title: Gene expression profiles and phosphorylation patterns of AMP-activated protein kinase subunits in various mesenchymal cell types.
abstract: BACKGROUND
  Recent studies on bone have shown an endocrine role of the skeleton, which could be impaired in various human diseases, including osteoporosis, obesity, and diabetes-associated bone diseases. As a sensor and regulator of energy metabolism, AMP-activated protein kinase (AMPK) may also play an important role in the regulation of bone metabolism. The current study aimed to establish the expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types.
  
  
  METHODS
  Reverse transcription-polymerase chain reaction (PCR) for relative quantification, real-time PCR for absolute quantification, and Western blotting were used to investigate the gene expression profiles and phosphorylation patterns of AMPK subunits in several mesenchymal cell types, including primary human mesenchymal stem cells (hMSCs) and hFOB, Saos-2, C3H/10T1/2, MC3T3-E1, 3T3-L1, and C2C12 cells.
  
  
  RESULTS
  AMPKα1 and AMPKβ1 mRNAs were abundantly expressed in all cell types. AMPKγ1 mRNA was abundantly expressed in C3H/10T1/2, MC3T3-E1, 3T3-L1, and C2C12 but not detected in human-derived cell types. AMPKγ2 mRNA was mildly expressed in all cell types. AMPKα1 protein was highly expressed in all cell types and AMPKα2 protein was highly expressed only in hFOB and Saos-2 cells. AMPKβ1 protein was abundantly expressed in all cell types except for Saos-2, in which AMPKβ2 protein overwhelmed AMPKβ1 expression. AMPKγ1 and AMPKγ2 proteins were expressed in C3H/10T1/2, MC3T3-E1, 3T3-L1, and C2C12 cells and only AMPKγ2 protein was expressed in hMSCs, hFOB and Saos-2 cells. AMPKα was phosphorylated at Thr172 and Ser485 and AMPKβ1 was phosphorylated at Ser108 and Ser182 in all cell types with a specific pattern in each cell type.
  
  
  CONCLUSIONS
  The combination of AMPK α, β, and γ subunits and phosphorylation of AMPKα (Thr172 and Ser485) and AMPKβ1 (Ser108 and Ser182) showed a specific pattern in each cell type.
authors.affiliation: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, China.
authors.forename: Yugang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, China.
authors.forename: Qiming
authors.initials: Q
authors.lastname: Fan
authors.affiliation: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Ma
authors.affiliation: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Lin
authors.affiliation: Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, China. Email: tingtingtang@hotmail.com.
authors.forename: Tingting
authors.initials: T
authors.lastname: Tang
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000201:enzymology*; D051379:Mice; D010766:Phosphorylation
chemical_list: D055372:AMP-Activated Protein Kinases