title: Heterotrimeric G Stimulatory Protein α Subunit Is Required for Intestinal Smooth Muscle Contraction in Mice.
abstract: The α subunit of the heterotrimeric G stimulatory protein (Gsa), encoded by the guanine nucleotide binding protein, α-stimulating gene (Gnas, in mice), is expressed ubiquitously and mediates receptor-stimulated production of cyclic adenosine monophosphate and activation of the protein kinase A signaling pathway. We investigated the roles of Gsa in vivo in smooth muscle cells of mice.
  
  
  
  We performed studies of mice with Cre recombinase-mediated disruption of Gnas in smooth muscle cells (GsaSMKOand SM22-CreERT2, induced in adult mice by tamoxifen). Intestinal tissues were collected for histologic, biochemical, molecular, cell biology, and physiology analyses. Intestinal function was assessed in mice using the whole-gut transit time test. We compared gene expression patterns of intestinal smooth muscle from mice with vs without disruption of Gnas. Biopsy specimens from ileum of patients with chronic intestinal pseudo-obstruction and age-matched control biopsies were analyzed by immunohistochemistry.
  
  
  
  Disruption of Gnas in smooth muscle of mice reduced intestinal motility and led to death within 4 weeks. Tamoxifen-induced disruption of Gnas in adult mice impaired contraction of intestinal smooth muscle and peristalsis. More than 80% of these died within 3 months of tamoxifen exposure, with features of intestinal pseudo-obstruction characterized by chronic intestinal dilation and dysmotility. Gsa deficiency reduced intestinal levels of cyclic adenosine monophosphate and transcriptional activity of the cyclic adenosine monophosphate response element binding protein 1 (CREB1); this resulted in decreased expression of the forkhead box F1 gene (Foxf1) and protein, and contractile proteins, such as myosin heavy chain 11; actin, α2, smooth muscle, aorta; calponin 1; and myosin light chain kinase. We found decreased levels of Gsa, FOXF1, CREB1, and phosphorylated CREB1 proteins in intestinal muscle layers of patients with chronic intestinal pseudo-obstruction, compared with tissues from controls.
  
  
  
  Gsa is required for intestinal smooth muscle contraction in mice, and its levels are reduced in ileum biopsies of patients with chronic intestinal pseudo-obstruction. Mice with disruption of Gnas might be used to study human chronic intestinal pseudo-obstruction.
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China.
authors.forename: Xiaoteng
authors.initials: X
authors.lastname: Qin
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China; Key Laboratory of the Ministry of Education for Experimental Teratology, Department of Histology and Embryology, Shandong University School of Medicine, Jinan, China.
authors.forename: Shangming
authors.initials: S
authors.lastname: Liu
authors.affiliation: Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Qiulun
authors.initials: Q
authors.lastname: Lu
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China.
authors.forename: Xiuxin
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of General Surgery, Qilu Hospital of Shandong University, Jinan, China.
authors.forename: Sanyuan
authors.initials: S
authors.lastname: Hu
authors.affiliation: Department of Physiology, School of Medicine, Shandong University, Jinan, China.
authors.forename: Jingxin
authors.initials: J
authors.lastname: Li
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.affiliation: School of Life Science and Key Laboratory of the Ministry of Education for Experimental Teratology, Shandong University, Jinan, China.
authors.forename: Jiangang
authors.initials: J
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center and MOE Key Laboratory of Model Animal for Disease Study, Nanjing University, Nanjing, China.
authors.forename: Min-Sheng
authors.initials: MS
authors.lastname: Zhu
authors.affiliation: Interfakultäres Institut für Biochemie (IFIB), Signaltransduktion - Transgene Modelle, Universität Tübingen, Tübingen, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Feil
authors.affiliation: ATCG Cancer Center, ATCG Corporation Ltd, Suzhou, China.
authors.forename: Huashun
authors.initials: H
authors.lastname: Li
authors.affiliation: Metabolic Diseases Branch, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.affiliation: Metabolic Diseases Branch, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland.
authors.forename: Lee S
authors.initials: LS
authors.lastname: Weinstein
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China. Electronic address: zhangyun@sdu.edu.cn.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, China. Electronic address: zhangwencheng@sdu.edu.cn.
authors.forename: Wencheng
authors.initials: W
authors.lastname: Zhang
mesh_terms: D000199:Actins / Q000378:metabolism; D000328:Adult; D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002864:Chromogranins / Q000235:genetics* / Q000378:metabolism; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics* / Q000378:metabolism; D005769:Gastrointestinal Motility / Q000235:genetics*; D020962:Heterotrimeric GTP-Binding Proteins; D006801:Humans; D007082:Ileum / Q000378:metabolism; D019426:Integrases; D007418:Intestinal Pseudo-Obstruction / Q000378:metabolism*; D007422:Intestines / Q000502:physiology*; D008297:Male; D051379:Mice; D008840:Microfilament Proteins / Q000378:metabolism; D008875:Middle Aged; D009119:Muscle Contraction / Q000235:genetics*; D009130:Muscle, Smooth / Q000502:physiology*; D018995:Myosin Heavy Chains / Q000378:metabolism; D009219:Myosin-Light-Chain Kinase / Q000378:metabolism; D000096985:Calponins
chemical_list: D000199:Actins; D002135:Calcium-Binding Proteins; D002864:Chromogranins; D017362:Cyclic AMP Response Element-Binding Protein; D051858:Forkhead Transcription Factors; D019205:GTP-Binding Protein alpha Subunits, Gs; D020962:Heterotrimeric GTP-Binding Proteins; D019426:Integrases; D008840:Microfilament Proteins; D018995:Myosin Heavy Chains; D009219:Myosin-Light-Chain Kinase; D000096985:Calponins; C558396:Acta2 protein, mouse; C115163:CREB1 protein, human; C492004:Creb1 protein, mouse; C098521:FOXF1 protein, human; C486293:Foxf1 protein, mouse; C045073:Cre recombinase; C406732:GNAS protein, human; C498642:Gnas protein, mouse
keywords: CIP; Digestion; Intestine; Mouse Model