Data/Software for "Presynaptic Mitochondria Volumes and Complexity of Subsynaptic Distribution Increase During Development at a High-fidelity Synapse"
Description
Contains data and software from the publication: "Presynaptic Mitochondria Volumes and Complexity of Subsynaptic Distribution Increase During Development at a High-fidelity Synapse" currently under review. In this study, we created a helper-dependent adenoviral vector (HdAd) to co-express cytoplasmic EGFP and a genetically encoded peroxidase marker (mito-APEX2) at the calyx of Held, an excellent model for deciphering regulatory mechanisms of presynaptic function. ABSTRACT: The calyx of Held, a large glutamatergic presynaptic terminal in the auditory brainstem undergoes developmental changes to support the high action-potential firing rates required for auditory information encoding. In addition, calyx terminals are morphologically diverse which impacts vesicle release properties and synaptic plasticity. Mitochondria influence synaptic plasticity through calcium buffering and are crucial for providing the energy required for synaptic transmission. Therefore, it has been postulated that mitochondrial levels increase during development and contribute to the morphological-functional diversity in the mature calyx. However, the developmental profile of mitochondrial volumes and subsynaptic distribution at the calyx of Held remains unclear. To provide insight on this, we developed a helper-dependent adenoviral vector (HdAd) that expresses the genetically encoded peroxidase marker for mitochondria, mito-APEX, at the mouse calyx of Held. We developed protocols to detect labeled mitochondria for use serial block face SEM (SBF-SEM) to carry out semi-automated segmentation of mitochondria, high-throughput whole terminal reconstruction and presynaptic ultrastructure in mice of either sex. Subsequently, we measured mitochondrial volumes and subsynaptic distributions at the immature postnatal day 7 (P7) and the mature (P21) calyx. We found an increase of mitochondria volumes in terminals and axons from P7 to P21 but did not observe differences between stalk and swelling subcompartments in the mature calyx. Based on these findings, we propose that mitochondrial volumes developmentally increase to support high firing rates but have limited contribution to morphological-functional diversity at the calyx. Data are sorted by the figures they appear in and custom-written software is located in a separate folder.
Files
Steps to reproduce
All data are stored in CSV-files with periods as decimal point and columns separated by commas. The first line in the CSV file corresponds to the header which identifies the groups.