title: Molecular characterization of the cold- and heat-induced Arabidopsis PXL1 gene and its potential role in transduction pathways under temperature fluctuations.
abstract: LRR-RLK (Leucine-Rich Repeat Receptor-Like Kinase) proteins are believed to play essential roles in cell-to-cell communication during various cellular processes including development, hormone perception, and abiotic stress responses. We isolated an LRR-RLK gene previously named Arabidopsis PHLOEM INTERCALATED WITH XYLEM-LIKE 1 (AtPXL1) and examined its expression patterns. AtPXL1 was highly induced by cold and heat stress, but not by drought. The fluorescence signal of 35S::AtPXL1-EGFP was closely localized to the plasma membrane. A yeast two-hybrid and bimolecular fluorescence complementation assay exhibited that AtPXL1 interacts with both proteins, A. thaliana histidine-rich dehydrin1 (AtHIRD1) and A. thaliana light-harvesting protein complex I (AtLHCA1). We found that AtPXL1 possesses autophosphorylation activity and phosphorylates AtHIRD1 and AtLHCA1 in an in vitro assay. Subsequently, we found that the knockout line (atpxl1) showed hypersensitive phenotypes when subjected to cold and heat during the germination stage, while the AtPXL1 overexpressing line as well as wild type plants showed high germination rates compared to the knockout plants. These results provide an insight into the molecular function of AtPXL1 in the regulation of signal transduction pathways under temperature fluctuations.
authors.affiliation: Plant Genomics Laboratory, Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea.
authors.forename: Chang Gyo
authors.initials: CG
authors.lastname: Jung
authors.affiliation: Plant Genomics Laboratory, Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea.
authors.forename: Sun-Goo
authors.initials: SG
authors.lastname: Hwang
authors.affiliation: Plant Genomics Laboratory, Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea.
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Park
authors.affiliation: Plant Genomics Laboratory, Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea.
authors.forename: Hyeon Mi
authors.initials: HM
authors.lastname: Park
authors.affiliation: Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Singjeong, Jeongeup 580-185, Jeonbuk, Republic of Korea.
authors.forename: Dong Sub
authors.initials: DS
authors.lastname: Kim
authors.affiliation: Department of Applied Biology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea.
authors.forename: Duck Hwan
authors.initials: DH
authors.lastname: Park
authors.affiliation: Plant Genomics Laboratory, Department of Applied Plant Sciences, Kangwon National University, Chuncheon 200-713, Republic of Korea. Electronic address: csjang@kangwon.ac.kr.
authors.forename: Cheol Seong
authors.initials: CS
authors.lastname: Jang
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D003080:Cold Temperature; D003198:Computer Simulation; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018525:Germination; D006358:Hot Temperature; D010766:Phosphorylation; D010802:Phylogeny; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases; D021381:Protein Transport; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics*; D013312:Stress, Physiological / Q000235:genetics; D013347:Subcellular Fractions / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D029681:Arabidopsis Proteins; D020794:Receptor Protein-Tyrosine Kinases; C000604254:PXL1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases
keywords: Abiotic stress; Co-expression network; Germination; Leucine-rich repeat receptor-like kinase; Protein–protein interaction