title: Proteomic identification of differentially expressed and phosphorylated proteins in epidermis involved in larval-pupal metamorphosis of Helicoverpa armigera.
abstract: BACKGROUND
  Metamorphosis is an important process in the life cycle of holometabolous insects and is regulated by insect hormones. During metamorphosis, the epidermis goes through a significant transformation at the biochemical and molecular levels.
  
  
  RESULTS
  To identify proteins and phosphoproteins involved in this process, we separated and compared epidermal protein profiles between feeding larvae and metamorphically committed larvae using two-dimensional gel electrophoresis and Pro-Q Diamond Phosphoprotein Staining. Sixty-one spots showing differential expression and/or phosphorylation were analyzed by mass spectrometry and eighteen proteins were proved related to larval-pupal transformation. Eight of them were further examined at the mRNA level by Reverse Transcription Polymerase Chain Reaction (RT-PCR) and two of them were examined at the protein level by Western blot. Calponin was highly expressed in the metamorphic epidermis and phosphorylated by protein kinase C.
  
  
  CONCLUSIONS
  Our results suggest that the expression and phosphorylation of these proteins may play important roles in coordinating the biochemical processes involved in larval-pupal metamorphosis.
authors.affiliation: School of Life Sciences, the Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, Shandong University, Jinan, 250100, PR China. qfu4@wisc.edu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.forename: Peng-Cheng
authors.initials: PC
authors.lastname: Liu
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Wang
authors.forename: Qi-Sheng
authors.initials: QS
authors.lastname: Song
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004817:Epidermis / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D007814:Larva / Q000235:genetics; D008675:Metamorphosis, Biological; D008840:Microfilament Proteins / Q000378:metabolism; D009036:Moths / Q000235:genetics*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D020543:Proteome / Q000235:genetics*; D040901:Proteomics; D011679:Pupa / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053719:Tandem Mass Spectrometry; D000096985:Calponins
chemical_list: D002135:Calcium-Binding Proteins; D008840:Microfilament Proteins; D011493:Protein Kinase C; D020543:Proteome; D000096985:Calponins