Noise in Synthetic Cascades - Revision history

WikiSysop at 16:03, 10 December 2007

2007-12-10T16:03:56Z

WikiSysop at 16:02, 10 December 2007

2007-12-10T16:02:36Z

Miwaters at 17:18, 6 December 2007

2007-12-06T17:18:50Z

Miwaters at 01:48, 6 December 2007

2007-12-06T01:48:09Z

Miwaters at 01:45, 6 December 2007

2007-12-06T01:45:55Z

Miwaters at 01:44, 6 December 2007

2007-12-06T01:44:00Z

Miwaters at 01:39, 6 December 2007

2007-12-06T01:39:05Z

Miwaters at 01:38, 6 December 2007

2007-12-06T01:38:49Z

Miwaters at 01:38, 6 December 2007

2007-12-06T01:38:34Z

Miwaters at 03:50, 13 November 2007

2007-11-13T03:50:42Z

@@ Line 2: / Line 2: @@
 This heterogeneity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cells follow different expression pathways (e.g. cell differentiation).
 <br><br>
-Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogeneity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' because transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)
+Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogeneity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' because transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins ''et. al.'', 2005)

@@ Line 1: / Line 1: @@
 HH McAdams and A Arkin characterized noise propagation in synthetic cascades. They detailed that stochasticity in gene cascades results from time delay in protein accumulation. More specifically, after the activation of a gene, to reach an effective level of control over the next gene requires time for protein signals (inducers and repressors) to accumulate. A threshold of protein control must be achieved in order for the successive protein to propagate its signal to the subsequent gene. Because proteins are produced in short bursts of variable numbers at random time intervals, there can be large discrepancies in the time between successive events in a regulatory cascade across a cell population (McAdams & Arkin, 1997).
-This heterogeneity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways (e.g. cell differentiation).
+This heterogeneity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cells follow different expression pathways (e.g. cell differentiation).
 <br><br>
 Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogeneity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' because transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)

@@ Line 1: / Line 1: @@
-HH McAdams and A Arkin characterized noise propagation in synthetic cascades. They detailed that stochasticity in gene cascades lies in the time delay for protein accumulation. More specifically, after the activation of a gene, to reach an effective level of control over the next gene requires a time for protein signals (inducers and repressors) to acumulate. A threshold of protein control must be achieved in order for the sucessive protein to propagate its signal to the subsequent gene. Becuase proteins are produced in short bursts of variable numbers at random time intervals, there can be large discrepancies in the time between sucessive events in a regulatory cascade across a cell population (McAdams & Arkin, 1997).
+HH McAdams and A Arkin characterized noise propagation in synthetic cascades. They detailed that stochasticity in gene cascades results from time delay in protein accumulation. More specifically, after the activation of a gene, to reach an effective level of control over the next gene requires time for protein signals (inducers and repressors) to accumulate. A threshold of protein control must be achieved in order for the successive protein to propagate its signal to the subsequent gene. Because proteins are produced in short bursts of variable numbers at random time intervals, there can be large discrepancies in the time between successive events in a regulatory cascade across a cell population (McAdams & Arkin, 1997).
-This heterogenity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways (e.g. cell differentiation).
+This heterogeneity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways (e.g. cell differentiation).
 <br><br>
-Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogenity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' becuase transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)
+Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogeneity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' because transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)
 <center>

@@ Line 1: / Line 1: @@
 HH McAdams and A Arkin characterized noise propagation in synthetic cascades. They detailed that stochasticity in gene cascades lies in the time delay for protein accumulation. More specifically, after the activation of a gene, to reach an effective level of control over the next gene requires a time for protein signals (inducers and repressors) to acumulate. A threshold of protein control must be achieved in order for the sucessive protein to propagate its signal to the subsequent gene. Becuase proteins are produced in short bursts of variable numbers at random time intervals, there can be large discrepancies in the time between sucessive events in a regulatory cascade across a cell population (McAdams & Arkin, 1997).
-This heterogenity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways.
+This heterogenity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways (e.g. cell differentiation).
 <br><br>
 Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogenity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' becuase transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)

@@ Line 2: / Line 2: @@
 This heterogenity of protein expression among genetic cascades can result in a separation of the cell population into different phenotypes as the cell follow different expression pathways.
 <br><br>
-Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in transcriptional regulatory signal increased population heterogenity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that this fit his hypothesis becuase transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)
+Collins expressed that his colleague WJ Blake had engineered a transcriptional cascade composed of two regulatory steps. He found that increased noise in the transcriptional regulatory signal increased population heterogenity very little at high or low levels of induction and was most sensitive during intermediate levels of induction. He commented that these data made sense ''in silico'' becuase transcription rate is most sensitive to variation in regulatory signal at intermediate levels. The figure below illustrates this point as reporter abundance curve has the highest slope at intermediate levels of induction. (Collins et. al., 2005)
 <center>

@@ Line 7: / Line 7: @@
 Figure 1<br>
-[[Image:Reporterabundacne.png |300 px]]</center>
+[[Image:Reporterabundacne.png |300 px]]
 <br>
 Figure 1 was obtained at http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&uid=15883588&cmd=showdetailview&indexed=google permission pending
-<br><br>
+<br><br></center>
 Figure 1 details protein abundance in response to an inducing signal
 <br><br><br>
 <center><b> [[Noise in Feedback Loops | Next Section in Manipulation of Stochasticity]] | [[Manipulation of Stochasticity | Return to Manipulation of Stochasticity]] </b></center>