Related Experiment Video
Updated: Mar 12, 2026

Forward Genetic Screen Using Transgenic Calcium Reporter Aequorin to Identify Novel Targets in Calcium Signaling
Published on: August 1, 2020
MONENSIN SENSITIVITY1 (MON1)/CALCIUM CAFFEINE ZINC SENSITIVITY1 (CCZ1)-Mediated Rab7 Activation Regulates Tapetal
Yong Cui1,2,3,4, Qiong Zhao1,2,3,4, Hong-Tao Xie1,2,3,4
1School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (Y.C., Q.Z., W.S.W., X.W., C.G., Y.D., Y.T., L.J.).
Abstract:
Programmed cell death (PCD)-triggered degradation of plant tapetum is essential for microspore development and pollen coat formation; however, little is known about the cellular mechanism regulating tapetal PCD Here, we demonstrate that Rab7-mediated vacuolar transport of tapetum degradation-related cysteine proteases is crucial for tapetal PCD and pollen development in Arabidopsis (Arabidopsis thaliana), with the following evidence: (1) The monensin sensitivity1 (mon1) mutants, which are defective in Rab7 activation, showed impaired male fertility due to a combined defect in both tapetum and male gametophyte development. (2) In anthers, MON1 showed preferential high level expression in tapetal cell layers and pollen. (3) The mon1 mutants exhibited delayed tapetum degeneration and tapetal PCD, resulting in abnormal pollen coat formation and decreased male fertility. (4) MON1/CALCIUM CAFFEINE ZINC SENSITIVITY1 (CCZ1)-mediated Rab7 activation was indispensable for vacuolar trafficking of tapetum degradation-related cysteine proteases, supporting that PCD-triggered tapetum degeneration requires Rab7-mediated vacuolar trafficking of these cysteine proteases. (5) MON1 mutations also resulted in defective pollen germination and tube growth. Taken together, tapetal PCD and pollen development require successful MON1/CCZ1-mediated vacuolar transport in Arabidopsis.
More Related Videos
13:40Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms
Published on: July 7, 2011
12:18A Strategy to Validate the Role of Callose-mediated Plasmodesmal Gating in the Tropic Response
Published on: April 17, 2016
Related Concept Videos
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Cell Signaling in Plants
Non-Canonical Wnt Signaling Pathways
Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...