IGEM:Harvard/2006/DNA nanostructures: Difference between revisions

From OpenWetWare
Jump to navigationJump to search
mNo edit summary
 
(83 intermediate revisions by 7 users not shown)
Line 1: Line 1:
==Why THIS Antithrombotic?==
<div class="tabs-blue">
'''How is this better than existing antithrombotics (heparin, warfarin, and thrombolitics)?'''
<ul>
<li id="current">[[IGEM:Harvard/2006/DNA nanostructures|Project Overview]]</li>
<li>[[IGEM:Harvard/2006/DNA_nanostructures/Designs|Designs]]</li>
<li>[[IGEM:Harvard/2006/DNA_nanostructures/Notebook|Notebook]]</li>
<li>[[IGEM:Harvard/2006/DNA_nanostructures/Protocols|Protocols]]</li>
<li>[[IGEM:Harvard/2006/DNA_nanostructures/Presentations|Presentations]]</li>
<li>[[IGEM:Harvard/2006/DNA_nanostructures/Literature|Literature]]</li>
</ul>
</div>
<br style="clear:both">


*'''Heparin:''' may induce immunological thrombocytopenia (we don't know if ours will or not), tends to bind to plasma proteins (ours won't - see PMID: 8107090 below).


*'''Warfarin (Coumadin):''' small therapeutic window (ours will work molarly, thus we'll have to worry about not having ENOUGH, rather than having too much, once "we" (ie. pharmaceuticals) get a baseline curve in the human), and thus constant clinical supervision (the oligo keys will clear so fast, it shouldn't be a problem).
==Project Overview==
*Our goal is to design and implement molecular containers, which can be dynamically opened and closed by an external stimulus.
*The containers will be implemented as DNA nanostructures, which afford a significant degree of positional control and chemical versatility.
*As an initial proof-of-concept, we plan to use our DNA containers to demonstrate controllable activation ("delivery") of anti-thrombin aptamers.
*We expect that molecular containers could have several interesting scientific and clinical applications, such as
**Drug and gene delivery
**Bio-marker scavenging (early detection of biomarkers)
**Directed evolution (compartmentalized selections)
**Using multiplexing for combinatorial chemical synthesis
**Capture and stabilization of multiprotein complexes
**Protein folding (chaperones)
**Cell sorting


*'''Both:''' food and drug interactions (ours probably won't - aptamer has been tested against some other control proteins, and it doesn't bind them much - again, see PMID: 8107090)
==Working Team Members==
*[[User:TChan|Tiffany Chan]] ([[User_talk:TChan|talk]], [[Special:Contributions/TChan|edits]])
*[[User:Kfifer|Katherine Fifer]] ([[User_talk:Kfifer|talk]], [[Special:Contributions/Kfifer|edits]])
*[[User:Vlau|Valerie Lau]] ([[User_talk:Vlau|talk]], [[Special:Contributions/Vlau|edits]])
*[[User:Matthewmeisel|Matthew Meisel]] ([[User_talk:Matthewmeisel|talk]], [[Special:Contributions/Matthewmeisel|edits]])
*[[User:Lhahn|Lewis Hahn]] ([[User_talk:Lhahn|talk]], [[Special:Contributions/Lhahn|edits]])
*TA: [[User:ShawnDouglas|Shawn Douglas]] ([[User_talk:ShawnDouglas|talk]], [[Special:Contributions/ShawnDouglas|edits]])


All of this info is from:
==Recent Changes==
 
{{Special:Recentchanges/b=IGEM:Harvard/2006/DNA_nanostructures/&limit=20}}
<biblio>
anti1 pmid=16218489
</biblio>
 
 
'''Why not just naked aptamers?'''
*clearance too quick, but ours will be hidden until the box is opened - hopefully it'll bind fast enough to not make its easy clearance a problem
 
*"Thrombin is the most obvious target for the generation of both anticoagulant and antithrombotic compounds. Bock et al. (19) generated a 15 nucleotide DNA-based thrombin aptamer that binds thrombin with moderate affinity (apparent Kd ~10–7 M) and can prolong the clotting time of human plasma. To take advantage of its rapid clearance (in vivo half-life of approximately 1–2 minutes), the thrombin DNA aptamer was developed largely as an anticoagulant for use in surgical indications requiring regional anticoagulation of an extracorporeal circuit. When administered by constant infusion, this molecule was successfully used to maintain the patency of an extracorporeal circuit in sheep and was substituted for heparin in a canine cardiopulmonary bypass model (20, 21). Furthermore, because of its rapid clearance, once infusion of the aptamer was stopped, no reversal of the anticoagulant activity of this molecule was required. Based on its ability to inhibit clot-bound thrombin and platelet thrombus formation in an ex vivo whole artery angioplasty model, this aptamer also exhibited potential as a novel antithrombotic (22). However, for this thrombin aptamer to be successfully tested in animal models of arterial thrombosis, it would probably be necessary to modify it to improve its circulating half-life." --- White et al., 2000
 
<biblio>
napt1 pmid=11032851
</biblio>
 
 
==Roadblocks and Solutions==
#Big Concept
#*Is this really better than currently available antithrombins?
#**Not in efficacy, necessarily.  But it's more generalizable, engineerable, and whether or not the triggerability and the bioavailability features work in our favor is something drug companies spend years testing.  In essence, the thrombin problem is just an example application of the greater idea of a triggerable drug box - it is our proof of concept.
 
#Nitty-Gritty Details
#*How is this going to stay in the body?
#**The "lock," or the box structure, will be covered in a non-immunologic polymer, such as PEG (REFERENCE) or PLGA (REFERENCE), allowing it to traverse the bloodstream, or perhaps eventually enter the cell (REFERENCE) and drop cargo.  <br>Part of the functionality of the "key," or the oligo clasp-opening strand, is that it will be quickly cleared if it does not bind the lock within the time that naked DNA is cleared, approximately 5-10 minutes.  This allows a quick pulse-controlled attack against thrombin, though the possibility of a constant stream of key time-released or released by IV is not impossible.  <br>And the opened structures will be cleared, thrombin attached, thus permanently and immediately lowering the levels of that protein from the blood.
 
#*How big is this stuff going to be anyway?  And how much thrombin will it bind?
#**The thrombin-aptamer is approximately 3nm long, 2nm wide.  If the open-faced tetrahedron is used, it could be designed to be big enough to just fit one aptamer within, or four aptamers, one on each side.  The limiting factor here is the need to keep the aptamer within the confines of the structure.  However, my personal preference is for a closed-face structure because, w/ an open-faced one which needs to be constrained based on geometry, the odds of difficulty folding are higher. 
 
#*Is there a chance that the aptamer sequence will mistakenly bind the scaffold or oligos?
#**ClustalW says chances are not that great.
 
==Presentation Outline==
*'''Specific goal(s) of the project'''
**Proof of concept.  The idea of a generalizable, injectable, triggerable, clearable, simple-to-engineer protein manipulation system is a goal well worth working towards, as is building a useful DNA nanostructure. 
**'''state an existing problem and the impact if we solve it'''
***Anti-thrombotics are needed for patients who have a tendency towards thrombosis, embolisms, and stroke - a highly-molar-controlled, triggerable form could be extremely helpful for patients that demand fast action and close regulation.
 
*'''Initial ideas for how to solve the problem'''
**'''Unique/interesting features of our approach'''
***Generalizability: Because DNA aptamer designed to bind a protein in the bloodstream can be easily engineered into the structure, the design can be generalized simply.
***Molar-Triggerability: Because the strand-replacement-clasp system functions as a "lock and key" on a 1:1 molar level, tight control of thrombin inactivation and pulse-inactivation (due to the quick 5-10 min clearance of "key" strand) are obtainable.
***Coolness Factor: Because it's iGEM, and it'll look awesome.
***Novelness: Even if we fail on further levels, simply building a box is novel
 
**'''What pieces of the project do you already have a good idea that they can & will work?  what is novel?'''
***Jack-able:
****Tetrahedron concept, and possibly sequence, if we go w/ the open-surface model (a la http://www.sciencemag.org.ezp1.harvard.edu/cgi/content/full/310/5754/1661/FIG1)
****Thrombin-aptamer sequence
****Endo-incorporation of aptamer into oligo sequences (a la http://www3.interscience.wiley.com.ezp1.harvard.edu/cgi-bin/fulltext/110526995/PDFSTART)
****DNA tweezer strand-replacement sequence - though we can easily create one ourselves to hold a vertex of the tetrahedron together
***Novel:
****Design and sequence, if not going with the open-tetrahedron
 
*'''Logistics'''
**'''outline of project milestones and suggestions for division of labor'''
#Design a box with strand-displaced clasp (group) - we should design at least two different kinds of boxes.
#Write code to design box with oligo staples without aptamers, for testing, and with aptamers; (4 people at least, 2 per box)
#Test closed box w/o aptamers to see if it actually opens (gel studies should be good enough to show this).
##Simultaneously, test closed box w/ aptamers to see if it still opens (2 people at least).
#Test closed box w/o aptamers to see if it opens in presence of thrombin. (2 people at least)
##Simultaneously, test open box to see if aptamers on inner box surface actually bind thrombin (again, gel studies - or perhaps Western blot) (1 person).
#Test closed boxes w/ aptamers in in vitro system with thrombin, adding strand-displacement oligo after.  See if it sequesters (1 person)
#PEG-enclosure?
 
*'''Costs'''
**$$$
**Time
*'''Potential iGEM problems'''
**articulating how this fits into iGEM
**BioBricks
*'''Brief Summary'''
 
**We are trying to solve problem X with approach'''
**'''if we are successful, what will we be able to deliver in November'''
***Openable, triggerable box that binds thrombin and has a chance of being biostable
**'''if we are unsuccessful, what will we be able to deliver in November'''
***Box designs, possibly a non-opening box
 
==Tasks/agenda==
 
*design boxes with strand-displaced clasp
**design = determine oligo sequences
**several different models of boxes
**for each box, make a design that includes aptamers and one that doesn't
**try to keep designs modular, so that same set of oligos could create different structures in different combinations
**Nick's idea: closed-face tetrahedron
**other ideas: closed-face cube, capped honeycomb hexagon
**Shawn's recommendation: stick to modifications of honeycombs
*test boxes to see if they open and close
**gel studies
**imaging studies
**test aptamer/non-aptamer boxes in parallel
*test boxes to see if they close (and entrap) thrombin
**test aptamer/non-aptamer boxes in parallel
**simultaneously, test open box to see if aptamers on inner box surface actually bind thrombin
***again, gel studies, or perhaps Western blot
*test closed boxes w/ aptamers in ''in vitro'' system with thrombin, adding strand-displacement oligo after, see if it sequesters (1 person)
*engineer boxes with PEG, repeat tests
*possibility of incorporation with cells that present displacement DNA strands
 
==Box designs==
 
===Notes about designs===
 
'''Calculating coil length''': The distance between stacked base pairs is approximately (3.4 nm / turn) / (10.5 bp / turn) = 0.324 nm / bp.
*I'm not 100% sure that this figure is correct, so I will call it ''n'' until we can verify it with Dr. Shih. [[User:Matthewmeisel|Matthewmeisel]] 21:26, 20 June 2006 (EDT)
'''Calculating sheet length''': The length of a "sheet" can be calculated using simple trigonometry, as demonstrated by the diagram below.
*The effective diameter of a coil is 3 nm according to Dr. Shih, but I'm not 100% sure that this figure is correct, so I will call it ''d'' until we can verify it. [[User:Matthewmeisel|Matthewmeisel]] 21:26, 20 June 2006 (EDT)
 
===Designs===
 
based on ''n'' = 0.324 nm, ''d'' = 3.0 nm
 
{| {{table}}
| align="center" style="background:#f0f0f0;"|'''Shape'''
| align="center" style="background:#f0f0f0;"|'''Lid ply'''
| align="center" style="background:#f0f0f0;"|'''Cylinder design'''
| align="center" style="background:#f0f0f0;"|'''Lid design'''
| align="center" style="background:#f0f0f0;"|'''Total scaffold length'''
|-
| hexagon||single||42 tubes (33 nm dia) x 84 bp long (27.5 nm)||16 tubes (36 nm) x 126 bp long (41 nm)||7560
|-
| hexagon||double||30 tubes (24.2 nm dia) x 84 bp long (27.5 nm)||26 tubes (28.5 nm) x 84 bp long (27.5 nm)||6888
|}
 
==Bibliography==
 
===Thrombin===
<biblio>
# thr1 pmid=15170395
# thr2 pmid=6996572 
# thr3 pmid=1931959
# thr4 pmid=11032851
</biblio>
<br>
 
===Thrombin-Aptamer===
<biblio>
# tha1 pmid=8107090
# tha2 pmid=15945116
# tha3 pmid=8298130
</biblio>
<br>
 
===DNA Bioavailability===
<biblio>
# bioa1 pmid=16146351
# bioa2 pmid=11336355
# bioa3 pmid=7667185
</biblio>
<br>
 
===PEG Covering===
<biblio>
# peg1 pmid=15771224
# peg2 pmid=12922153
</biblio>
<br>
 
===Tetrahedral Structure===
<biblio>
# tet1 pmid=16339440
# tet2 pmid=2017259
</biblio>
<br>
 
===Strand Displacement Clasp===
<biblio>
# sdc1 pmid=11308883
# sdc2 pmid=10949296
</biblio>

Latest revision as of 18:15, 28 October 2006



Project Overview

  • Our goal is to design and implement molecular containers, which can be dynamically opened and closed by an external stimulus.
  • The containers will be implemented as DNA nanostructures, which afford a significant degree of positional control and chemical versatility.
  • As an initial proof-of-concept, we plan to use our DNA containers to demonstrate controllable activation ("delivery") of anti-thrombin aptamers.
  • We expect that molecular containers could have several interesting scientific and clinical applications, such as
    • Drug and gene delivery
    • Bio-marker scavenging (early detection of biomarkers)
    • Directed evolution (compartmentalized selections)
    • Using multiplexing for combinatorial chemical synthesis
    • Capture and stabilization of multiprotein complexes
    • Protein folding (chaperones)
    • Cell sorting

Working Team Members

Recent Changes

List of abbreviations:
N
This edit created a new page (also see list of new pages)
m
This is a minor edit
b
This edit was performed by a bot
(±123)
The page size changed by this number of bytes

24 April 2024

     22:47  WAKNA:Basics‎‎ 7 changes history +474 [Berthold Drexler‎ (7×)]
     
22:47 (cur | prev) +238 Berthold Drexler talk contribs (→‎Neuromonitoring allgemein)
     
22:33 (cur | prev) +151 Berthold Drexler talk contribs (→‎Hier finden Sie Literatur für Einsteiger:innen in das Gebiet der Neuroanästhesie)
     
22:31 (cur | prev) 0 Berthold Drexler talk contribs (→‎Grundlagen, Physiologie & Pharmakologie)
     
22:30 (cur | prev) +1 Berthold Drexler talk contribs (→‎Grundlagen, Physiologie & Pharmakologie)
     
22:30 (cur | prev) +313 Berthold Drexler talk contribs (→‎Grundlagen, Physiologie & Pharmakologie)
     
06:23 (cur | prev) +192 Berthold Drexler talk contribs (→‎Hier finden Sie Literatur für Einsteiger:innen in das Gebiet der Neuroanästhesie)
     
06:21 (cur | prev) −421 Berthold Drexler talk contribs (→‎Sonstige)
     18:35  User:Yanbin Huang‎‎ 2 changes history +25 [Yanbin Huang‎ (2×)]
     
18:35 (cur | prev) +13 Yanbin Huang talk contribs (→‎Peer-Reviewed Publications)
     
18:34 (cur | prev) +12 Yanbin Huang talk contribs (→‎Peer-Reviewed Publications)
     17:49  Hu‎‎ 2 changes history +28 [Hugangqing‎ (2×)]
     
17:49 (cur | prev) +18 Hugangqing talk contribs
     
17:48 (cur | prev) +10 Hugangqing talk contribs
     08:14  "Pick and Place" Assembly of Parts Using PDMS - Amy Lim, Rylie Costello‎‎ 6 changes history +394 [Rcostello‎ (6×)]
     
08:14 (cur | prev) +1 Rcostello talk contribs (→‎"Pick and Place" Methodology)
     
08:13 (cur | prev) −14 Rcostello talk contribs (→‎"Pick and Place" Methodology)
     
08:12 (cur | prev) −1 Rcostello talk contribs (→‎"Pick and Place" Methodology)
     
08:12 (cur | prev) −1 Rcostello talk contribs (→‎"Pick and Place" Methodology)
     
08:12 (cur | prev) +110 Rcostello talk contribs (→‎References)
     
08:11 (cur | prev) +299 Rcostello talk contribs (→‎"Pick and Place" Methodology)
     08:02 Upload log Rcostello talk contribs uploaded File:Pick and Place.mp4

23 April 2024

     15:33  "Pick and Place" Assembly of Parts Using PDMS - Amy Lim, Rylie Costello‎‎ 6 changes history +837 [Rcostello‎ (6×)]
     
15:33 (cur | prev) +1 Rcostello talk contribs (→‎"Pick and Place" for Microfluidics)
     
15:33 (cur | prev) +203 Rcostello talk contribs (→‎References)
     
15:31 (cur | prev) −2 Rcostello talk contribs (→‎"Pick and Place" for Microfluidics)
     
15:29 (cur | prev) −474 Rcostello talk contribs (→‎References)
     
15:29 (cur | prev) +845 Rcostello talk contribs (→‎MEMS Devices)
     
15:14 (cur | prev) +264 Rcostello talk contribs (→‎"Pick and Place" for Microfluidics)
     11:58  BioMicroCenter:People‎‎ 2 changes history +30 [Lttran‎ (2×)]
     
11:58 (cur | prev) −4 Lttran talk contribs (→‎BioMicro Center Staff)
     
11:49 (cur | prev) +34 Lttran talk contribs (→‎BioMicro Center Staff)
     11:46 Upload log Lttran talk contribs uploaded File:SKR BMC.jpg

22 April 2024

     19:28  "Pick and Place" Assembly of Parts Using PDMS - Amy Lim, Rylie Costello‎‎ 4 changes history +1 [Rcostello‎ (4×)]
     
19:28 (cur | prev) −2 Rcostello talk contribs (→‎Nanowires)
     
19:26 (cur | prev) 0 Rcostello talk contribs (→‎Biology-Inspired Solution)
     
15:03 (cur | prev) +2 Rcostello talk contribs (→‎At the Microscale)
     
15:02 (cur | prev) +1 Rcostello talk contribs (→‎Overview)
     19:01  Microfluidic Sensing- Microfluidic Biosensors- Xiao Fan‎‎ 17 changes history +391 [Khiemle‎ (17×)]
     
19:01 (cur | prev) +14 Khiemle talk contribs (→‎Microfluidic immunosensors)
     
19:00 (cur | prev) +7 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
19:00 (cur | prev) +18 Khiemle talk contribs (→‎Microfluidic immunosensors)
     
18:59 (cur | prev) +18 Khiemle talk contribs (→‎Microfluidic immunosensors)
     
18:58 (cur | prev) −2 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
18:58 (cur | prev) +2 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:58 (cur | prev) +1 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:58 (cur | prev) −9 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:57 (cur | prev) −40 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
18:57 (cur | prev) +2 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
18:56 (cur | prev) +34 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
18:56 (cur | prev) +86 Khiemle talk contribs (→‎Microfluidic immunosensors)
     
18:54 (cur | prev) 0 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:54 (cur | prev) −10 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:53 (cur | prev) +108 Khiemle talk contribs (→‎Enzyme-based microfluidic biosensors)
     
18:51 (cur | prev) +84 Khiemle talk contribs (→‎DNA-based microfluidic biosensors)
     
18:49 (cur | prev) +78 Khiemle talk contribs (→‎Microfluidic biosensors)
     09:24  CHEM-ENG590E:Wiki Textbook diffhist +16 Rcostello talk contribs (→‎Chapter 15 - Other Topics)
     09:24 Move log Rcostello talk contribs moved page "Pick and Place" Assembly of Parts Using PDMS - Amy Lim to "Pick and Place" Assembly of Parts Using PDMS - Amy Lim, Rylie Costello