title: Evaluation of in vitro spermatogenesis system effectiveness to study genes behavior: monitoring the expression of the testis specific 10 (Tsga10) gene as a model.
abstract: BACKGROUND
  In vitro generation of germ cells introduces a novel approach to male infertility and provides an effective system in gene tracking studies, however many aspects of this process have remained unclear. We aimed to promote mouse embryonic stem cells (mESC) differentiation into germ cells and evaluate its effectiveness with tracking the expression of the Tsga10 during this process.
  
  
  METHODS
  mESCs were differentiated into germ cells in the presence of Retinoic Acid. Based on developmental schedule of the postnatal testis, samples were taken on the 7th, 12th, and 25th days of the culture and were subjected to expression analysis of a panel of germ cell specific genes. Expression of Tsga10 in RNA and protein levels was then analyzed.
  
  
  RESULTS
  Transition from mitosis to meiosis occurred between 7th and 12th days of mESC culture and post-meiotic gene expression did not occur until the 25th day of the culture. Results showed low level of Tsga10expression in undifferentiated stem cells. During transition from meiotic to post-meiotic phase, Tsga10 expression increased in 6.6 folds. This finding is in concordance with in vivo changes during transition from pre-pubertal to pubertal stage. Localization of processed and unprocessed forms of the related protein was similar to those in vivo as well.
  
  
  CONCLUSIONS
  Expression pattern of Tsga10, as a gene with critical function in spermatogenesis, is similar during in vitro and in vivo germ cell generation. The results suggest that in vitro derived germ cells could be a trusted model to study genes behavior during spermatogenesis.
authors.affiliation: 1)Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2)Department of Medical Genetics, School of Medicine, Tehran university of Medical Sciences, Tehran, Iran.modaresi@tums.ac.ir.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Miryounesi
authors.affiliation: GENEOCELL, Advanced Molecular and Cellular Technologies, Montreal, Canada.
authors.forename: Karim
authors.initials: K
authors.lastname: Nayernia
authors.affiliation: 2)Department of Medical Genetics, School of Medicine, Tehran university of Medical Sciences, Tehran, Iran. 4)Cancer Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam Beigom
authors.initials: MB
authors.lastname: Mobasheri
authors.affiliation: Department of Medical Genetics, School of Medicine, Shiraz university of Medical Sciences, Shiraz, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Dianatpour
authors.affiliation: Departments of Anatomy and Cell Biology, Queen's University, 9th Floor, Botterell Hall, Kingston, Ontario, Canada K7L 3N6.
authors.forename: Richard
authors.initials: R
authors.lastname: Oko
authors.affiliation: Kamali Hospital, Alborz University of Medical Sciences, Karaj, Iran.
authors.forename: Shahram
authors.initials: S
authors.lastname: Savad
authors.affiliation: Department of Medical Genetics, School of Medicine, Tehran university of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Modarressi
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003598:Cytoskeletal Proteins; D053595:Embryonic Stem Cells / Q000502:physiology; D005786:Gene Expression Regulation / Q000235:genetics* / Q000502:physiology; D066298:In Vitro Techniques / Q000379:methods; D008297:Male; D008540:Meiosis / Q000235:genetics / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008938:Mitosis / Q000235:genetics / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction; D029589:Seminal Plasma Proteins / Q000096:biosynthesis* / Q000235:genetics; D013091:Spermatogenesis / Q000235:genetics* / Q000502:physiology; D013737:Testis / Q000166:cytology / Q000378:metabolism / Q000502:physiology
chemical_list: D003598:Cytoskeletal Proteins; D029589:Seminal Plasma Proteins; C493239:Tsga10 protein, mouse