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.
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