Picture of two heads

Open Access research that challenges the mind...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including those from the School of Psychological Sciences & Health - but also papers by researchers based within the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

Synthesis of vesicle cargo determines amplitude of Ca2+-sensitive exocytosis

Sutter, Jens and Denecke, Juergen and Thiel, Gerhard (2012) Synthesis of vesicle cargo determines amplitude of Ca2+-sensitive exocytosis. Cell Calcium, 52 (3-4). pp. 283-288. ISSN 0143-4160

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Here we examine the potential coupling between the synthesis of secretory proteins and the sensitivity of exocytosis to the concentration of free Ca2+ in the cytosol ([Ca2+](i)) in plant cell. We therefore monitor in tobacco protoplasts the excursion of the membrane capacitance in response to an elevation of[Ca2+](i) as a measure for exocytotic activity. The data show that a ramp like elevation of [Ca2+](i) generates in protoplasts from wild type plants and from transgenic plants, which overexpress the secreted alpha-amylase, an exocytotic burst with an initial steep and a subsequent slow phase. The largest capacitive burst is obtained in alpha-amylase producing plants and the amplitude of the [Ca2+](i) evoked C-m excursion is a function of the amylase synthesis of the plants. The data support a model according to which plant cells have at least two serial [Ca2+](i) sensitive processes in the final steps of their exocytotic pathway. The overproduction of a secreted cargo does not affect the kinetics of this process but the number of vesicles in pools upstream of the [Ca2+](i) sensitive steps. (C) 2012 Elsevier Ltd. All rights reserved.