User:Dcook - Revision history

Dcook at 15:36, 10 January 2006

2006-01-10T15:36:12Z

←Older revision		Revision as of 15:36, 10 January 2006
Line 45:		Line 45:
	[[media:FastVort_Arpita.avi\|Live ''Vorticella'' contracting in real time. Courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]		[[media:FastVort_Arpita.avi\|Live ''Vorticella'' contracting in real time. Courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]

-	[[~~Image~~:France_500RPM.avi~~\|thumb\|left~~\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[media:France_500RPM.avi\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[~~Image~~:France9800RPM.avi~~\|thumb\|left~~\|4.3 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[media:France9800RPM.avi\|4.3 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]

Dcook at 15:35, 10 January 2006

2006-01-10T15:35:02Z

←Older revision		Revision as of 15:35, 10 January 2006
Line 43:		Line 43:
	===Movies===		===Movies===

-	[[~~Image~~:FastVort_Arpita.avi~~\|thumb\|left~~\|Live ''Vorticella'' contracting in real time. ~~Image courtesy~~ of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]	+	[[media:FastVort_Arpita.avi\|Live ''Vorticella'' contracting in real time. Courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]

	[[Image:France_500RPM.avi\|thumb\|left\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]		[[Image:France_500RPM.avi\|thumb\|left\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

Skosuri: /* More information */ link fix

2005-12-26T19:41:06Z

More information: link fix

←Older revision		Revision as of 19:41, 26 December 2005
Line 58:		Line 58:
	==More information==		==More information==
	until further construction, see my research page: <br>		until further construction, see my research page: <br>
-	[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]	+	[http://web.mit.edu/dcook/www/research.html http://web.mit.edu/dcook/www/research.html]

Dcook at 21:18, 1 December 2005

2005-12-01T21:18:56Z

←Older revision		Revision as of 21:18, 1 December 2005
Line 52:		Line 52:
	<br style="clear:both;">		<br style="clear:both;">

-	===Original Abstract===	+	==Original Abstract==

-	'''A Centrin-based Cellular Spring that Generates nNs of Force'''	+	'''A Centrin-based Cellular Spring that Generates nNs of Force''': The spasmoneme of the unicellular protozooan Vorticella convallaria is among the fastest and most powerful cellular engines known. A contractile organelle that uses calcium instead of ATP for energy, the spasmoneme is a bundle of fibers of undetermined composition. Centrin is the major component by dry-weight and the active calcium-binding element. Also found in filamentous structures associated with various actions ranging from spindle pole and centrosome movements to contraction of whole cell bodies, centrin may be the basis of a fourth cytoskeleton. To understand how centrin-based systems are involved in cell motility, we have been characterizing the structure, mechanics, and biochemistry of the spasmoneme and report several novel findings. First, the spasmoneme is a powerful cellular engine. We imaged spontaneous contractions while imposing a centrifugal force load on the cell body. At accelerations over 10000g, the cell body becomes tear-drop shaped, its contents become stratified, and yet the stalk still contracts. We estimate an upper bound on the amount of force generated during contraction in excess of 200 nN. Second, the current rubber-band model of the spasmoneme relies on a previously observed loss of spasmoneme birefringence in the contracted state, as oriented, birefringent fibers become disoriented with added calcium. In contrast, images from the orientation-independent polarized light microscope (LCPolScope) show the spasmoneme consists of fibers that retain some degree of order in the contracted state. Finally, we are able to correlate the structure and mechanics of the spasmoneme directly with centrin. After extracting the stalks under conditions which retain reversible calcium-dependent contractility, we find that one anti-Vorticella centrin antibody (anti-centrin 5) abolishes contractility while another (anti-centrin 4) does not. These observations suggest that the spasmoneme is a centrin-based mechanism that is unlike any actin or microtubule-based cellular engine, yet more powerful.
-		+
-	~~<nowiki>~~ The spasmoneme of the unicellular protozooan Vorticella convallaria is among the fastest and most powerful cellular engines known. A contractile organelle that uses calcium instead of ATP for energy, the spasmoneme is a bundle of fibers of undetermined composition. Centrin is the major component by dry-weight and the active calcium-binding element. Also found in filamentous structures associated with various actions ranging from spindle pole and centrosome movements to contraction of whole cell bodies, centrin may be the basis of a fourth cytoskeleton. To understand how centrin-based systems are involved in cell motility, we have been characterizing the structure, mechanics, and biochemistry of the spasmoneme and report several novel findings. First, the spasmoneme is a powerful cellular engine. We imaged spontaneous contractions while imposing a centrifugal force load on the cell body. At accelerations over 10000g, the cell body becomes tear-drop shaped, its contents become stratified, and yet the stalk still contracts. We estimate an upper bound on the amount of force generated during contraction in excess of 200 nN. Second, the current rubber-band model of the spasmoneme relies on a previously observed loss of spasmoneme birefringence in the contracted state, as oriented, birefringent fibers become disoriented with added calcium. In contrast, images from the orientation-independent polarized light microscope (LCPolScope) show the spasmoneme consists of fibers that retain some degree of order in the contracted state. Finally, we are able to correlate the structure and mechanics of the spasmoneme directly with centrin. After extracting the stalks under conditions which retain reversible calcium-dependent contractility, we find that one anti-Vorticella centrin antibody (anti-centrin 5) abolishes contractility while another (anti-centrin 4) does not. These observations suggest that the spasmoneme is a centrin-based mechanism that is unlike any actin or microtubule-based cellular engine, yet more powerful.~~</nowiki>~~	+

	==More information==		==More information==
	until further construction, see my research page: <br>		until further construction, see my research page: <br>
	[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]		[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]

Dcook at 21:15, 1 December 2005

2005-12-01T21:15:49Z

←Older revision		Revision as of 21:15, 1 December 2005
Line 51:		Line 51:

	<br style="clear:both;">		<br style="clear:both;">
		+
		+	===Original Abstract===
		+
		+	'''A Centrin-based Cellular Spring that Generates nNs of Force'''
		+
		+	<nowiki> The spasmoneme of the unicellular protozooan Vorticella convallaria is among the fastest and most powerful cellular engines known. A contractile organelle that uses calcium instead of ATP for energy, the spasmoneme is a bundle of fibers of undetermined composition. Centrin is the major component by dry-weight and the active calcium-binding element. Also found in filamentous structures associated with various actions ranging from spindle pole and centrosome movements to contraction of whole cell bodies, centrin may be the basis of a fourth cytoskeleton. To understand how centrin-based systems are involved in cell motility, we have been characterizing the structure, mechanics, and biochemistry of the spasmoneme and report several novel findings. First, the spasmoneme is a powerful cellular engine. We imaged spontaneous contractions while imposing a centrifugal force load on the cell body. At accelerations over 10000g, the cell body becomes tear-drop shaped, its contents become stratified, and yet the stalk still contracts. We estimate an upper bound on the amount of force generated during contraction in excess of 200 nN. Second, the current rubber-band model of the spasmoneme relies on a previously observed loss of spasmoneme birefringence in the contracted state, as oriented, birefringent fibers become disoriented with added calcium. In contrast, images from the orientation-independent polarized light microscope (LCPolScope) show the spasmoneme consists of fibers that retain some degree of order in the contracted state. Finally, we are able to correlate the structure and mechanics of the spasmoneme directly with centrin. After extracting the stalks under conditions which retain reversible calcium-dependent contractility, we find that one anti-Vorticella centrin antibody (anti-centrin 5) abolishes contractility while another (anti-centrin 4) does not. These observations suggest that the spasmoneme is a centrin-based mechanism that is unlike any actin or microtubule-based cellular engine, yet more powerful.</nowiki>

	==More information==		==More information==
	until further construction, see my research page: <br>		until further construction, see my research page: <br>
	[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]		[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]

Dcook at 20:54, 1 December 2005

2005-12-01T20:54:54Z

←Older revision		Revision as of 20:54, 1 December 2005
Line 44:		Line 44:

	[[Image:FastVort_Arpita.avi\|thumb\|left\|Live ''Vorticella'' contracting in real time. Image courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]		[[Image:FastVort_Arpita.avi\|thumb\|left\|Live ''Vorticella'' contracting in real time. Image courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]
-	~~<br style="clear:both;">~~

	[[Image:France_500RPM.avi\|thumb\|left\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]		[[Image:France_500RPM.avi\|thumb\|left\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[Image:~~France_9800RPM~~.avi\|thumb\|left\|6 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[Image:France9800RPM.avi\|thumb\|left\|4.3 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[Image:France_9800RPM.mov\|thumb\|left\|24 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]

	<br style="clear:both;">		<br style="clear:both;">

Dcook at 20:33, 1 December 2005

2005-12-01T20:33:04Z

←Older revision		Revision as of 20:33, 1 December 2005
Line 1:		Line 1:
	{{Template:Matsudaira Lab}}		{{Template:Matsudaira Lab}}
		+	<br style="clear:both;">
	==Supporting Images for "Nano Springs Eternal"==		==Supporting Images for "Nano Springs Eternal"==
	News from the ASCB 45th Annual Meeting <br>		News from the ASCB 45th Annual Meeting <br>
Line 27:		Line 28:
	Technology,		Technology,
	Cambridge, MA		Cambridge, MA
		+
		+	<br style="clear:both;">
		+
		+	===Images===
		+
	[[Image:France_04_1201_1140_Color.jpg\|thumb\|left\|Live ''Vorticella'' visualized in the LCPolScope. Intensity encodes retardance and color encodes direction of fiber slow axis.]]		[[Image:France_04_1201_1140_Color.jpg\|thumb\|left\|Live ''Vorticella'' visualized in the LCPolScope. Intensity encodes retardance and color encodes direction of fiber slow axis.]]

Line 38:		Line 44:

	[[Image:FastVort_Arpita.avi\|thumb\|left\|Live ''Vorticella'' contracting in real time. Image courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]		[[Image:FastVort_Arpita.avi\|thumb\|left\|Live ''Vorticella'' contracting in real time. Image courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]
		+	<br style="clear:both;">
		+
		+	[[Image:France_500RPM.avi\|thumb\|left\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[Image:~~France_500RPM~~.avi\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under ~~low~~ opposing centrifugal force (~~~21g~~ acceleration) in the Centrifuge Polarization Microscope.]]	+	[[Image:France_9800RPM.avi\|thumb\|left\|6 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[Image:France_9800RPM.~~avi~~\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[Image:France_9800RPM.mov\|thumb\|left\|24 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]

	<br style="clear:both;">		<br style="clear:both;">

Dcook at 22:10, 29 November 2005

2005-11-29T22:10:50Z

←Older revision		Revision as of 22:10, 29 November 2005
Line 36:		Line 36:

	===Movies===		===Movies===
		+
		+	[[Image:FastVort_Arpita.avi\|thumb\|left\|Live ''Vorticella'' contracting in real time. Image courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]

	[[Image:France_500RPM.avi\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]		[[Image:France_500RPM.avi\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

Dcook at 22:06, 29 November 2005

2005-11-29T22:06:12Z

←Older revision		Revision as of 22:06, 29 November 2005
Line 34:		Line 34:

	<br style="clear:both;">		<br style="clear:both;">
		+
	===Movies===		===Movies===
		+
		+	[[Image:France_500RPM.avi\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]
		+
		+	[[Image:France_9800RPM.avi\|thumb\|left\|Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]
		+
		+	<br style="clear:both;">

	==More information==		==More information==
	until further construction, see my research page: <br>		until further construction, see my research page: <br>
	[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]		[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]

Dcook at 21:52, 29 November 2005

2005-11-29T21:52:52Z

←Older revision		Revision as of 21:52, 29 November 2005
Line 1:		Line 1:
	{{Template:Matsudaira Lab}}		{{Template:Matsudaira Lab}}
		+	==Supporting Images for "Nano Springs Eternal"==
		+	News from the ASCB 45th Annual Meeting <br>
		+	San Francisco, CA \| December 10-14, 2005 <br>

		+	D. C. France [1], V. Baru [2], M. Shribak [3], S. Inoue [3], S. McCutcheon[4], H. E. Buhse [4], P. T. Matsudaira [1,2,5]
		+	<br>
		+
		+	[1] Biological Engineering at the
		+	Massachusetts Institute of
		+	Technology,
		+	Cambridge, MA
		+
		+	[2] Whitehead Institute for
		+	Biomedical Research,
		+	Cambridge, MA
		+
		+	[3] Marine Biological Laboratory,
		+	Woods Hole, MA
		+
		+	[4] Biological Sciences at the
		+	University of Illinois at Chicago,
		+	Chicago, IL
		+
		+	[5] Biology at the
		+	Massachusetts Institute of
		+	Technology,
		+	Cambridge, MA
		+	[[Image:France_04_1201_1140_Color.jpg\|thumb\|left\|Live ''Vorticella'' visualized in the LCPolScope. Intensity encodes retardance and color encodes direction of fiber slow axis.]]
		+
		+	[[Image:France_extended.jpg\|thumb\|left\|Extended (in 1M EGTA) ''Vorticella'' stalk visualized in the LCPolScope.]]
		+
		+	[[Image:France_contracted.jpg\|thumb\|left\|Contracted (in 10 mM dibucaine) ''Vorticella'' stalk visualized in the LCPolScope.]]
		+
		+	<br style="clear:both;">
		+	===Movies===
		+
		+	==More information==
	until further construction, see my research page: <br>		until further construction, see my research page: <br>
	[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]		[[http://web.mit.edu/dcook/www/research.html \| http://web.mit.edu/dcook/www/research.html]]

←Older revision		Revision as of 15:36, 10 January 2006
Line 45:		Line 45:
	[[media:FastVort_Arpita.avi\|Live ''Vorticella'' contracting in real time. Courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]		[[media:FastVort_Arpita.avi\|Live ''Vorticella'' contracting in real time. Courtesy of Arpita Upadhyaya and Alexander van Oudenaarden, MIT]]

-	[[~~Image~~:France_500RPM.avi~~\|thumb\|left~~\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[media:France_500RPM.avi\|148 KB: Live ''Vorticella'' cell contracting and re-extending under low opposing centrifugal force (~21g acceleration) in the Centrifuge Polarization Microscope.]]

-	[[~~Image~~:France9800RPM.avi~~\|thumb\|left~~\|4.3 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]	+	[[media:France9800RPM.avi\|4.3 MB: Live ''Vorticella'' cell contracting and re-extending under high opposing centrifugal force (~11500g acceleration) in the Centrifuge Polarization Microscope.]]