title: [Effects of transporter Agp1p ubiquitination on nitrogen utilization in Saccharomyces cerevisiae].
abstract: OBJECTIVE
  The purpose of this work is to studythe effects of ubiquitination of key nitrogen transporter Agp1p on nitrogen utilization in Saccharomyces cerevisiae.
  
  
  METHODS
  The ubiquitination detection vector to examine the ubiquitination process of Agp1p was constructed based on the bimolecular fluorescence complementation technology. The site-directed mutagenesis on the potential ubiquitination sites were performed to verify the effect on its ubiquitination regulation and nitrogen utilization.
  
  
  RESULTS
  Agp1p can be ubiquitinated on the medium with glutamine, arginine, proline or ammonium. The fluorescence levels of mutant strains were down-regulated compared to the wild type strain. The quadruple mutant Agp1pK11-14-98-112R achieved the lowest level among all strains. The ubiuitination process could be significantly repressed by removing the potential ubiquitination residues. Furthermore, flask-shaking experiments with nineamino acids or urea as sole nitrogen source showed that the effect of nitrogen utilization efficiencyinthe quadruple mutant was the highest.
  
  
  CONCLUSIONS
  Ubiquitination was involved in the regulation of Agp1p. Site-directed mutagenesis of potential ubiquitination sites of the transporter could significantly affect the nitrogen utilization process by altering the ubiquitination process.
authors.forename: Yingyu
authors.initials: Y
authors.lastname: Li
authors.forename: Yongkun
authors.initials: Y
authors.lastname: Lv
authors.forename: Jingwen
authors.initials: J
authors.lastname: Zhou
authors.forename: Guocheng
authors.initials: G
authors.lastname: Du
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D020816:Amino Acid Motifs; D026921:Amino Acid Transport Systems, Neutral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: C420623:AGP1 protein, S cerevisiae; D026921:Amino Acid Transport Systems, Neutral; D029701:Saccharomyces cerevisiae Proteins; D009584:Nitrogen