Synthetic RNA-based biocomputing devices

Synthetic RNA-based devices
--Programming cellular networks using
synthetic riboregulators
--Synthetic Microbiology
Heinrich-Heine-Universität Düsseldorf
24.06.2014
Synthetic RNA-based devices
--Programming cellular networks using
synthetic riboregulators
--Synthetic Microbiology
Heinrich-Heine-Universität Düsseldorf
24.06.2014
Synthetic RNA-based biocomputing devices
Synthetic RNA signaling networks
TBI Vienna
Düsseldorf/
Berlin
www.ribonets.eu
1/ 19
CNRS Paris
Synthetic RNA-based biocomputing devices
Outline
Overview: base-pairing sRNAs in bacteria
One example from the cyanobacterium Synechocystis sp. PCC 6803
PsrR1 – a negative regulator of photosynthesis-related mRNAs
In silico design of RNA devices
Example: Repression through switching
Strategies for in vivo analysis
Application: metabolic engineering
2/ 19
RNA - a versatile regulator
trans-encoded base-pairing sRNAs
´negative regulation´
• Blocking ribosome binding site (RBS)
• Targeting coding sequence (CDS)
 degradation of sRNA-mRNA duplex by
RNases
´positive regulation´
• Preventing the formation of an
inhibitory structure
Waters & Storz, 2009
3/ 19
 release of RBS
RNA - a versatile regulator
base-pairing with target mRNAs
limited complementarity
 multiple target sequences
6-7 nt for ‘‘seed-pairing’’
 decrease/increase ribosome binding
and/or mRNA stability
E. coli
80-100 sRNAs
Gottesman & Storz, 2011
Y. pseudotubercolosis
165 sRNAs
Koo et al., 2011
Synechocystis 6803
Mitschke et al., 2011
4/ 19
314 trans-sRNAs
1011 asRNAs for 866 genes
Natural RNA regulators in cyanobacteria (Synechocystis sp. PCC 6803)
Example 1: trans-encoded sRNA PsrR1
PsrR1 accumulates under High Light & Ci limitation
PsrR1
psaL
PsrR1
Northern Blot
Anti-SD
Mitschke, Georg, Scholz, Sharma, Dienst, Bantscheff, Voß, Steglich, Wilde, Vogel, Hess. PNAS 2011
Georg, Dienst, Schürgers, Kuchmina, Wallner, Klähn, Knoop, Lokstein, Hess, Wilde. Submitted
5/ 19
Natural RNA regulators in cyanobacteria (Synechocystis sp. PCC 6803)
Example 1: trans-encoded sRNA PsrR1
PsrR1 targets psaL mRNA
EMSA
Mitschke, Georg, Scholz, Sharma, Dienst, Bantscheff, Voß, Steglich, Wilde, Vogel, Hess. PNAS 2011
Georg, Dienst, Schürgers, Kuchmina, Wallner, Klähn, Knoop, Lokstein, Hess, Wilde. Submitted
6/ 19
Natural RNA regulators in cyanobacteria (Synechocystis sp. PCC 6803)
Example 1: trans-encoded sRNA PsrR1
Constitutive and pulsed overexpression provides insight into PsrR1 function
PC Chl a
control psrR1+
psrR1+
Car
Western Blot
BN PAGE
Mitschke, Georg, Scholz, Sharma, Dienst, Bantscheff, Voß, Steglich, Wilde, Vogel, Hess. PNAS 2011
Georg, Dienst, Schürgers, Kuchmina, Wallner, Klähn, Knoop, Lokstein, Hess, Wilde. Submitted
Annegret Wilde
7/ 19
Wolfgang R. Hess
RNA-based biocomputing devices
Synthetic RNA signaling networks
TBI Vienna
Düsseldorf/
Berlin
www.ribonets.eu
11/ 19
CNRS Paris
RNA-based biocomputing devices
In silico design of RNA devices
Christoph
Sven
Stefan
analysis and selection of the best solutions by machine learning approach
Höner zu Siederdissen, C., Hammer, S., Abfalter, I., Hofacker, I. L., Flamm, C., & Stadler, P. F. (2013). Biopolymers, 99(12), 1124-1136.
12/ 19
RNA-based biocomputing devices
Status:
In total 6 RNAdev candidates:
Direct OFF Switch C99 and F34
Direct ON Switch A94 and E63
Indirect OFF Switch D50 and H60
13/ 19
RNA-based biocomputing devices
Example: Repression through switching - indirect
Solution H60
sRNA
5‘UTR
SD
SD
Sequence constraints:
• Leading A
• Terminator loop sequence (GCGAAAGC)
Sequence constraints:
•
•
•
•
pos 1-14 (ACCCGTTTTTTTGG)
SD sequence (AAGGAG)
Length between RBS and start codon (7N)
Start Codon (ATG)
RNA-RNA duplex
14/ 19
RNA-based biocomputing devices
Example: Repression through switching
in vivo analysis
RNAdev 1
IPTG
ATc
RNAdev 1
YFP
YFP
+
yfp
E. coli
E. coli
RNAdev 2
ATc
IPTG
CFP
cfp
E. coli
15/ 19
yfp
RNAdev 2
CFP
+
cfp
E. coli
RNA-based biocomputing devices
Example: comparator device
in vivo analysis
YFP
yfp
Input signals
CFP
cfp
RNAdev 2
E. coli
YFP
RNAdev 1
IPTG
yfp
+
+
cfp
cfp
E. coli
16/ 19
CFP
Output signals
+
+
ATc
RNAdev
comparator
yfp
RNA-based biocomputing devices
Example: comparator device
in vivo analysis
… in Cyanobacteria
yfp
RNAdev
comparator
Input signals
ATc
RNAdev 2
RNAdev 1
IPTG
+
+
cfp
yfp
zFP
cfp
Synechocystis
xFP
yfp
cfp
Synechocystis
17/ 19
Output signals
+
+
xFP
?
zFP
?
Application: metabolic engineering
production of antimalarial drug artemisinin (Keasling, 2012; Martin et al., 2003)
problem: intermediate toxic compounds accumulate
solution: RNA-based comparator
J. Keasling
18/ 19
Application: metabolic engineering
our strategy: extended comparator → self-adjustment & balancing of two branches
19/ 19
Our Team
Düsseldorf
Ilka Axmann
Berlin
Jennifer Andres
Janos Jablonski
Katharina Wiebe
Dennis Dienst
Tim Kolmsee
Stefanie Hertel
Christian Beck
Adrian Kölsch
Beate Heilmann
Rainer Machné
Julian Balzer
Anika Wiegard
Jan-Philipp Kunz
… and collaborators:
IMET Jülich:
Karl-Erich Jaeger
Thomas Drepper
Anita Loeschcke
Dennis Binder
15/
19
TBI Vienna:
Christoph Flamm
Sven Findeiß
Stefan Hammer
CNRS Paris:
André Estévez-Torres
Jonathan Lee Tin Wah
Thank you for your attention !!!