The RNA interference (RNAi) pathway is a naturally occurring mechanism in which regulatory non-coding RNAs (ncRNAs) suppress gene expression by targeting messenger RNAs (mRNAs). The RNAi technique is used in molecular biology laboratories and biotechnology applications to reduce the expression of target genes by delivering small interfering RNA (siRNA) molecules targeting a gene of interest. These siRNAs are artificially synthesized to bind by complementarity to the target mRNAs, thereby they can be used for transient gene silencing. This technique does not require genetic modification of the cells, sinceRNAi can be achieved by direct exogenous delivery of siRNAs.
Antibiotic resistance happens when an antibiotic lost its ability in controlling or killing bacterial growth. At this moment the bacteria are already resistant to the antibiotic and are multiplying even though the drug is present. This is a natural phenomenon.
