Part:BBa_K2493004
Antisense Sok
Usage and Biology
The Sok RNA serves as the antitoxin within the Hok/Sok toxin-antitoxin system. The system facilitates plasmid maintenance within growing bacteria.
In particular, the system is designed to kill the cells that lack the plasmid containing the Sok gene. The Hok protein is very stable and acts as a toxin to the cell when it is expressed. Specifically, Hok depolarizes the cell membrane, leading to cell death. However, the Sok RNA post-transcriptionally regulates the expression of Hok. Sok is complementary to the leader region of the Hok mRNA. Through its association with the leader region, Sok inhibits the translation of the toxic Hok protein, preventing cell death. However, the Sok RNA is very unstable and it is degraded quickly. Therefore, the plasmid containing the Sok gene is necessary for the survival of the cell, if it contains the Hok gene.
Using this toxin-antitoxin system, the maintenance of particular plasmids can be controlled.
Design Considerations
We wanted to synthesize an antisense RNA for the HokD gene (BBa_K1497008); however, it was not feasible because HokD contains a large hairpin loop within its sequence. Moreover, the GC content of this hairpin loop was also very high. Therefore, we decided to create a separate Hok/Sok system through synthesis with IDT (Integrated DNA Technologies).
Source
We had this part synthesized from IDT (Integrated DNA Technologies).
References
Gerdes, K., Thisted, T. & Martinussen, J. Mechanism of post-segregational killing by the hoklsok system of plasmid R1: sok antisense RNA regulates formation of a hok mRNA species correlated with killing of plasmid-free cells. Molecular Microbiology 4, 1807-1818, doi:10.1111/j.1365-2958.1990.tb02029.x (1990).
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
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