Redistribution of actin, profilin and phosphatidylinositol-4,5-bisphosphate in growing and maturing root hairs
| العنوان: | Redistribution of actin, profilin and phosphatidylinositol-4,5-bisphosphate in growing and maturing root hairs |
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| المؤلفون: | von Witsch M, Markus Braun, František Baluška, D Menzel |
| المصدر: | Planta. 209:435-443 |
| بيانات النشر: | Springer Science and Business Media LLC, 1999. |
| سنة النشر: | 1999 |
| مصطلحات موضوعية: | biology, Actin remodeling, macromolecular substances, Plant Science, Root hair, Microfilament, Actin remodeling of neurons, Profilin, Biochemistry, Genetics, biology.protein, Biophysics, MDia1, Tip growth, Cytoskeleton |
| الوصف: | The continuously changing polar cytoplasmic organization during initiation and tip growth of root hairs is reflected by a dynamic redistribution of cytoskeletal elements. The small G-actin binding protein, profilin, which is known to be a widely expressed, potent regulator of actin dynamics, was specifically localized at the tip of root hairs and co-distributed with a diffusely fluorescing apical cap of actin, but not with subapical actin microfilament (MF) bundles. Profilin and actin caps were present exclusively in the bulge of outgrowing root hairs and at the apex of elongating root hairs; both disappeared when tip growth terminated, indicating a tip-growth mechanism that involves profilin-actin interactions for the delivery and localized exocytosis of secretory vesicles. Phosphatidylinositol-4,5-bisphosphate (PIP(2)), a ligand of profilin, was localized almost exclusively in the bulge and, subsequently, formed a weak tip-to-base gradient in the elongating root hairs. When tip growth was eliminated by the MF-disrupting inhibitor cytochalasin D, the apical profilin and the actin fluorescence were lost. Mastoparan, which is known to affect the PIP(2) cycle, probably by stimulating phospholipases, caused the formation of a meshwork of distinct actin MFs replacing the diffuse apical actin cap and, concomittantly, tip growth stopped. This suggests that mastoparan interferes with the PIP(2)-regulated profilin-actin interactions and hence disturbs conditions indispensable for the maintenance of tip growth in root hairs. |
| تدمد: | 1432-2048 0032-0935 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c90b69dcbaef2efd793a8f4d37813d97Test https://doi.org/10.1007/s004250050746Test |
| حقوق: | CLOSED |
| رقم الانضمام: | edsair.doi.dedup.....c90b69dcbaef2efd793a8f4d37813d97 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 14322048 00320935 |
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