Polar tip growth of pollen tubes is regulated by the membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P), which localizes in a well-defined region of the subapical plasma membrane. How the PtdIns(4,5)P region is maintained is currently unclear. In principle, the formation of PtdIns(4,5)P by PI4P 5-kinases can be counteracted by phospholipase C (PLC), which hydrolyzes PtdIns(4,5)P. Here, we show that fluorescence-tagged tobacco NtPLC3 displays a subapical plasma membrane distribution which frames that of fluorescence-tagged PI4P 5-kinases, suggesting that NtPLC3 may modulate PtdIns(4,5)P-mediated processes in pollen tubes. The expression of a dominant negative NtPLC3 variant resulted in pollen tube tip swelling, consistent with a delimiting effect on PtdIns(4,5)P production. When pollen tube morphologies were assessed as a quantitative read-out for PtdIns(4,5)P function, NtPLC3 reverted the effects of a coexpressed PI4P 5-kinase, demonstrating that NtPLC3-mediated breakdown of PtdIns(4,5)P antagonizes the effects of PtdIns(4,5)P overproduction in vivo. When analyzed by spinning disc microscopy, fluorescence-tagged NtPLC3 displayed discontinuous membrane distribution omitting punctate areas of the membrane, suggesting that NtPLC3 is involved in the spatial restriction of plasma membrane domains also at the nanodomain scale. Together, the data indicate that NtPLC3 may contribute to the spatial restriction of PtdIns(4,5)P in the subapical plasma membrane of pollen tubes.
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http://dx.doi.org/10.3390/plants9040452 | DOI Listing |
ACS Nano
January 2025
Department of Orthopedics, The First Affiliated Hospital of Soochow University, 899 Pinghai Road, Soochow, Jiangsu 215000, China.
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January 2025
Department of Biotechnology and Biophysics, Biocenter, University of Würzburg, Würzburg, Germany.
Elucidating the interaction between membrane proteins and antibodies requires whole-cell imaging at high spatiotemporal resolution. Lattice light-sheet (LLS) microscopy offers fast volumetric imaging but suffers from limited spatial resolution. DNA-based point accumulation for imaging in nanoscale topography (DNA-PAINT) achieves molecular resolution but is restricted to two-dimensional imaging owing to long acquisition times.
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December 2024
Institute of Cardiovascular Sciences, University College London, London, UK.
Background: While most thyroid nodules are benign, 7-15% are malignant. Patients with indeterminate thyroid nodules (specifically Bethesda IV/Thy3f) often undergo diagnostic hemithyroidectomy to reach a diagnosis on final histology. The aim of this study was to assess the feasibility of circulating large extracellular vesicles as diagnostic biomarkers in patients presenting with Thy3f thyroid nodules.
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January 2025
Department of Biomedical and Molecular Sciences, Queen's University.
Purpose Of Review: To date, there is relatively limited research investigating changes in red blood cells (RBCs), particularly qualitative changes, in cancer patients and cancer patients receiving treatment. These changes may be important in better understanding cancer-associated anemia, which is the most prevalent hematological disorder in cancer patients with wide-ranging implications on patient care and quality of life. This review aims to summarize available evidence regarding qualitative and quantitative changes in RBCs in individuals with cancer prior to treatment and in patients undergoing treatment.
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