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Small interfering RNAs, or siRNAs, are non-coding RNAs, about 22 nucleotides long, that regulate mRNA synthesis and stability.
siRNA can originate from within the cell by DNA transcription, can be processed from viral RNA, or can be added by scientists for experimental purposes.
siRNAs are processed from long double-stranded RNA. This RNA is cleaved into multiple short siRNAs with the help of an endonuclease, Dicer.
Each siRNA then binds to Argonaute, along with other proteins, leading to the formation of the RNA induced silencing complex, or RISC.
In RISC, the RNA guide strand is separated from its complementary strand and remains in the complex, so it can then pair with the target mRNA. Then, the target mRNA is cleaved with the help of Argonaute and subsequently degraded in the cytoplasm.
During their life cycle, RNA based viruses enter a host cell and produce double-stranded RNA. This RNA is recognized by Dicer and processed into siRNA. These siRNAs help fight viral infections by promoting the degradation of viral mRNA.
In the nucleus, centromere-associated DNA repeats encode transcripts that are processed by Dicer to produce specific types of siRNA. Unlike cytoplasmic siRNA
Kleine interfererende RNA's, of siRNA's, zijn korte regulerende RNA-moleculen die genen post-transcriptioneel tot zwijgen kunnen brengen, en in sommig…
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