Publications by authors named "Hanna Help-Rinta-Rahko"
Article Synopsis
- Pattern formation in plants is influenced by molecular signals, particularly the hormone auxin, which affects the development of vascular structures during embryonic growth, resulting in specific patterns like the uncommon diarch xylem structure.* -
- Multiscale mathematical modeling reveals that the diarch pattern does not necessarily require varied auxin input, as it can emerge dynamically based on spatial constraints and growth factors.* -
- The model's predictions align with experimental data on xylem pole numbers across various plant species, providing insight into the diversity of vascular structures in flowering plants.*
Article Synopsis
- Seed germination triggers apical growth in plants, while radial growth is initiated earlier in procambium cells and later activated by vascular cambium, showing similarities to certain animal developmental processes.
- In Arabidopsis, radial growth starts in the root procambial tissue, specifically in the early protophloem-sieve-element cell files, where cytokinin signaling activates a pair of transcription factors (PEAR1 and PEAR2) and their homologues (collectively named PEAR proteins).
- These PEAR proteins create a concentration gradient that enhances gene expression for radial growth, while their function is counteracted by HD-ZIP III proteins which, regulated by auxin and microRNAs, establish a negative-feedback loop that helps distinguish
An auxin maximum is positioned along the xylem axis of the Arabidopsis root tip. The pattern depends on mutual feedback between auxin and cytokinins mediated by the PIN class of auxin efflux transporters and AHP6, an inhibitor of cytokinin signalling. This interaction has been proposed to regulate the size and the position of the hormones' respective signalling domains and specify distinct boundaries between them.
View Article and Find Full Text PDFRecognition of extracellular peptides by plasma membrane-localized receptor proteins is commonly used in signal transduction. In plants, very little is known about how extracellular peptides are processed and activated in order to allow recognition by receptors. Here, we show that induction of cell death in planta by a secreted plant protein GRIM REAPER (GRI) is dependent on the activity of the type II metacaspase METACASPASE-9.
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