Floral organs are modified leaves, but ectopic expression of ABC genes not led to flower, indicates insufficient genes for flower devt.
The TPD1 protein is secreted and binds to the EMS1 receptors on the neighboring cells, causing an elevation of EMS1 levels in these cells and a drop in TPD1 levels. EMS1 then activates a pathway for tapetal differentiation.
Epidermal and endothecium cells of the anther lose some of their starch and start tangential and radial expansion, which is then followed by endothecial secondary thickening
During stomium degeneration the calcium oxalate is released from the circular cell cluster onto the pollen and is subsequently transferred to the stigma upon pollination. The role of calcium oxalate has not been fully established, but it has been suggested that it provides calcium ions required for the pollen germination
PCS1 encodes aspartic protease acts in the ER either by processing and activating a ‘survival factor’, or by processing and inactivating a pro-PCD component that prevents PCD
dad1 mutant the stomium fails to open and elongation of the filament is delayed; however, other features required for dehiscence, such as tapetal degeneration, septum breakdown, endothecium thickening, and formation of trinucleate pollen, occur normally
