computational-biology-2018-posters-abstracts

5 / 14

Page 37
Notes:
conferenceseries.com
Volume 11 Journal of Proteomics & Bioinformatics Open Access Computational Biology 2018
September 05-06, 2018
September 05-06, 2018 Tokyo, Japan
International Conference on
Computational Biology and Bioinformatics
Yuki Sasahara et al., J Proteomics Bioinform 2018, Volume 11
DOI: 10.4172/0974-276X-C1-113
Mathematical exploration of selective pressures that shaped themetabolic zonation of livernitrogenmetabolism
Yuki Sasahara, Yasuhiro Naito and Masaru Tomita
Keio University, Japan
As ammonia which is one of the simplest nitrogen compounds is toxic for the central nervous system, its blood concentration
should be maintained at low level. Human excrete most of nitrogen as urea in urine and urea synthesis exclusively occurs
in liver. Ammonia is an inescapable metabolic intermediate during urea synthesis from various nitrogen compounds in
hepatocytes. Most of ammonia is produced in hepatocytes and many of it is converted into urea and the rest is converted into
reusable glutamine. The human liver is super-parallel metabolic filter with approximately 500,000 hepatic lobules that consist
of approximately 500,000 hepatocytes. Blood flows into a hepatic lobule from fine branches of hepatic artery and portal vein
and goes out from central vein. While upstream (periportal, PP) blood abundantly contains external molecules absorbed
in the gastrointestinal tract, downstream (perivenous, PV) blood carries almost adjusted substances. Therefore, metabolic
heterogeneity inevitably arises between PP and PV. Moreover, it is known that many enzymes heterogeneously express between
PP and PV. Such heterogeneity is called metabolic zonation. For nitrogen metabolism, activity of urea cycle is dominant in PP
and Glutamine Synthase (GS) activity is confined in PV. Recently, it is shown that hepatic GS deficient transgenic mice exhibit
hyperammonemia and some organs other than liver affect its pathophysiology. In this study, we made the nitrogen homeostasis
model of the whole body which incorporated metabolic zonation and tried to represent the systematic condition of nitrogen
metabolism found in the GS deficient mice.
Biography
Yuki Sasahara is a undergraduate student of department of environment and information studies of Keio University. She is expected to earn B.A.(Environment and
Information Studies) in Mar.2019. She graduated Ferris Girls' Senior High School and entered Keio University in 2015. She has joined the E-Cell project and majors
in computational biology at the institute for advanced biosciences of Keio University.