Cytosolic free calcium mediates red light-induced photomorphogenesis

Spatial characteristics to calcium signalling; the calcium wave as a basic unit in plant cell calcium signalling

“…Many £uorescent ratio images of pollen tubes, protoplasts and guard cells have been produced (Gilroy et al 1991;Shacklock et al 1992;Malho¨et al 1994 A total of three main kinetic characteristics of the transient can be recognized; the rise time, the peak and the decay time. The rise time represents a period of increasing recruitment of vesicles into a release mode; in this phase, Ca 2+ release is greater than Ca 2+ uptake.…”

Second Messengers Mediate Increases in Cytosolic Calcium in Tobacco Protoplasts

“…Increases in [Ca 2ϩ ] cyt produced either by influx or release from internal Ca 2ϩ stores stimulate the phosphorylation of proteins within the cell (Poovaiah and Reddy, 1990). An increase in [Ca 2ϩ ] cyt detected by Ca 2ϩ microelectrodes, Ca 2ϩ -sensitive fluorescence probes, and extrinsic and intrinsic aequorin (Cobbold and Rink, 1987;Chae et al, 1990;Knight et al, 1991;Shacklock et al, 1992), followed by the alteration of the activities of intercellular targets, enzymes, genes, pumps, and channels, have all been demonstrated in plants (Fallon et al, 1993;Neuhaus et al, 1993;Bowler et al, 1994a). In some circumstances activated plant cells can display repeated Ca 2ϩ spikes or oscillations (McAinsh et al, 1995) and spreading Ca 2ϩ waves (Shacklock et al, 1992;Campbell et al, 1996).…”

“…An increase in [Ca 2ϩ ] cyt detected by Ca 2ϩ microelectrodes, Ca 2ϩ -sensitive fluorescence probes, and extrinsic and intrinsic aequorin (Cobbold and Rink, 1987;Chae et al, 1990;Knight et al, 1991;Shacklock et al, 1992), followed by the alteration of the activities of intercellular targets, enzymes, genes, pumps, and channels, have all been demonstrated in plants (Fallon et al, 1993;Neuhaus et al, 1993;Bowler et al, 1994a). In some circumstances activated plant cells can display repeated Ca 2ϩ spikes or oscillations (McAinsh et al, 1995) and spreading Ca 2ϩ waves (Shacklock et al, 1992;Campbell et al, 1996). Such elevations in [Ca 2ϩ ] cyt have been shown to be involved in several signaling pathways triggered, for example, by light via phytochrome (Neuhaus et al, 1993;Bowler et al, 1994aBowler et al, , 1994b, by phytohormones (Felle, 1988;Gehring et al, 1990), and even by mechanical signals and cold shock (Knight et al, 1991(Knight et al, , 1992Haley et al, 1995;Campbell et al, 1996).…”

Inositol 1,4,5-trisphosphate 3-kinases: functions and regulations

“…In plant, Ca 2+ levels are modulated by IP 3 in response to various signals including hormones, light and abiotic stresses. For example, the addition of abscisic acid (ABA) leads to increase in endogenous IP 3 levels [79]; red light elicits a rapid Ca 2+ intracellular release which can be mimicked by microinjection of IP 3 [80]; gravity stimulates a rapid increase of IP 3 in maize [81]. However, this may not be the only way for IP3K function in many biological processes.…”