title: Proteomic analyses reveal common promiscuous patterns of cell surface proteins on human embryonic stem cells and sperms.
abstract: BACKGROUND
  It has long been proposed that early embryos and reproductive organs exhibit similar gene expression profiles. However, whether this similarity is propagated to the protein level remains largely unknown. We have previously characterised the promiscuous expression pattern of cell surface proteins on mouse embryonic stem (mES) cells. As cell surface proteins also play critical functions in human embryonic stem (hES) cells and germ cells, it is important to reveal whether a promiscuous pattern of cell surface proteins also exists for these cells.
  
  
  RESULTS
  Surface proteins of hES cells and human mature sperms (hSperms) were purified by biotin labelling and subjected to proteomic analyses. More than 1000 transmembrane or secreted cell surface proteins were identified on the two cell types, respectively. Proteins from both cell types covered a large variety of functional categories including signal transduction, adhesion and transporting. Moreover, both cell types promiscuously expressed a wide variety of tissue specific surface proteins, and some surface proteins were heterogeneously expressed.
  
  
  CONCLUSIONS
  Our findings indicate that the promiscuous expression of functional and tissue specific cell surface proteins may be a common pattern in embryonic stem cells and germ cells. The conservation of gene expression patterns between early embryonic cells and reproductive cells is propagated to the protein level. These results have deep implications for the cell surface signature characterisation of pluripotent stem cells and germ cells and may lead the way to a new area of study, i.e., the functional significance of promiscuous gene expression in pluripotent and germ cells.
authors.affiliation: The Institute of Genetics, College of Life Sciences, Zhejiang University, Hangzhou, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Gu
authors.forename: Jiarong
authors.initials: J
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Wu
authors.forename: Xinzong
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Tan
authors.forename: Yuanji
authors.initials: Y
authors.lastname: Lin
authors.forename: Xiao
authors.initials: X
authors.lastname: Huang
authors.forename: Liangbiao
authors.initials: L
authors.lastname: Chen
authors.forename: Kangshou
authors.initials: K
authors.lastname: Yao
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism*; D053595:Embryonic Stem Cells / Q000166:cytology*; D005720:Gamma Rays; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008024:Ligands; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D040901:Proteomics / Q000379:methods*; D012661:Semen / Q000378:metabolism; D015398:Signal Transduction; D012984:Software
chemical_list: D008024:Ligands; D008565:Membrane Proteins