Ioannis-Dimosthenis S. Adamakis, Eleftherios P. Eleftheriou
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引用次数: 0
Key message
MAP65-1 phosphorylation mediates Cr(VI)-induced microtubule disruption in plants.
Abstract
Chromium (Cr) exists in two prevalent forms in the environment: trivalent Cr(III) and hexavalent Cr(VI). While Cr(III) can benefit plants as a micronutrient, Cr(VI) is highly toxic and disrupts essential physiological, biochemical, and cellular processes in plants. Plant cell microtubules (MTs) are particularly susceptible to Cr(VI) toxicity, with MAP65-1, a key microtubule-associated protein, playing a crucial role in stabilizing MTs by forming cross-bridges between them. The stability function of MAP65-1 is influenced by its phosphorylation status: phosphorylation causes MAP65-1 to detach from MTs during different cell cycle phases. This study investigated how Cr(VI) affects MAP65-1 presence on cortical MTs in Arabidopsis thaliana roots and hypocotyls. Seedlings expressing GFP:AtMAP65-1 and its non-phosphorylatable variant, AtMAP65-19A (GFP:AtMAP65-19A), were exposed to 100 μM potassium dichromate (K2Cr2O7, Cr(VI)) on ½ MS solid medium for 24 or 48 h. Confocal laser scanning microscopy (CLSM) revealed that Cr(VI) began impacting cortical MTs within 24 h. The signal intensity of GFP indicated a significant reduction in MAP65-1 presence, whereas the GFP:AtMAP65-19A signal remained stable and MTs were unaffected. These results suggest that Cr(VI) toxicity to MTs is linked to MAP65-1’s phosphorylation status.
期刊介绍：
Acta Physiologiae Plantarum is an international journal established in 1978 that publishes peer-reviewed articles on all aspects of plant physiology. The coverage ranges across this research field at various levels of biological organization, from relevant aspects in molecular and cell biology to biochemistry.
The coverage is global in scope, offering articles of interest from experts around the world. The range of topics includes measuring effects of environmental pollution on crop species; analysis of genomic organization; effects of drought and climatic conditions on plants; studies of photosynthesis in ornamental plants, and more.
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