Device

Part:BBa_K1150021

Designed by: M. Stammnitz   Group: iGEM13_Freiburg   (2013-09-17)
Revision as of 19:08, 4 October 2013 by NightworkMax (Talk | contribs)

uniCAS Repressor (SV40 promoter)

SV40:HA-NLS-dCas9-Linker-KRAB-NLS:BGH
Function Transcriptional Repression
Use in Mammalian cells
RFC standard RFC 25
Backbone pSB1C3
Organism Streptococcus pyogenes, Homo sapiens
Source Feng Zhang, Addgene
Konrad Müller, University of Freiburg
Submitted by [http://2013.igem.org/Team:Freiburg Freiburg 2013]
Krüppel-associated Box repressor domains - commonly termed as KRAB - are highly conserved polypeptide motifs and were first functionally characterized in 1991 (Rosati et al., 1991). As they constitute about one third of all human zinc finger transcription factors, key regulatory features in higher eukaryotic transcriptomics are suggested (Witzgall et al., 1994). Even in terms of tetrapod evolution, the role of their great abundance has been extensively discussed (Birtle, 2006). Even though KRAB minimal domains are usually no longer than 50-75 amino acids, their mechanism of function remains complex.

Common biochemical models suggest a key role in epigenetic silencing, by recruiting a scaffold of diverse proteins - amongst others histone deacetylases and histone methyltransferases (Urrutia, 2003). Til date in 2013, KRAB repressor domains were attached to several DNA binding proteins such as tetR, TAL effectors and [http://2013.igem.org/Team:Freiburg dCas9] - thereby efficiently silencing gene expression downstream of desired target promoters.

In this attempt, an SV40 promoter was cloned in front of a RFC25-conformal dCas9. Flanked by two NLS, complemented with an HA-Tag for Western blot detections and fused to KRAB with a net 7 amino acid linker, this resulted in the here-shown composite part.
Fig. 1 Schematic overview of the dCas9-KRAB composite part with all features.

Theoretically, this functional repressor can be directed towards almost any gene or promoter of interest, by harnessing a specifically designed [http://2013.igem.org/Team:Freiburg/Project/crrna#rnaimer RNAimer plasmid]. Two corresponding 30-basepair of the desired target

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal BglII site found at 664
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI.rc site found at 4784
    Illegal SapI.rc site found at 4748

Functional Parameters

[edit]
Categories
Parameters
None