RNA

Part:BBa_K2976005

Designed by: Jiatong Chen   Group: iGEM19_CPU_CHINA   (2019-08-03)
Revision as of 01:47, 5 September 2019 by NF-kB pathway (Talk | contribs)


hsa-let-7f pri-miRNA

MicroRNAs (miRNAs) are a group of non-coding RNA molecules of 19-25 nt in length that regulates post-transcriptional gene expression. The let-7 miRNA was one of the first miRNAs discovered in the Caenorhabditis elegans and its biological functions show a high level of evolutionary conservation from nematode to human.

Usage

In 2019 CPU_CHINA project, we deliver the hsa-let-7f miRNA into Mtb-infected macrophages to promote their bioactivities. External supplement of let-7f could alleviate the decrease of it caused by Mtb and increase the expression of a series of pro-inflammatory cytokines and chemokines, such as TNF-α, IL-1β, IL-6, KC, MCP-1, MIP-2 and nitrite. Then the anti-TB activity of macrophages renews and the intracellular Mtb will be killed.

Biology

MicroRNA (miRNA) act as post-transcriptional gene suppressors by base-pairing with their target mRNAs and inducing either translational repression or mRNA destabilization. Their genes are transcribed as primary miRNAs (pri-miRNAs) by RNA polymerase II (Pol II) in the nucleus. The long pri-miRNAs are cleaved by Drosha and DiGeorge syndrome critical region 8 (DGCRB), to produce 60-70 nt precursor miRNAs (pre-miRNAs). The pre-miRNAs are then exported and further processed by Dicer to produce the mature miRNAs.

MicroRNA hsa-let-7f is reported to regulate human immune responses to Mtb via control of A20, an inhibitor of the NF-κB pathway. The Nuclear factor-kappa B (NF-κB) family of transcription factor plays an essential role in regulating the expression of pro-inflammatory cytokine and chemokine genes, which is regarded as the central mediator of inflammatory process. However, Kumar et al. show that Mtb suppresses innate immune responses via inhibiting microRNA let-7f expression, which facilitates the survival of Mtb in macrophages. It is tempting to speculate that targeted intervention of miRNA regulated processes could provide attractive host-directed therapies for management of mycobacterial diseases.


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
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