In situ assessment of mitochondrial calcium transport in tobacco pollen tubes
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Pollen tubes require functional mitochondria in order to achieve fast and sustained growth. In addition, cell wall expansion requires a calcium gradient in the tube apex formed by a dedicated array of calcium pumps and channels. Most studies have traditionally focused on the molecular aspects of calcium interactions and transport across the pollen tube plasmalemma. However, calcium transients across mitochondrial membranes from pollen tubes are beginning to be studied. Here, we report the presence of a ruthenium red-sensitive mitochondrial calcium uniporter-like activity in tobacco pollen tubes with functional oxidative phosphorylation. The present study provides a framework to measure in situ specifics of mitochondrial transport and respiration in pollen tubes from different plants. The relevance of a mitochondrial calcium uniporter for pollen tube growth is discussed.
KeywordsPollen tubes Nicotiana Mitochondrial calcium uniporter Transport Digitonin
mitochondrial calcium uniporter
Arabidopsis thaliana mitochondrial calcium uniporter 1
Arabidopsis thaliana mitochondrial calcium uniporter 2
EF-hand MCU regulator
mitochondrial permeability transition
pollen tube assay
reactive oxygen species
This work was supported by grant UNAM-FQ-PAIP 5000-9171 (to M.G.-A.). We would like to thank Dr. Sobeida Sánchez-Nieto and Dr. Felipe Cruz-García for providing valuable material resources and advice for the completion of this study.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Baughman JM, Perocchi F, Girgis HS, Plovanich M, Belcher-Timme CA, Sancak Y, Bao XR, Strittmatter L, Goldberger O, Bogorad RL, Koteliansky V, Mootha VK (2011) Integrative genomics identifies MCU as an essential component of the mitochondrial calcium uniporter. Nature 476:341–345. https://doi.org/10.1038/nature10234 CrossRefPubMedPubMedCentralGoogle Scholar
- Iwano M, Entani T, Shiba H, Kakita M, Nagai T, Mizuno H, Miyawaki A, Shoji T, Kubo K, Isogai A, Takayama S (2009) Fine-tuning of the cytoplasmic Ca2+ concentration is essential for pollen tube growth. Plant Physiol 150:1322–1334. https://doi.org/10.1104/pp.109.139329 CrossRefPubMedPubMedCentralGoogle Scholar
- Loro G, Drago I, Pozzan T, Schiavo FL, Zottini M, Costa A (2012) Targeting of Cameleons to various subcellular compartments reveals a strict cytoplasmic/mitochondrial Ca(2)(+) handling relationship in plant cells. Plant J 71:1–13. https://doi.org/10.1111/j.1365-313X.2012.04968.x CrossRefPubMedGoogle Scholar
- Pan X, Liu J, Nguyen T, Liu C, Sun J, Teng Y, Fergusson MM, Rovira II, Allen M, Springer DA, Aponte AM, Gucek M, Balaban RS, Murphy E, Finkel T (2013) The physiological role of mitochondrial calcium revealed by mice lacking the mitochondrial calcium uniporter. Nat Cell Biol 15:1464–1472. https://doi.org/10.1038/ncb2868 CrossRefPubMedPubMedCentralGoogle Scholar
- Sommakia S, Houlihan PR, Deane SS, Simcox JA, Torres NS, Jeong MY, Winge DR, Villanueva CJ, Chaudhuri D (2017) Mitochondrial cardiomyopathies feature increased uptake and diminished efflux of mitochondrial calcium. J Mol Cell Cardiol 113:22–32. https://doi.org/10.1016/j.yjmcc.2017.09.009 CrossRefPubMedGoogle Scholar
- Teardo E, Carraretto L, Wagner S, Formentin E, Behera S, de Bortoli S, Larosa V, Fuchs P, Lo Schiavo F, Raffaello A, Rizzuto R, Costa A, Schwarzländer M, Szabò I (2017) Physiological characterization of a plant mitochondrial calcium uniporter in vitro and in vivo. Plant Physiol 173:1355–1370. https://doi.org/10.1104/pp.16.01359 CrossRefPubMedGoogle Scholar
- Waese J, Fan J, Pasha A, Yu H, Fucile G, Shi R, Cumming M, Kelley LA, Sternberg MJ, Krishnakumar V, Ferlanti E, Miller J, Town C, Stuerzlinger W, Provart NJ (2017) ePlant: visualizing and exploring multiple levels of data for hypothesis generation in plant biology. Plant Cell 29:1806–1821. https://doi.org/10.1105/tpc.17.00073 CrossRefPubMedPubMedCentralGoogle Scholar