title: Contribution of RNA polymerase concentration variation to protein expression noise.
abstract: Cell-to-cell variation in gene expression, or noise, is a general phenomenon observed within cell populations. Transcription is known to be the key stage of gene expression where noise is generated, however, how variation in RNA polymerase (RNAP) concentration contributes to gene expression noise is unclear. Here, we quantitatively investigate how variations in absolute amounts of RNAP molecules affect noise in the expression of two fluorescent protein reporters driven by identical promoters. We find that intrinsic noise is independent of variation in RNAP concentrations, whereas extrinsic noise, which is variation in gene expression due to varying cellular environments, scales linearly with variation in RNAP abundance. Specifically, the propagation of RNAP abundance variation to expressed protein noise is inversely proportional to the concentration of RNAP, which suggests that the change in noise that results from RNAP fluctuations is determined by the fraction of promoters that is not occupied by RNAP.
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Sora
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Seunghyeon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 156-756, Korea.
authors.forename: Yu
authors.initials: Y
authors.lastname: Rim Lim
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Cheolhee
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Hyeong Jeon
authors.initials: HJ
authors.lastname: An
authors.affiliation: Department of Chemistry and Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 156-756, Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 156-756, Korea.
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Sung
authors.affiliation: 1] Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea [2] School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Nam Ki
authors.initials: NK
authors.lastname: Lee
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D000097573:Red Fluorescent Protein
chemical_list: D012321:DNA-Directed RNA Polymerases; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D014764:Viral Proteins; D000097573:Red Fluorescent Protein; C485182:Cyan Fluorescent Protein; C062210:bacteriophage T7 RNA polymerase