[1P-1] Poster 1 (1P-01ー1P-48)

[1P-46*] A Novel Score for Capturing Features of Intrinsically Disordered Regions Using Statistical Model

^○Hayato Aida^1,2,3, Ryuhei Harada², Yasuteru Shigeta², Kentaro Tomii¹ (1.AIRC, AIST, 2.CCS, Univ. of Tsukuba, 3.Degree Programs in Life and Earth Sci., Univ. of Tsukuba)

Phase separation of proteins and nucleic acids has been observed in many biological systems. Particularly, intrinsically disordered regions (IDRs) in proteins are often necessary for modulating intracellular phase separation. A recent study has shown that the valence and patterning of aromatic residues in IDRs can modulate intracellular phase separation. In the report, they used a parameter Ω_aro to quantify patterning of aromatic residues, regarded as “stickers”. However, because Ω_aro is sensitive to the amino acid composition of IDRs, Ω_aro is not always appropriate to quantify the patterning of stickers in IDRs. Based on that study, we proposed a novel score, that is independent of amino acid composition, to evaluate the distribution of aromatic residues in IDRs. To calculate the score, which we call BS-score, we regarded the sequence of IDRs as sticks broken by aromatic residues and applied the statistical model called broken-stick model. We calculated the scores for IDRs in proteins that cause phase separation, and found that aromatic residues were more uniformly dispersed as the content ratio of aromatic residues increased.