AN AUTONOMOUS LINEAR DNA CLOCK

Richard J. Crossland

Overview

Requirements Objectives Two designs Implementation

Software development cycle Advantages of a linear DNA clock

Design 4: Exonuclease only

Mechanism for the linear DNA clock showing how telomere shortening eats away into genes that repress cell death pathways. Upon the destruction of the repressor gene by unrepaired telomere shortening, the cell-death pathway becomes uninhibited to kill the cell.

Requirements

A ‘construct that sequentially regulates gene expression after a time delay’. Allows ordered gene expression. Level of expression at each step is controllable. Can alter total time in the program and the

relative time of each step. There is a mechanism to initiate the program. Consistent program duration. Can be destroyed after program is complete.

The Software Development Cycle

Objectives

1. Design and simulate alternative models2. List and specify the parts for my

models3. Locate parts from the scientific

literature4. List parts that need synthesising5. Evaluate the best model in terms of:

meeting the requirements availability of existing parts

Design 4: Exonuclease only

Mechanism for the linear DNA clock showing how telomere shortening eats away into genes that repress cell death pathways. Upon the destruction of the repressor by unrepaired telomere shortening, the cell-death pathway becomes uninhibited to kill the cell.

Design 2: the ER2/gap model

An ER2 (exonuclease-resistant secondary structure)

gene1

2 3

Implementation in Java

Advantages of a linear DNA clock Timing specified by order and distance,

not concentration. Autonomous to the cell. Not dependent

on extracellular signals. Regulates expression of chromosomal or

linear DNA genes Ethical consideration: ensures the

destruction of all GM genes.