Name Akio Kawauchi Osaka City University Session Jan 9 13:00~13:40 E11-103 Topology of prion proteins The content of this talk is a joint work with Kayo Yoshida. A topological model of prion proteins ($PrP^C$, $PrP^{SC}$) which we call a prion-tangle is proposed to explain some entangling properties of prion proteins by a knot theoretical approach. We show that two splitted prion-tangles can be changed into a non-split prion-tangle with the given prion-tangles contained by a one-crossing change. We also determine for every $n>1$ that the minimal crossing number of $n$-string non-split prion-tangles is $2n$ or $2n-2$, respectively, according to whether or not we count the assumption that the loop system is a trivial link. 103-1-9/TopologyofPrionProteins.pdf