Team:HKUSTers/Initial Proposal/Spatial Oscillator

.ideasList{ margin-bottom:30px }

ul#sub { margin:0px; padding:0px; font-size:14px; list-style-image:none; list-style-type:none;

}


 * 1) sub li { margin-bottom:20px;}

}

text-decoration:none; }
 * 1) sub li a:hover {

.links { width:100%; background-color:#1a2b8c; margin-bottom:30px; }

.links tr { background-color: dodgerblue;; }

}

.links a{	text-decoration:none; font-size:15pt; font-weight:bold; font:'helvetica'; color: white; }

.links a:active { background-color:#1a2b8c; }

}

background-color:dodgerblue; }
 * 1) navactive {

width: 100%; text-align: center; }
 * 1) header {

h4 { font-size: 14pt; font-weight: normal; }

dt { font-size: 12pt; }

padding: .4ex; }
 * 1) projectnav h4 {

font-weight: normal; margin: 1.5ex 0 0 0; }
 * 1) projectnav dt {

text-align: center; text-indent: 0; margin-left: 0; }
 * 1) projectnav h4, #projectnav dt, #projectnav dd {

background-color: dodgerblue;; border-left: dashed #FFF 3px; border-right: dashed #FFF 3px; padding: .8ex; }
 * 1) hbnav dd {

background-color: dodgerblue;; border-left: dashed #FFF 3px; border-right: dashed #FFF 3px; padding: 1ex; margin-top: 0; }
 * 1) denav dd{

color: dodgerblue; }
 * 1) projectnav a {

text-indent: 1.25em; } <! -- END of style sheet -->
 * 1) pagecontent p {

In this Spatial Oscillator, we are trying to combine chemotaxis and motility with our randomizer.

The optimal situation is that, our cells can stably maintain at one state during movement, unitl reaching to the end point, and they stop, when 1 specific AHL concentration is high enough, they regain motility and switch to another state. So the switch needs to have either bistable or automatic reversion characteristics at different stages.

References:
 * 1) UCSF 2006 : a chemotaxis receptor switch constructed
 * 2) Penn State 2006: use quorum sensing to induce motility
 * 3) Cambridge 2006: two Quorum sensing systems constructed allowing bi-directional communication

Step 1
change the original chemotaxis receptor promoter to a bistable switch, by adding inducers, oscillation can be achieved primarily

While in order for autonomous oscillation, more elements need to be added.

Step 2
autonomous-oscillation model



Although it seems that bistable switch here becomes an oscillator, what we are worried about is the bistable switch is no longer bistable. Receptor/moving direction may be uncoupled with the oscillation pattern, which means that the period for cell to move one round may not be the same length as the period for cell to oscillate 1 circle. From Cambridge 2006, we could apply 2 AHL systems to generate a bistable switch with/without autonomous oscillation.




 * 1) Whether the model can oscillate needs further simulation and testing.
 * 2) Since both LasR and LuxR repression are leaky, so that additional repression may be needed as was indicated in Penn state 2006 and Cambridge bistable switch