PKA activation bypasses the requirement for UNC-31 in the docking of dense core vesicles from C. elegans neurons

Ke-Ming Zhou; Yong-Ming Dong; Qian Ge; Dan Zhu; Wei Zhou; Xian-Guang Lin; Tao Liang; Zheng-Xing Wu; Tao Xu

doi:10.1016/j.neuron.2007.09.015

PKA activation bypasses the requirement for UNC-31 in the docking of dense core vesicles from C. elegans neurons

Neuron. 2007 Nov 21;56(4):657-69. doi: 10.1016/j.neuron.2007.09.015.

Authors

Ke-Ming Zhou¹, Yong-Ming Dong, Qian Ge, Dan Zhu, Wei Zhou, Xian-Guang Lin, Tao Liang, Zheng-Xing Wu, Tao Xu

Affiliation

¹ Key Laboratory of Molecular Biophysics, Ministry of Education, and Joint Laboratory of Institute of Biophysics, Huazhong University of Science and Technology, Wuhan 430074, China.

PMID: 18031683
DOI: 10.1016/j.neuron.2007.09.015

Abstract

The nematode C. elegans provides a powerful model system for exploring the molecular basis of synaptogenesis and neurotransmission. However, the lack of direct functional assays of release processes has largely prevented an in depth understanding of the mechanism of vesicular exocytosis and endocytosis in C. elegans. We address this technical limitation by developing direct electrophysiological assays, including membrane capacitance and amperometry measurements, in primary cultured C. elegans neurons. In addition, we have succeeded in monitoring the docking and fusion of single dense core vesicles (DCVs) employing total internal reflection fluorescence microscopy. With these approaches and mutant perturbation analysis, we provide direct evidence that UNC-31 is required for the docking of DCVs at the plasma membrane. Interestingly, the defect in DCV docking caused by UNC-31 mutation can be fully rescued by PKA activation. We also demonstrate that UNC-31 is required for UNC-13-mediated augmentation of DCV exocytosis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Caenorhabditis elegans / metabolism*
Caenorhabditis elegans / ultrastructure
Caenorhabditis elegans Proteins / metabolism*
Calcium-Binding Proteins / metabolism*
Carrier Proteins
Cell Membrane / metabolism
Cells, Cultured
Cyclic AMP-Dependent Protein Kinases / metabolism*
Enzyme Activation / physiology
Exocytosis / physiology
Green Fluorescent Proteins
Intracellular Membranes / metabolism
Membrane Fusion / physiology
Nervous System / metabolism*
Nervous System / ultrastructure
Neurons / metabolism*
Neurons / ultrastructure
Neurosecretion / physiology
Neurotransmitter Agents / metabolism
Secretory Vesicles / metabolism*
Secretory Vesicles / ultrastructure
Serotonin / metabolism
Synaptic Membranes / metabolism
Synaptic Transmission / physiology

Substances

Caenorhabditis elegans Proteins
Calcium-Binding Proteins
Carrier Proteins
Neurotransmitter Agents
UNC-31 protein, C elegans
phorbol ester binding protein
Green Fluorescent Proteins
Serotonin
Cyclic AMP-Dependent Protein Kinases