Linear Bounds on the Size of Conformations in Greedy Deterministic Oritatami

Abstract

Oritatami is a computational model of RNA cotranscriptional folding, in which an RNA transcript is folding upon itself while being synthesized from its template DNA. This model is known to be Turing universal. Under the restriction on its parameters delay and arity both being 1, however, any deterministically foldable conformation is known to be at most ten times as large as its initial conformation (seed), and hence, the model becomes weaker. In this paper, we shall improve the size upper bound from [Formula: see text] down to [Formula: see text] and also provide a system that can fold into a conformation of size [Formula: see text]. These tighter bounds result from a novel graph representation of deterministic oritatami folding pathways. We shall also study the case in which a transcript is trapped in a region closed by a seed and show that under this confinement, the upper bound is further improved to [Formula: see text].