title: Arabidopsis CAP1-mediated ammonium sensing required reactive oxygen species in plant cell growth.
abstract: [Ca(2+)]cyt-associated protein kinase (CAP) gene 1 is a receptor-like kinase that belongs to CrRLK1L (Catharanthus roseus Receptor like kinase) subfamily. CAP1 has been identified as a novel modulator of NH4(+) in the tonoplast, which regulates root hair growth by maintaining the cytoplasmic Ca(2+) gradients. Different expression pattern of tonoplast intrinsic protein (TIP2;3) in the CAP1 knock out mutant and wild type on Murashige and Skoog (MS) medium suggested that CAP1 influences transport activity to regulate the compartmentalization of NH4(+) into vacuole. Lower expression level of Oxidative Signal-Inducible1(OXI1) in the cap1-1 root and the abnormal reactive oxygen species (ROS) gradient in root hair of cap1-1 on MS medium indicated that ROS signaling involve in CAP1-regulated root hair growth. Wild-type-like ROS distribution pattern in the cap1-1 root hair can be reestablished in seedlings grown on NH4(+) deficient medium, which indicated that CAP1 functions as a sensor for NH4(+) signaling in maintaining tip-focused ROS gradient in root hairs polar growth.
authors.affiliation: a Institute of Plant Stress Biology; State Key Laboratory of Cotton Biology; Department of Biology; Henan University; PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Bai
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Ma
authors.forename: Lijie
authors.initials: L
authors.lastname: Gao
authors.forename: Chun-Peng
authors.initials: CP
authors.lastname: Song
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism*; D017360:Arabidopsis / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism; D018519:Meristem / Q000254:growth & development / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D059828:Plant Cells / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings; D015398:Signal Transduction; D014617:Vacuoles / Q000378:metabolism
chemical_list: D064751:Ammonium Compounds; D029681:Arabidopsis Proteins; D017382:Reactive Oxygen Species; D011494:Protein Kinases; D009584:Nitrogen; D002118:Calcium
keywords: CAP1; CrRLK1L; ROS; Root hair; ammonium sensing