Team:MIT/L7AeRepressingSystem

L7Ae k-turn repressing system

L7Ae - Kink turn

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RNA-Based Gene Regulation

L7Ae, an archaeal ribosomal protein, binds with high affinity to RNA motifs called kink-turns (K-turns), found in both archaeal and eukaryote RNAs [1][2][3]. L7Ae protein sequence is divided into three structural regions consisting of a highly conserved RNA-binding region (RBR) flanked by less conserved N-terminal and C-terminal regions [2]. Variation in the terminal regions could dictate RNA-binding specificity of different homologs of L7Ae protein [2]. When a K-turn motif is inserted into the target mRNA upstream of the open reading frame, L7Ae can be used as a translational regulator [1][2][3]. The binding activity of L7Ae will prevent the ribosome machinery from performing translation. The strength of the repression can be controlled by varying the distance between the K-turns and the 5’-end of the mRNA, or by changing the number of the k-turn motifs [1].

Read more about building kturn constructs here.

Recombinase and L7Ae-Kturn

Purpose

Experimental Setup

Result

Testing the 2x k-turn L7Ae system with varied L7Ae expression level

Testing the effect of varying k-turn sequences



REFERENCE:

  1. Oliwia Andries, Tasuku Kitada, Katie Bodner, Niek N Sanders & Ron Weiss (2015) Synthetic biology devices and circuits for RNA-based ‘smart vaccines’: a propositional review, Expert Review of Vaccines, 14:2, 313-331
  2. Gagnon KT, Zhang X, Qu G, et al. Signature amino acids enable the archaeal L7Ae box C/D RNP core protein to recognize and bind the K-loop RNA motif. Rna 2010;16(1):79-90
  3. Stapleton JA, Endo K, Fujita Y, et al. Feedback control of protein expression in mammalian cells by tunable synthetic translational inhibition. ACS Synth Biol 2012;1(3):83-8