The leading sequence involved in the YtfJ transcript which can act as the target of the sRNA, spot42. It enables strong competition with the galk::GFP to interact with spot42 which shows great potential for constructing sRNA-mediated circuit. Small RNA Spot42 controls the GFP mRNA translation by blocking the RBS in galK.The galK and E0040 is fused together using ClaI site to avoid stop condon in standard scar.J23106 is a moderate promotor,and galK???s RBS is a moderate one. Spot42 sRNA is under control of aTc inducible device,the buffer RNA YtfJ is under control of IPTG inducible device.IPTG/aTc concentration gradient results in different YtfJ RNA/sRNA Spot42 levels in cells, which can be monitored by our galK::GFP generator(where galK is the RBS of GFP and the target for Spot42) ,Spot42 can be buffered by YtfJ_Spot42 Scaffold fusion RNA.
References: [1]Chase L. Beisel and Gisela Storz, The Base-Pairing RNA Spot 42 Participates in a Multioutput Feedforward Loop to Help Enact Catabolite Repression in Escherichia coli. Molecular Cell 41, 286???297, February 4, 2011
Lutz, R., Bujard, H., Nucleic Acids Research (1997) 25, 1203-1210.
Sequence for pTet inverting regulator driven by the TetR protein.
BBa_R0040 TetR-Regulated Promoter is based on a cI promoter. It has been modified to include two TetR binding sites and the BioBrick standard assembly head and tail restriction sites.
June Rhee, Connie Tao, Ty Thomson, Louis Waldman
Promoter (lacI regulated, lambda pL hybrid)
represillator of Elowitz and Leibler (2000)
Inverting regulatory region controlled by LacI (<bb_part>BBa_C0010</bb_part>, <bb_part>BBa_C0011</bb_part>, etc.) The PLlac 0-1 promoter is a hybrid regulatory region consisting of the promoter P(L) of phage lambda with the cI binding sites replaced with lacO1. The hybrid design allows for strong promotion that can nevertheless be tightly repressed by LacI, the Lac inhibitor (i.e. repressor) (<bb_part>BBa_C0010</bb_part>) ([LUTZ97]). The activity of the promoter can be regulated over a >600-fold range by IPTG in E.Coli DH5-alpha-Z1 (same paper reference).
hybrid promoter design to create strong promoter that is, at the same time, highly repressible. note that the upstream operator installed in this hybrid is slightly different than the one in the original source (Lutz and Bujard, 1997). the most upstream operator region is slightly truncated in the represillator version, so that both operators in the hybrid are the same sequence. see references for details. also, the sequence has been truncated after the transcriptional start site. LacI binds to this regulator. This part is incompatible with species containing active LacI coding regions. Lactose and IPTG disable the operation of LacI and increase transcription. This part is incompatible with environments containing lactose or lactose analogs.
Neelaksh Varshney, Grace Kenney, Daniel Shen, Samantha Sutton
Spot42 is a multitarget small RNA that mediates the discoordinate expression of the E.coli galactose
Spot42 is a multitarget small RNA that mediates the discoordinate expression of the E.coli galactose operon and other sugar metabolic pathway,such as galK,nanC,ytfJ,srlA,which are the 5??? leader sequence of the corresponding metabolic enzymes. Take galK for example,Spot42 causes translation repression by base pairing to RBS in the 5??? leader sequence,then block the recognition of the antiSD sequence on 30S subunit. It???s a very strong pairing(up to 20bases),but it only causes 2.6 fold repression according to Johannes H. Urban and Jo?? rg Vogel,for it doesn???t result in the degradation of the RNA complex by RNaseE(ssRNA degradation) and RNaseIII(dsRNA degradation),both of them are major enzymes that causes RNA degradation in vivo.Spot42-galK complex degrades in a slow and presently unclear way. The base pairing is initiated by the recognition of seed region,which plays a significant role in the repression efficiency. Small RNA chaperone Hfq is an abundant protein that has 40000~50000 copies each cell,accelerating annealing and strand-exchange between small RNAs and target mRNA.Hfq binds to the AU-rich domain of small RNA,and footprinting experiments has shown that Hfq protects the degradation of RNA from RNase.It is essential to most of small RNAs in E.coli,extremely enchances the repression efficiency. Spot42 have a weak Hfq binding site(whereas galK weaker),an endogenous terminator(unclear efficiency,maybe weak),and the multitarget repression stem-loop.
References: [1] Vandana Sharma, Asami Yamamura, and Yohei Yokobayashi,Engineering Artificial Small RNAs for Conditional Gene Silencing in Escherichia coli,ACS Synthetic Biology
The leading sequence involved in the YtfJ transcript which can act as the target of the sRNA, spot42
The leading sequence involved in the YtfJ transcript which can act as the target of the sRNA, spot42. It enables strong competition with the galk::GFP to interact with spot42 which shows great potential for constructing sRNA-mediated circuit.
RBS (Elowitz 1999) -- defines RBS efficiency
Varies from -6 to +1 region from original sequence to accomodate BioBricks suffix. No secondary structures are formed in the given RBS region. Users should check for secondary structures induced in the RBS by upstream and downstream elements in the +50 to -50 region, as such structures will greatly affect the strength of the RBS. Contact info for this part: Brian Chow
Vinay S Mahajan, Voichita D. Marinescu, Brian Chow, Alexander D Wissner-Gross and Peter Carr IAP, 2003.
Derived from the TE terminator of T7 bacteriophage between Genes 1.3 and 1.4 <genbank>V01146</genbank>.
Transcription terminator for the E.coli RNA polymerase.
Suggested by Sri Kosuri and Drew Endy as a high efficiency terminator. The 5' end cutoff was placed immediately after the TAA stop codon and the 3' end cutoff was placed just prior to the RBS of Gene 1.4 (before AAGGAG). Use anywhere transcription should be stopped when the gene of interest is upstream of this terminator.
Transcriptional terminator consisting of a 64 bp stem-loop.
Coding region for the LacI protein with an LVA degradation tail and without an RBS. LacI binds to the pLac regulator <bb_part>BBa_R0010</bb_part> and PLlac01 hybrid regulator <bb_part>BBa_R0011</bb_part> and inhibits transcription. IPTG (Isopropylthiogalactoside) binds to LacI and inhibits its operation, therefore promoting transcription. A rapid degredation tail (LVA) has been added to improve the High to Low performance of this part.
References (unparsed) here: Elowitz, M.B., Leibler, S. A synthetic oscillatory network of transcriptional regulators. Nature 403, 335-338 (2000). [ELOW00] References (unparsed) here: Elowitz, M.B., Leibler, S. A synthetic oscillatory network of transcriptional regulators. Nature 403, 335-338 (2000). [ELOW00] Sequence taken from the repressilator of Elowitz and Leibler (2000). The obtained sequence was compared to the wild-type sequence for LacI obtained through a database search. The sequence had been modified from the wild-type in that wild-type GTG start was changed to an ATG start (note, actual ORF in E.coli has several GTG starts it would seem). The LVA tag has been added for quicker degradation. Incompatible with systems containing LacI, lactose, or IPTG.
Grace Kenney, Daniel Shen, Neelaksh Varshney, Samantha Sutton
tetracycline repressor from transposon Tn10 (+LVA)
Elowitz, M. B. Transport, Assembly, and Dynamics in Systems of Interacting Proteins. Thesis, Princeton Univ., Princeton (1999)
Coding region for the TetR protein without the Ribosome Binding Site. Modified with an LVA tail for rapid degradation of the protein and faster fall time for the emission. TetR binds to the pTet regulator (BBa_R0040). aTc (anhydrotetracycline) binds to TetR and inhibits its operation.
References (unparsed) here: Elowitz, M. B. Transport, Assembly, and Dynamics in Systems of Interacting Proteins. Thesis, Princeton Univ., Princeton (1999). Lutz R, Bujard H., Independent and tight regulation of transcriptional units in Escherichia coli via the LacR/O, the TetR/O and AraC/I1-I2 regulatory elements. Nucleic Acids Res. 1997 Mar 15;25(6):1203-10. PMID: 9092630 References (unparsed) here: Elowitz, M. B. Transport, Assembly, and Dynamics in Systems of Interacting Proteins. Thesis, Princeton Univ., Princeton (1999). Lutz R, Bujard H., Independent and tight regulation of transcriptional units in Escherichia coli via the LacR/O, the TetR/O and AraC/I1-I2 regulatory elements. Nucleic Acids Res. 1997 Mar 15;25(6):1203-10. PMID: 9092630 BBa_C0040 TetR Protein is based on the TetR sequence from Elowitz's repressilator. It has been modified to include a rapid degradation LVA tail, and includes the BioBrick standard assembly head and tail restriction sites. The RBS has been removed. The stop codon has been changed from TAA to a double stop codon TAATAA.
June Rhee, Connie Tao, Ty Thomson, Louis Waldman.
Conversion of the iGEM parts registry to SBOL2.1