title: Molecular cloning and functional analysis of ESGP, an embryonic stem cell and germ cell specific protein.
abstract: Several putative Oct-4 downstream genes from mouse embryonic stem (ES) cells have been identified using the suppression-subtractive hybridization method. In this study, one of the novel genes encoding an ES cell and germ cell specific protein (ESGP) was cloned by rapid amplification of cDNA ends. ESGP contains 801 bp encoding an 84 amino acid small protein and has no significant homology to any known genes. There is a signal peptide at the N-terminal of ESGP protein as predicted by SeqWeb (GCG) (SeqWeb version 2.0.2, http://gcg.biosino.org:8080/). The result of immunofluorescence assay suggested that ESGP might encode a secretory protein. The expression pattern of ESGP is consistent with the expression of Oct-4 during embryonic development. ESGP protein was detected in fertilized oocyte, from 3.5 day postcoital (dpc) blastocyst to 17.5 dpc embryo, and was only detected in testis and ovary tissues in adult. In vitro, ESGP was only expressed in pluripotent cell lines, such as embryonic stem cells, embryonic caoma cells and embryonic germ cells, but not in their differentiated progenies. Despite its specific expression, forced expression of ESGP is not indispensable for the effect of Oct-4 on ES cell self-renewal, and does not affect the differentiation to three germ layers.
authors.affiliation: Laboratory of Molecular and Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China. chenym@sibs.ac.cn
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Chen
authors.forename: Zhong-Wei
authors.initials: ZW
authors.lastname: Du
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D005854:Germ Cells / Q000378:metabolism*; D051907:Lysosomal Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D052118:Lysosomal-Associated Membrane Protein 1
chemical_list: D051907:Lysosomal Membrane Proteins; C052255:Lamp1 protein, mouse; D052118:Lysosomal-Associated Membrane Protein 1