Conjugation

Part:BBa_K5170000

Designed by: Subhanan Banerjee, Suvam Saswat Das, Avani, Anurag Sarkar, Parth Kumar   Group: iGEM24_IISc-Bengaluru   (2024-10-01)


A novel PROTAC using BBa_K5170004 against 231pTau

The heterobifunctional molecule is a protein targeting chimera (PROTAC) employing BBa_K5170004 selected for 231pThreonine site in hyperphosphorylated Tau proteins as the POI targeting moiety, [S,R,S]-AHPC as the ligand to localise the PROTAC to the Von Hippen Lindau E3 ubiquitin ligase and ethylene glycol as the linker bound to both the parts. Use of an aptamer instead of antibodies or other molecules in a PROTAC is due to some unconventional properties like low immunogenicity, high specificity, ease of evolution to newer targets using different forms of SELEX, selectivity to microstructure and flexibility.

Hyperphosphorylation of Tau has been associated with several neurodegenerative diseases classified as Tauopathies which even includes Alzheimer's disease. This part may be used for degradation of hyperphosphorylated Tau which is expected to stipulate further elevation of symptoms in such disorders. This PROTAC may degrade pTau depending on the presence of phosphorylation at 231 Threonine site, an AD marker found to be significantly elevated in Alzheimer’s struck human brains compared to normal brains. Moreover, the use of aptamers (due to its easy evolution) retains the scope of extrapolating this PROTAC to other sites such as 217 Threonine, 198 Serine, 235 Serine,181 Threonine, 396 Serine etc.

C8 Alkyne dCTP can be clicked with [S,R,S]-AHPC-PEG1-Azide. After HPLC purification, it can be incorporated into the BBa_K5170004 by terminal deoxynucleotidyl transferase.


Usage and Biology

The binding region of the aptamer stays undisturbed if the modified ligand linked base is joined in the 3' terminal. The modified ligand linked base can be found on https://2024.igem.wiki/iisc-bengaluru/contribution

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


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Categories
Parameters
None