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NameMr. Reza Esmaeeli
Organization or InstitutionUniversity of Florida
TopicPhysical Chemistry

Mutation and Temperature Sensitivity of Protein Subunit of Ribonuclease P


Reza Esmaeeli, Ben Andal, Loc Huynh, Michael Harris, Alberto Perez

Author Institution(s)

Department of Chemistry, University of Florida


Ribonuclease P (RNase P) is an endoribonuclease responsible for posttranscriptional processing of various RNA transcripts. It is primarily involvedin the maturation process of tRNA by splicing the 5’ leader intron from apremature tRNA. RNase P is comprised of a large catalytic RNA and a smallprotein subunit (P protein). The holoenzyme is functional at 30°C as well as43°C. However, a specific Arg -> His mutation in the P protein diminishes itsactivity only at the higher temperature of 43°C. Here we employ a moleculardynamics approach followed by principal component analysis (PCA) andother computational methods to investigate the impact of mutation ontemperature sensitivity of four P proteins from Escherichia coli, Bacillussubtilis, Staphylococcus aureus and Thermotoga maritima. The choice ofmesophile and thermophile organisms could also shed light on howadaptation to warmer environments is manifest in RNase P. Structural datawere generated from 40μs of molecular dynamics simulations of wild typeand mutant P proteins at both temperatures. Initial results show markedvariation in structural integrity of the proteins due to mutation or hightemperature. The mutant P protein exhibits distinct dynamics and motions asobserved via PCA which provide insights into its temperature sensitivity.