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Grill, E.

Publications and source records attributed to Grill, E..

2 recordsLinked to original sources

Who gets lost and why: A representative cross-sectional survey on sociodemographic and vestibular determinants of wayfinding strategies

When we think of our family and friends, we probably know someone who is good at finding their way and someone else that easily get lost. We still know little about the biological and environmental factors that influence our navigational ability. Here, we investigated the frequency and sociodemographic determinants of wayfinding and their association with vestibular function in a representative cross-sectional sample (N = 783) of the adult German-speaking population. Wayfinding was assessed using the Wayfinding Strategy Scale, a self-report scale that produces two scores for each participant representing to what degree they rely on route-based or orientation (map-based) strategies. We were interested in the following research questions: (1) the frequency and determinants of wayfinding strategies in a population-based representative sample, (2) the relationship between vestibular function and strategy choice and (3) how sociodemographic factors influence general wayfinding ability as measured using a combined score from both strategy scores. Our linear regression models showed that being male, having a higher education, higher age and lower regional urbanization increased orientation strategy scores. Vertigo/dizziness reduced the scores of both the orientation and the route strategies. Using a novel approach, we grouped participants by their combined strategy scores in a multinomial regression model, to see whether individuals prefer one strategy over the other. The majority of individuals reported using either both or no strategy, instead of preferring one strategy over the other. Young age and reduced vestibular function were indicative of using no strategy. In summary, wayfinding ability depends on both biological and environmental factors; all sociodemographic factors except income. Over a third of the population, predominantly under the age of 35, does not successfully use either strategy. This represents a change in our wayfinding skills, which may result from the technological advances in navigational aids over the last few decades.

neuroscience

Fine-tuning of ABA responses by the protein kinase WNK8

The phytohormone abscisic acid (ABA) regulates various growth- and developmental processes in response to limiting water conditions. ABA functions through an established signaling pathway consisting of PYR1/PYL/RCAR ABA receptors that inhibit group A type 2C protein phosphatases (PP2Cs) in an ABA-dependent manner. Inhibition of PP2Cs enables the activation of SnRK2-type protein kinases that phosphorylate downstream targets including transcription factors and ion channels. However, ABA-dependent signals have to be integrated into other growth- and developmental programs to ensure a successful life cycle. Here, we have characterized the role of the protein kinase WNK8 in the ABA signalling pathway. Two T-DNA insertion alleles wnk8-1 and wnk8-4 exhibited contrasting ABA responses during seed germination and young seedling growth. However, reciprocal crossings with wild type plants suggested that wnk8-1 that still expressed the WNK8 kinase domain functioned in a hypermorphic and dominant manner. WNK8 directly interacted with the PP2C PP2CA in planta and was negatively regulated by this phosphatase in vitro. WNK8 also phosphorylated the ABA receptor PYR1 in vitro. Double mutant analyses revealed that the dominant allele wnk8-1 suppressed the ABA- and glucose hypersensitivity of the pp2ca-1 T-DNA allele. In transient protoplast assays WNK8 suppressed ABA-induced reporter gene expression that was dependent on a functional kinase. In summary, we have identified the protein kinase WNK8 as a negative regulator of ABA responses during young seedling establishment through its direct interaction with core ABA signaling components.\n\nSIGNIFICANCE STATEMENTThe phytohormone abscisic acid regulates the water household of plants through a defined core signaling pathway. Here we have identified the protein kinase WNK8 as a direct interactor of core abscisic acid signalling components and as a negative modulator of abscisic acid responses during young seedling development in Arabidopsis.

plant biology