CH391L/S13/Optogenetics - Revision history

Siddharth Das: /* Gene Delivery */

Siddharth Das — Thu, 25 Apr 2013 12:13:58 GMT

Gene Delivery

←Older revision		Revision as of 12:13, 25 April 2013
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	Opsin genes are transported into the target cells by transfection, viral transduction or transgenic animal lines. Although the viral delivery system isn’t cell type specific, the included promoter ensures expression only in the desired cells. In other words, the virus infects plethora of cell types, but the desired cells express the distinct promoter regions not shared by other neurons. Both lentivirus and adeno-associated virus vectors are used to transfer optogenetic circuitry into the desired cell type. Basically, the virus is loaded up with the promoter associated with the desired neuron and injected via stereotaxic needle closest to the desired region. Both lentivirus and AAV vectors induce long-term expression. However, lentivirus delivery are permanently integrated into the genome, while the AAV vectors are maintained extra-chromosomally. Even though virus delivery systems provide cell specific selection, the virus, themselves, have a limited packaging capacity. The lenitivirus can accomadate up to 10 kb while the AAV can include up to 5 kb. In response, transgenic animals can allow for bigger promoters to be used for increased specificity and increased expression<cite>Mei2012</cite>.		Opsin genes are transported into the target cells by transfection, viral transduction or transgenic animal lines. Although the viral delivery system isn’t cell type specific, the included promoter ensures expression only in the desired cells. In other words, the virus infects plethora of cell types, but the desired cells express the distinct promoter regions not shared by other neurons. Both lentivirus and adeno-associated virus vectors are used to transfer optogenetic circuitry into the desired cell type. Basically, the virus is loaded up with the promoter associated with the desired neuron and injected via stereotaxic needle closest to the desired region. Both lentivirus and AAV vectors induce long-term expression. However, lentivirus delivery are permanently integrated into the genome, while the AAV vectors are maintained extra-chromosomally. Even though virus delivery systems provide cell specific selection, the virus, themselves, have a limited packaging capacity. The lenitivirus can accomadate up to 10 kb while the AAV can include up to 5 kb. In response, transgenic animals can allow for bigger promoters to be used for increased specificity and increased expression<cite>Mei2012</cite>.

-	[[[Image:Lentivirus.png\|thumb\|right\|''lentivirus'' vector used in neural modulation<cite>SyntheticNeurobiology2010</cite>.]]	+	[[Image:Lentivirus.png\|thumb\|right\|''lentivirus'' vector used in neural modulation<cite>SyntheticNeurobiology2010</cite>.]]

	===Controlled Illumination===		===Controlled Illumination===

Siddharth Das at 12:13, 25 April 2013

Siddharth Das — Thu, 25 Apr 2013 12:13:29 GMT

←Older revision		Revision as of 12:13, 25 April 2013
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	===Gene Delivery===		===Gene Delivery===
-	[[Image:AAV.png\|thumb\|right]]	+
-	Opsin genes are transported into the target cells by transfection, viral transduction or transgenic animal lines. Although the viral delivery system isn’t cell type specific, the included promoter ensures expression only in the desired cells. In other words, the virus infects plethora of cell types, but the desired cells express the distinct promoter regions not shared by other neurons. Both lentivirus and adeno-associated virus vectors are used to transfer optogenetic circuitry into the desired cell type. Basically, the virus is loaded up with the promoter associated with the desired neuron and injected via stereotaxic needle closest to the desired region. Both lentivirus and AAV vectors induce long-term expression. However, lentivirus delivery are permanently integrated into the genome, while the AAV vectors are maintained extra-chromosomally. Even though virus delivery systems provide cell specific selection, the virus, themselves, have a limited packaging capacity. The lenitivirus can accomadate up to 10 kb while the AAV can include up to 5 kb. In response, transgenic animals can allow for bigger promoters to be used for increased specificity and increased expression. <cite>Mei2012</cite>	+	[[Image:AAV.png\|thumb\|right\|''Dependovirus adeno-associated virus'' vector used in neural modulation<cite>SyntheticNeurobiology2010</cite>.]]
-	[[Image:Lentivirus.png\|thumb\|right]]	+
		+	Opsin genes are transported into the target cells by transfection, viral transduction or transgenic animal lines. Although the viral delivery system isn’t cell type specific, the included promoter ensures expression only in the desired cells. In other words, the virus infects plethora of cell types, but the desired cells express the distinct promoter regions not shared by other neurons. Both lentivirus and adeno-associated virus vectors are used to transfer optogenetic circuitry into the desired cell type. Basically, the virus is loaded up with the promoter associated with the desired neuron and injected via stereotaxic needle closest to the desired region. Both lentivirus and AAV vectors induce long-term expression. However, lentivirus delivery are permanently integrated into the genome, while the AAV vectors are maintained extra-chromosomally. Even though virus delivery systems provide cell specific selection, the virus, themselves, have a limited packaging capacity. The lenitivirus can accomadate up to 10 kb while the AAV can include up to 5 kb. In response, transgenic animals can allow for bigger promoters to be used for increased specificity and increased expression<cite>Mei2012</cite>.
		+
		+	[[[Image:Lentivirus.png\|thumb\|right\|''lentivirus'' vector used in neural modulation<cite>SyntheticNeurobiology2010</cite>.]]

	===Controlled Illumination===		===Controlled Illumination===
-	~~[[Image:CH391L_S13_Your_Illumination.png.jpg\|thumb\|right]]~~

-	The basis of optogenetics is to use light to elicit a physiological response within the cell. This entails the uses of technologies that can illuminate transformed regions. In brief, these technologies include, LED, one-photon laser, optical fibers, and optrodes. <cite>Mei2012</cite>	+	The basis of optogenetics is to use light to elicit a physiological response within the cell. This entails the uses of technologies that can illuminate transformed regions. In brief, these technologies include, LED, one-photon laser, optical fibers, and optrodes<cite>Mei2012</cite>.

	===Record===		===Record===
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	===Neuroscience===		===Neuroscience===
-	Obviously, optogenetics has huge applications in the field of neuroscience. Indeed, the ability excite and silence cells in order to ascertain the functional units of studied neural circuits are unparalleled, but the ultimate goal is to construct robust therapeutic technologies. For the example, parvalbumin, dopamingernic, and orexinergic neurons are affected by schizophrenia, Parkinson's disease, and narcolepsy, respectively. Deep brain stimulation is ineffective for such diseases, because the true onset of each disease is still unknown; random stimulation proves to be futile. ~~Optogenetic~~ research aims to ~~discover in detail each~~ of ~~these~~ neural diseases. <cite>Lalumiere2011</cite>	+	Obviously, optogenetics has huge applications in the field of neuroscience. Indeed, the ability excite and silence cells in order to ascertain the functional units of studied neural circuits are unparalleled, but the ultimate goal is to construct robust therapeutic technologies. For the example, parvalbumin, dopamingernic, and orexinergic neurons are affected by schizophrenia, Parkinson's disease, and narcolepsy, respectively. Deep brain stimulation is ineffective for such diseases, because the true onset of each disease is still unknown; random stimulation proves to be futile. In this respect, optogenetic research aims to further our understanding of neural diseases<cite>Lalumiere2011</cite>.

-	For example, epilepsy is a brain disorder in which the person has multiple seizures due to hyperactivity of certain cortical regions. Treatment for epilepsy is quite limited; current drugs and therapies do not properly treat or prevent the convulsions. Now, optogenetic research aims to target those hyperactive neurons and insert eNpHR3.0 opsin gene into the cells. In turn, the shining of yellow light would perturb the hyperactive neurons, effectively silencing them during an epileptic attack. This technology is analogous to an inhaler "silencing" an asthma attack. <cite>Kokaia2012</cite>	+	For example, epilepsy is a brain disorder in which the person has multiple seizures due to hyperactivity of certain cortical regions. Treatment for epilepsy is quite limited; current drugs and therapies do not properly treat or prevent the convulsions. Now, optogenetic research aims to target those hyperactive neurons and insert eNpHR3.0 opsin gene into the cells. In turn, the shining of yellow light would perturb the hyperactive neurons, effectively silencing them during an epileptic attack. This technology is analogous to an inhaler "silencing" an asthma attack<cite>Kokaia2012</cite>.

	Chimeric proteins, known as OptoXRs, composed of bovine rhodopsin and the G protein–coupled receptors allow optical control of biochemical mediated cascades.		Chimeric proteins, known as OptoXRs, composed of bovine rhodopsin and the G protein–coupled receptors allow optical control of biochemical mediated cascades.

-	Recently, by using optogentic tools, scientist have restored vision to blinded mice, by splicing ChR2 protein into the retina of the mice. Through rAAV, the opsin genes were transformed into ON bipolar cells. <cite>Doroudchi2011</cite>	+	Recently, by using optogentic tools, scientist have restored vision to blinded mice, by splicing ChR2 protein into the retina of the mice. Through rAAV, the opsin genes were transformed into ON bipolar cells<cite>Doroudchi2011</cite>.

	===IGEM Take-home Message===		===IGEM Take-home Message===
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	==Other Light Sensors==		==Other Light Sensors==
-	Light responsive proteins or "light sensors" are currently used as an method of signal transduction in order to regulate genetic circuits non-invasively within organisms. Light sensor proteins are found in all domains of life and have been utilized in complex genetic regulation to willfully turn off or on a gene of interest. Incidentally, the light sensor protein is a transmembrane channel or receptor found directly on the surface of most organisms. Particularly, the the majority of these light sensors consist of photoreceptors. In brief, a photon hits the photoreceptor and initiates a conformational change leading to possible phosphorylation by kinase or delocalization of trascription factor. Subsequently, this creates a biochemical signalling cascade that induces a molecular mediatory molecule to interact with the following regulatory molecules or simply interact with the gene complex. Photoreceptors are multidomain effector proteins that contain the protein component, pigment, and the chromophore. The ~~the~~ pigment acts as a antennae station to attract photons. Photon acquirement lead to a change in the aromatic structure of chromophore which initiates the comforational change. By creating chimeras and other fusion proteins, an individual can easily take advantage of an promoter/ regulatory molecule to build new cascades thereby affecting different genetic ciruits.<cite>Levskaya2005</cite>	+	Light responsive proteins or "light sensors" are currently used as an method of signal transduction in order to regulate genetic circuits non-invasively within organisms. Light sensor proteins are found in all domains of life and have been utilized in complex genetic regulation to willfully turn off or on a gene of interest. Incidentally, the light sensor protein is a transmembrane channel or receptor found directly on the surface of most organisms. Particularly, the the majority of these light sensors consist of photoreceptors. In brief, a photon hits the photoreceptor and initiates a conformational change leading to possible phosphorylation by kinase or delocalization of trascription factor. Subsequently, this creates a biochemical signalling cascade that induces a molecular mediatory molecule to interact with the following regulatory molecules or simply interact with the gene complex. Photoreceptors are multidomain effector proteins that contain the protein component, pigment, and the chromophore. The pigment acts as a antennae station to attract photons. Photon acquirement lead to a change in the aromatic structure of chromophore which initiates the comforational change. By creating chimeras and other fusion proteins, an individual can easily take advantage of an promoter/ regulatory molecule to build new cascades thereby affecting different genetic ciruits<cite>Levskaya2005</cite>.

	===Types of Photoreceptors===		===Types of Photoreceptors===
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	#Mei2012 pmid=22480664		#Mei2012 pmid=22480664
	#Pastrana2010 [http://www.nature.com/nmeth/journal/v8/n1/full/nmeth.f.323.html Optogenetics: controlling cell function with light]		#Pastrana2010 [http://www.nature.com/nmeth/journal/v8/n1/full/nmeth.f.323.html Optogenetics: controlling cell function with light]
		+	#SyntheticNeurobiology2010 [http://syntheticneurobiology.org/protocols/protocoldetail/32/10 ChR2: Channelrhodopsin-2 from C. reinhardtii: genetically-encoded reagent for blue-light neural activation]
	#VanderHorst2004 pmid=14730990		#VanderHorst2004 pmid=14730990
	#Yizhar2011 pmid=21363959		#Yizhar2011 pmid=21363959
	#Zemelman2002 pmid=11779476		#Zemelman2002 pmid=11779476
	</biblio>		</biblio>

Siddharth Das: /* Introduction to Optogenetics */

Siddharth Das — Thu, 25 Apr 2013 11:45:05 GMT

Introduction to Optogenetics

Show changes

Siddharth Das at 11:00, 25 April 2013

Siddharth Das — Thu, 25 Apr 2013 11:00:48 GMT

←Older revision		Revision as of 11:00, 25 April 2013
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	{\| cellpadding="4"		{\| cellpadding="4"
-	\|- bgcolor="~~lightgray~~"	+	\|- bgcolor="lightblue"
	! Year !! Event		! Year !! Event
	\|-		\|-

Siddharth Das at 11:00, 25 April 2013

Siddharth Das — Thu, 25 Apr 2013 11:00:23 GMT

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	[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|frame\|right\|Common optogenetic tools for inducing depolarizing and hyperpolarizing events <cite>Pastrana2010</cite>]]		[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|frame\|right\|Common optogenetic tools for inducing depolarizing and hyperpolarizing events <cite>Pastrana2010</cite>]]

-	~~In essence,~~ optogenetics is a ~~neural modulation technique used to control neurons ''in vitro'' for the purpose~~ of ~~affecting the physiology of neural circuits and ultimately behavior of the studied organism. However,~~ in ~~recent studies, optogenetic techniques have been used to modify nonneuronal tissues,~~ such as ~~cardiac tissue and beta cells~~, ~~willfully controlling the respective cell-specific roles~~. ~~Although~~ the ~~implications of~~ optogenetics ~~seem like a panacea for many genetic diseases, much of~~ the field ~~is new; in terms~~ of ~~therapeutics~~, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the ~~synergy between neuroscience and synthetic biology~~. ~~Current optogenetically-related research aims to ascertain brain function~~ of ~~multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases~~ and ~~neuroprosthetics~~.	+	The umbrage of optogenetics encompasses a plethora of techniques in which a light sensitive membrane protein elicits a biochemical event such as transcription, kinase activity or even ion transfer. Today, the term "optogenetics" tends to be associated with the field of neuroscience, where arguably optogenetics proves to be the most utilitarian. Optogenetics takes advantage of a wide array of opsins and photoreceptors, both delineating into distinctive proteins with special characteristics.

-	~~The basis is optogentics is quite simple.~~ The neuron in question is spliced with a specific opsin gene carried by viral vector, usually a modified lentivirus. Subsequently, the encoded opsin attached to the cell membrane. Opsin are photosensitive G protein receptors or ion channels that are induced by a specific wavelength of visible light via fiber optic cable or optrode. In turn, the opsin undergoes a conformational change, eliciting a change in membrane potential. For neuronal cells, changes in membrane potential give rise to action potentials. The strength of the depolarizing current (incoming positive charged ions) is encoded in the frequency of the action potentials generated. Furthermore, synapses (gap junction between neurons) can conduct spatial or temporal summation. Even neuronal cells can be silenced with hyperpolarizing current (incoming negative or outgoing positive charged ions). In short, optogenetics provides neuroscientists with an “on/off” switch for targeted neurons.	+	In brief, The neuron in question is spliced with a specific opsin gene carried by viral vector, usually a modified lentivirus. Subsequently, the encoded opsin attached to the cell membrane. Opsin are photosensitive G protein receptors or ion channels that are induced by a specific wavelength of visible light via fiber optic cable or optrode. In turn, the opsin undergoes a conformational change, eliciting a change in membrane potential. For neuronal cells, changes in membrane potential give rise to action potentials. The strength of the depolarizing current (incoming positive charged ions) is encoded in the frequency of the action potentials generated. Furthermore, synapses (gap junction between neurons) can conduct spatial or temporal summation. Even neuronal cells can be silenced with hyperpolarizing current (incoming negative or outgoing positive charged ions). In short, optogenetics provides neuroscientists with an “on/off” switch for targeted neurons.
		+
		+	In essence, optogenetics is a neural modulation technique used to control neurons ''in vitro'' for the purpose of affecting the physiology of neural circuits and ultimately behavior of the studied organism. However, in recent studies, optogenetic techniques have been used to modify nonneuronal tissues, such as cardiac tissue and beta cells, willfully controlling the respective cell-specific roles. Although the implications of optogenetics seem like a panacea for many genetic diseases, much of the field is new; in terms of therapeutics, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the synergy between neuroscience and synthetic biology. Current optogenetically-related research aims to ascertain brain function of multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases and neuroprosthetics.

	==History==		==History==

Siddharth Das at 10:41, 25 April 2013

Siddharth Das — Thu, 25 Apr 2013 10:41:08 GMT

←Older revision		Revision as of 10:41, 25 April 2013
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	</blockquote>		</blockquote>

-	[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|right\|Common optogenetic tools for inducing depolarizing and hyperpolarizing events <cite>Pastrana2010</cite>]]	+	[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|frame\|right\|Common optogenetic tools for inducing depolarizing and hyperpolarizing events <cite>Pastrana2010</cite>]]

	In essence, optogenetics is a neural modulation technique used to control neurons ''in vitro'' for the purpose of affecting the physiology of neural circuits and ultimately behavior of the studied organism. However, in recent studies, optogenetic techniques have been used to modify nonneuronal tissues, such as cardiac tissue and beta cells, willfully controlling the respective cell-specific roles. Although the implications of optogenetics seem like a panacea for many genetic diseases, much of the field is new; in terms of therapeutics, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the synergy between neuroscience and synthetic biology. Current optogenetically-related research aims to ascertain brain function of multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases and neuroprosthetics.		In essence, optogenetics is a neural modulation technique used to control neurons ''in vitro'' for the purpose of affecting the physiology of neural circuits and ultimately behavior of the studied organism. However, in recent studies, optogenetic techniques have been used to modify nonneuronal tissues, such as cardiac tissue and beta cells, willfully controlling the respective cell-specific roles. Although the implications of optogenetics seem like a panacea for many genetic diseases, much of the field is new; in terms of therapeutics, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the synergy between neuroscience and synthetic biology. Current optogenetically-related research aims to ascertain brain function of multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases and neuroprosthetics.

Siddharth Das at 10:37, 25 April 2013

Siddharth Das — Thu, 25 Apr 2013 10:37:38 GMT

←Older revision		Revision as of 10:37, 25 April 2013
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	</blockquote>		</blockquote>

-	[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|right]]	+	[[Image:CH391L_S13_Your_Action_Potential.png.jpg‎\|right\|Common optogenetic tools for inducing depolarizing and hyperpolarizing events <cite>Pastrana2010</cite>]]

	In essence, optogenetics is a neural modulation technique used to control neurons ''in vitro'' for the purpose of affecting the physiology of neural circuits and ultimately behavior of the studied organism. However, in recent studies, optogenetic techniques have been used to modify nonneuronal tissues, such as cardiac tissue and beta cells, willfully controlling the respective cell-specific roles. Although the implications of optogenetics seem like a panacea for many genetic diseases, much of the field is new; in terms of therapeutics, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the synergy between neuroscience and synthetic biology. Current optogenetically-related research aims to ascertain brain function of multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases and neuroprosthetics.		In essence, optogenetics is a neural modulation technique used to control neurons ''in vitro'' for the purpose of affecting the physiology of neural circuits and ultimately behavior of the studied organism. However, in recent studies, optogenetic techniques have been used to modify nonneuronal tissues, such as cardiac tissue and beta cells, willfully controlling the respective cell-specific roles. Although the implications of optogenetics seem like a panacea for many genetic diseases, much of the field is new; in terms of therapeutics, research is regretfully far behind. Currently, optogenetic techniques are attempted mostly on rodent specimens since primate studies lack profound electrophysical and behavior effects. Optogenetic is widely associated with neuroscience research- sometimes thought as the synergy between neuroscience and synthetic biology. Current optogenetically-related research aims to ascertain brain function of multiple neural circuits, but future endeavors include gene therapy for neurodegenerative diseases and neuroprosthetics.
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	#Levskaya2005 pmid=16306980		#Levskaya2005 pmid=16306980
	#Mei2012 pmid=22480664		#Mei2012 pmid=22480664
		+	#Pastrana2010 [http://www.nature.com/nmeth/journal/v8/n1/full/nmeth.f.323.html Optogenetics: controlling cell function with light]
	#VanderHorst2004 pmid=14730990		#VanderHorst2004 pmid=14730990
	#Yizhar2011 pmid=21363959		#Yizhar2011 pmid=21363959
	#Zemelman2002 pmid=11779476		#Zemelman2002 pmid=11779476
	</biblio>		</biblio>

Siddharth Das: /* Biochemistry behind Optogenetics */

Siddharth Das — Mon, 04 Mar 2013 19:59:18 GMT

Biochemistry behind Optogenetics

←Older revision		Revision as of 19:59, 4 March 2013
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	BR process:		BR process:
	# Photon absorption initiates isomerization of bounded retinal from all-trans to 13-cis		# Photon absorption initiates isomerization of bounded retinal from all-trans to 13-cis
-	# confirmation shift and dipole of RSHB+ raises pK, releasing RSB proton and created M intermediate (410nm maximum absorbance)	+	# confirmation shift and dipole of RSHB+ raises pK, releasing RSB proton (deprotonated retinal Schiff base) and created M intermediate (410nm maximum absorbance)
	# Release RSB proton is accepted by the Asp 85		# Release RSB proton is accepted by the Asp 85
-	# Simultaneously, a different proton is released from an amino acid group from the proton release complex	+	# Simultaneously, a different proton is released from an amino acid group from the proton release complex (PRC)
	# RSB captures proton from Asp 96 and the protein enters the N intermediate (560 nm)		# RSB captures proton from Asp 96 and the protein enters the N intermediate (560 nm)
	# Asp 96 is repronated by cytoplasmic protons while the Schiff bases reisomerizes into all-trans retinal (630nm)		# Asp 96 is repronated by cytoplasmic protons while the Schiff bases reisomerizes into all-trans retinal (630nm)
	# Asp 85 transfers its proton to the PRC		# Asp 85 transfers its proton to the PRC

-	In the case of halorhodopsin (HR), the photocycle does not include the depronation of RSBH+. After light induction, the proton cannot be releases because the acceptor amino acid normally found is BR has been replaced by ~~Thr~~. Instead, a chloride ion is moved from through the chromophore and then sifted through the protein. Since activation of HR is meek, addition mammalian membrane trafficking signals provide robust expression of inhibition. HR is activated by yellow light.	+	In the case of halorhodopsin (HR), the photocycle does not include the depronation of RSBH+. After light induction, the proton cannot be releases because the acceptor amino acid normally found is BR has been replaced by Threonine. Instead, a chloride ion is moved from through the chromophore and then sifted through the protein. Since activation of HR is meek, addition mammalian membrane trafficking signals provide robust expression of inhibition. HR is activated by yellow light.

	Sensory rhodopsin (SR-I) and phoborhodopsin (SR-II) are similar to BR except the opsin activates secondary messager Htr to activate an associated phosphorylation cascade.		Sensory rhodopsin (SR-I) and phoborhodopsin (SR-II) are similar to BR except the opsin activates secondary messager Htr to activate an associated phosphorylation cascade.

Siddharth Das: /* History */

Siddharth Das — Mon, 04 Mar 2013 19:51:09 GMT

History

←Older revision		Revision as of 19:51, 4 March 2013
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	\| 1971 \|\| Bacteriorhodopsin (yellow and green) found in Halobacterium halobium		\| 1971 \|\| Bacteriorhodopsin (yellow and green) found in Halobacterium halobium
	\|-		\|-
-	\| 1977 \|\| Halorhodopsin (yellow)	+	\| 1977 \|\| Halorhodopsin (yellow) found in Halobacterium halobium
	\|-		\|-
	\| 1999 \|\| Francis Crick's Declaration		\| 1999 \|\| Francis Crick's Declaration
	\|-		\|-
-	\| 2002 \|\| ChR1 (blue), Zemelman and Miesenbock chARGed optogenetic system <cite>Zemelman2002</cite>	+	\| 2002 \|\| ChR1 (blue) discovered in Chlamydomonas reinhardtii, Zemelman and Miesenbock chARGed optogenetic system <cite>Zemelman2002</cite>
	\|-		\|-
-	\| 2003 \|\| ChR2 (blue)	+	\| 2003 \|\| ChR2 (blue) discovered in Chlamydomonas reinhardtii
	\|-		\|-
	\| 2005 \|\| Millisecond-timescale, genetically targeted optical control of neural activity <cite>Boyden2005</cite>		\| 2005 \|\| Millisecond-timescale, genetically targeted optical control of neural activity <cite>Boyden2005</cite>
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	\| 2006 \|\| "Optogenetics" coined		\| 2006 \|\| "Optogenetics" coined
	\|-		\|-
-	\| 2008 \|\| VChR1 (yellow and possibly green)	+	\| 2008 \|\| VChR1 found in Volvox carteri (yellow and possibly green)
	\|}		\|}

Siddharth Das: /* IGEM Take-home Message */

Siddharth Das — Mon, 04 Mar 2013 15:56:46 GMT

IGEM Take-home Message

←Older revision		Revision as of 15:56, 4 March 2013
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	===IGEM Take-home Message===		===IGEM Take-home Message===
	The 2012 IGEM team from the University of Washington conducted a project under optogenetics. The team's main focus was to effectively characterize the light sensor gene systems: Ccas and lavTAP. Both gene systems were combined with a lacZ system in order to determine the activity of the light sensor's autophosphorylation process. For the Ccas, green light stimulated autophosphorylation and expression of lacZ, while red light stimulates a conformational change that resists autophosphorylation and thus don't all binding to the promoter of the the lacZ. The lavTAP system is combined with an inverter gene so that blue light stimulates expression of the lacZ, analogous to repression regulation. In the future, the use of light sensors would benefit synthetic biologists by creating light sensor/ protein fusions to mediated specific biochemical cascades.		The 2012 IGEM team from the University of Washington conducted a project under optogenetics. The team's main focus was to effectively characterize the light sensor gene systems: Ccas and lavTAP. Both gene systems were combined with a lacZ system in order to determine the activity of the light sensor's autophosphorylation process. For the Ccas, green light stimulated autophosphorylation and expression of lacZ, while red light stimulates a conformational change that resists autophosphorylation and thus don't all binding to the promoter of the the lacZ. The lavTAP system is combined with an inverter gene so that blue light stimulates expression of the lacZ, analogous to repression regulation. In the future, the use of light sensors would benefit synthetic biologists by creating light sensor/ protein fusions to mediated specific biochemical cascades.
-	http://~~www.~~2012.igem.org/Team:Washington/Optogenetics~~#Background~~	+	[http://2012.igem.org/Team:Washington/Optogenetics]

	==Other Light Sensors==		==Other Light Sensors==