Phyllotaxis describes the periodic arrangement of plant organs most conspicuously floral. Oscillators generally underlie periodic phenomena. A hypothetical algorithm generates phyllotaxis regulated by the Hechtian growth oscillator of the stem apical meristem (SAM) protoderm. The oscillator integrates biochemical and mechanical force that regulate morphogenetic gradients of three ionic species, auxin, protons and Ca. Hechtian adhesion between cell wall and plasma membrane transduces wall stress that opens Ca channels and reorients auxin efflux "PIN" proteins; they control the auxin-activated proton pump that dissociates Ca bound by periplasmic arabinogalactan proteins (AGP-Ca) hence the source of cytosolic Ca waves that activate exocytosis of wall precursors, AGPs and PIN proteins essential for morphogenesis. This novel approach identifies the critical determinants of an algorithm that generates phyllotaxis spiral and Fibonaccian symmetry: these determinants in order of their relative contribution are: (1) size of the apical meristem and the AGP-Ca capacitor; (2) proton pump activity; (3) auxin efflux proteins; (4) Ca channel activity; (5) Hechtian adhesion that mediates the cell wall stress vector. Arguably, AGPs and the AGP-Ca capacitor plays a decisive role in phyllotaxis periodicity and its evolutionary origins.
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http://dx.doi.org/10.3390/ijms21031145 | DOI Listing |
Microbiome
January 2025
Department of Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Beutenbergstraße 11A, Jena, 07745, Germany.
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BMC Genom Data
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Department of Management Information Systems, National Chung Hsing University, Taichung, 402, Taiwan.
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View Article and Find Full Text PDFBMC Bioinformatics
January 2025
Department of Chemistry, University of Louisiana at Lafayette, Lafayette, LA, 70504, USA.
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View Article and Find Full Text PDFBehav Res Methods
January 2025
Department of Data Analysis, Ghent University, Henri Dunantlaan 1, 9000, Ghent, Belgium.
Model estimation for SEM analyses in commonly used software typically involves iterative optimization procedures, which can lead to nonconvergence issues. In this paper, we propose using random starting values as an alternative to the current default strategies. By drawing from uniform distributions within data-driven lower and upper bounds (see De Jonckere et al.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China.
The conventional statistical approach for analyzing resting state functional MRI (rs-fMRI) data struggles to accurately distinguish between patients with multiple sclerosis (MS) and those with neuromyelitis optic spectrum disorders (NMOSD), highlighting the need for improved diagnostic efficacy. In this study, multilevel functional metrics including resting state functional connectivity, amplitude of low frequency fluctuation (ALFF), and regional homogeneity (ReHo) were calculated and extracted from 116 regions of interest in the anatomical automatic labeling atlas. Subsequently, classifiers were developed using different combinations of these selected features to distinguish between MS and NMOSD.
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