year. Its rapid life cycle, small (440-Mb) genome, and advanced germplasm resources make birch an attractive model for forest biotechnology. We assembled and chromosomally anchored the nuclear genome of an inbred B. pendula individual. Gene duplicates from the paleohexaploid event were enriched for transcriptional regulation, whereas tandem duplicates were overrepresented by environmental responses. Population resequencing of 80 individuals showed effective population size crashes at major points of climatic upheaval. Selective sweeps were enriched among polyploid duplicates encoding key developmental and physiological triggering functions, suggesting that local adaptation has tuned the timing of and cross-talk between fundamental plant processes. Variation around the tightly-linked light response genes PHYC and FRS10 correlated with latitude and longitude and temperature, and with precipitation for PHYC. Similar associations characterized the growth-promoting cytokinin response regulator ARR1, and the wood development genes KAK and MED5A.Peer reviewe

Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch.

Silver birch (Betula pendula) is a pioneer boreal tree that can be induced to flower within 1 year. Its rapid life cycle, small (440-Mb) genome, and advanced germplasm resources make birch an attractive model for forest biotechnology. We assembled and chromosomally anchored the nuclear genome of an inbred B. pendula individual. Gene duplicates from the paleohexaploid event were enriched for transcriptional regulation, whereas tandem duplicates were overrepresented by environmental responses. Population resequencing of 80 individuals showed effective population size crashes at major points of climatic upheaval. Selective sweeps were enriched among polyploid duplicates encoding key developmental and physiological triggering functions, suggesting that local adaptation has tuned the timing of and cross-talk between fundamental plant processes. Variation around the tightly-linked light response genes PHYC and FRS10 correlated with latitude and longitude and temperature, and with precipitation for PHYC. Similar associations characterized the growth-promoting cytokinin response regulator ARR1, and the wood development genes KAK and MED5A

Task Allocation Algorithm for Energy Resources Providing Frequency Containment Reserves

The uncertainty caused by the variability in renewable energy production requires the engagement of consumer-side energy production and consumption to provide sufficient flexibility and reliability for the power grid. This study presents an algorithm for allocating tasks to distributed energy resources allowing consumers to provide flexibility for frequency containment reserves. The task allocation algorithm aims at supporting the plug and play of energy resources, and it avoids the need for hard real-time messages during the coordination of the resources. The algorithm combines a novel control strategy with an information and communication technology architecture. The main decision logic of the algorithm is defined together with the distributed control logic. A prototype implementation of the overall system for frequency control is used to evaluate the performance of the algorithm. The simulation results show that the algorithm achieves the specified objectives, and has advantages compared to the state of the art solution.Peer reviewe

An Integrated Implementation Methodology of a Lifecycle-wide Tracking Simulation Architecture

A tracking simulator is a decision support application in which dynamic estimation is used to continuously align the results of an online first principle simulation model with the measurements of the targeted plant. They are a holistic application where current and future plant information is available for operation support of process plants. Existing tracking simulators have focused on the application of online and offline methods for estimation of their underlying first principle models (FPMs). However, these systems have been less attractive than similar alternatives based on empirical modelling, due to the lack of systematic approaches that address challenges across the tracking simulation lifecycle, such as laborious development of FPMs as well as high integration costs with the process or with other systems and simulation methods. In contrast, the approach presented in this work integrates a tracking simulation architecture and various simulation methods to address the described challenges as follows. In order to tackle time-consuming development of FPMs, a method for generating tracking simulation models from models created during design phase is proposed. The process of connecting the tracking simulator to the physical plant and initializing the tracking simulator is automated. An optimization method for tracking simulation applications is developed to overcome drawbacks of available methods. The simulation architecture developed applies the proposed methodology during the various phases of tracking simulation. Furthermore, it exploits industrial communication standards to avoid the need for point-to-point integration of various simulators and other systems used over the course of the tracking simulator lifecycle. The work is demonstrated with laboratory process equipment.Peer reviewe