Figure 1. Integrating a synthetic RNA–protein interaction module with native translation control mechanisms.

(a) Several previously implemented approaches for posttranscriptional regulation of gene expression in eukaryotes are summarized. These are classified as ‘uni-dimensional' since primarily one activity determines the availability or accessibility of a target transcript for translation. (b) Schematic of the proposed strategy for integrating a synthetic RNA–protein module with host cell translation control mechanisms to achieve ‘multi-dimensional', posttranscriptional regulation of gene expression. Fusing the regulatory protein in the synthetic module to host cell factors involved in controlling RNA turnover, degradation and sequestration is proposed as an approach for extending the dynamic range and reducing leaky expression of the synthetic system. Direct control of gene expression is achieved by toggling the synthetic RNA–protein interaction via a small-molecule inducer.