Project Description

Work in the past

Prion

1. Background

In yeast cell, there is a non-Mendelian inheritance system.

Figure 1: The effect of [PSIC] on Sup35 and translational termination. (A) A complex of Sup35 (see legend at bottom) and Sup45 binds ribosomes at stop codons and mediates translational termination. Sup35 is composed of two regions, a prion-determining-domain (PrD, rectangle) and a termination domain (Sup35C, sphere). In non-prion [ psi¡] strains, translational termination occurs efficiently at stop codons at the ends of open reading frames, and the completed protein is released from the ribosome.(B) In [PSIC] cells, most Sup35 proteins adopt the prion conformation and self-assemble into an aggregated, possibly amyloid structure (depicted as large cylinder). This conformational change impairs Sup35’s ability to participate in translational termination and consequently, stop codons are read through occasionally, producing proteins with a C-terminal extension.

Moreover, it shows that the PrD can be modularized, which means we can combine this domain to another protein we want to make them aggregate, and even impair its function.

Here is the most magical part ,not only can we make them aggregate, we can also cure our yeast by a great variety of chemical, environmental, and protein-based agents. Then these proteins will be depolymerized, and spread uniformly in the cell once again.

2. Application

We design three gene line.

In the first design (figure 2), we just use R9 to depolymerize the SUP35’s aggregation to allow the yeast to produce functional GFP. Then we can calculate the concentration of R9 through the fluorescent brightness.

In the second design (figure3), we build a double direction switch.

In the third design, GFP1 and GFP2 are not able to give out light separately. However, when they touch each other physically, they will reconstruct and give out light.

RNA

Goals in the future