human embryonic stem cells

Mouse interleukin-15 receptor subunit alpha, also known as Il15ra, is a high-affinity receptor for interleukin-15. Il15ra associates as a heterotrimer with the IL-2 receptor beta and gamma subunits (Common gamma chain, or gamma c) to initiate signal transduction. It can signal both in cis and trans where IL15R from one subset of cells presents IL15 to neighboring IL2RG-expressing cells. Il15ra is expressed in special cells including a wide variety of Tand B cells and non-lymphoid cells. Human Il15ra shares 45% amino acid sequence homology with the mouse form of the receptor. Eight isoforms of IL-15 R alpha mRNA have been identified, resulting from alternative splicing events involving different exons.

Interleukin 15 Receptor alpha (IL-15Rα) is a transmembrane glycoprotein that plays a pleiotropic role in immune development and function, including the positive maintenance of lymphocyte homeostasis. IL-15Rα chain can bind soluble IL-15 and “transpresent” cytokine to the cells, allowing them to respond to IL-15. Soluble IL-15Rα can function as a specific high-affinity IL-15 antagonist. The soluble IL-15/IL-15Rα complexes exhibit a strong agonistic activity which is mediated through membrane-bound IL-15 receptor β and γ heterodimers and enables signaling to cells.

Noggin is a secreted homodimeric glycoprotein that is an antagonist of bone morphogenetic proteins (BMPs). Mouse Noggin cDNA encodes a 232 amino acid (aa) residue precursor protein with 19 aa residue putative signal peptide that is cleaved to generate the 213 aa residue mature protein which is secreted as a homodimeric glycoprotein. Secreted Noggin probably remains close to the cell surface due to its binding of heparin-containing proteoglycans. Noggin binds some BMPs such as BMP4 with high affinity and others such as BMP7 with lower affinity. It antagonizes BMP bioactivities by blocking epitopes on BMPs that are needed for binding to both type I and type II receptors. Noggin is expressed in defined areas of the adult central nervous system and peripheral tissues such as lung, skeletal muscle and skin. During culture of human embryonic stem cells (hESC) or neural stem cells under certain conditions, addition of Noggin to antagonize BMP activity may allow stem cells to proliferate while maintaining their undifferentiated state, or alternatively, to differentiate into dopaminergic neurons.

Transcription factor that binds DNA in a non-specific manner, yet also specifically recognizes the core sequence 5'-CAC[GA]TG-3'. Activates the transcription of growth-related genes. Binds to the VEGFA promoter, promoting VEGFA production and subsequent sprouting angiogenesis. Regulator of somatic reprogramming, controls self-renewal of embryonic stem cells. Functions with TAF6L to activate target gene expression through RNA polymerase II pause release. c-Myc Protein, Human, Recombinant (Avi & His & MBP), Biotinylated is expressed in E. coli expression system with N-MBP and C-6xHis-Avi tag. The predicted molecular weight is 96.6 kDa and the accession number is P01106.

B7-H5, also known as VISTA , B7H5, Dies1, SISP1 and C10orf54, is a 55-65 kDa member of the Ig superfamily. It is a transmembrane molecule expressed in bone, on embryonic stem cells (ESCs), and on tumor cell surfaces. B7-H5/Gi24/VISTA Protein, Human, Recombinant (hFc) is expressed in HEK293 mammalian cells with C-hFc tag. The predicted molecular weight is 44.9 kDa and the accession number is Q9H7M9.

B7-H5, also known as VISTA , B7H5, Dies1, SISP1 and C10orf54, is a 55-65 kDa member of the Ig superfamily. It is a transmembrane molecule expressed in bone, on embryonic stem cells (ESCs), and on tumor cell surfaces. B7-H5/Gi24/VISTA Protein, Human, Recombinant (His) is expressed in HEK293 mammalian cells with C-His tag. The predicted molecular weight is 19 kDa and the accession number is Q9H7M9.

Transcription factor that binds DNA in a non-specific manner, yet also specifically recognizes the core sequence 5'-CAC[GA]TG-3'. Activates the transcription of growth-related genes. Binds to the VEGFA promoter, promoting VEGFA production and subsequent sprouting angiogenesis. Regulator of somatic reprogramming, controls self-renewal of embryonic stem cells. Functions with TAF6L to activate target gene expression through RNA polymerase II pause release. c-Myc Protein, Human, Recombinant (His) is expressed in E. coli expression system with N-6xHis tag. The predicted molecular weight is 52.8 kDa and the accession number is P01106.

Ligand for members of the frizzled family of seven transmembrane receptors. Functions in the canonical Wnt signaling pathway that results in activation of transcription factors of the TCF/LEF family. Required for normal embryonic mesoderm development and formation of caudal somites. Required for normal morphogenesis of the developing neural tube. Mediates self-renewal of the stem cells at the bottom on intestinal crypts (in vitro). Wnt3a Protein, Human, Recombinant (His) is expressed in E. coli expression system with N-6xHis tag. The predicted molecular weight is 41.3 kDa and the accession number is P56704.

Fibroblast growth factor 4(FGF-4) is a heparin binding member of the FGF family. The human FGF4 cDNA encodes 206 amino acids (aa) with a 33 aa signal sequence and a 173 aa mature protein with an FGF homology domain that contains a heparin binding region near the C-terminus. Mature human FGF4 shares 91%, 82%, 94% and 91% aa identity with mouse, rat, canine and bovine FGF4, respectively. Human FGF-4 has been shown to exhibit cross species activity. Expression of FGF-4 and its receptors, FGF R1c, 2c, 3c and 4, is spatially and temporally regulated during embryonic development. FGF-4 is proposed to play a physiologically relevant role in human embryonic stem cell selfrenewal. It promotes stem cell proliferation, but may also aid differentiation depending on context and concentration, and is often included in embryonic stem cell media in vitro. FGF-4 is mitogenic for fibroblasts and endothelial cells in vitro and has autocrine transforming potential. It is a potent angiogenesis promoter in vivo and has been investigated as therapy for coronary artery disease.

Human acyl-coenzyme A binding domain-containing member 6 (ACBD6) is a modular protein that carries an acyl-CoA binding domain at its N terminus and two ankyrin motifs at its C terminus. In mammals, there are six members of the acyl-CoA binding domain-containing (ACBD) family, and their annotation is not uniform. All six ACBD proteins contain an ACB domain at the N terminus, but they do not share significant homology at the C-terminal region. ACBD6 is a 32 kDa protein that is predicted by sequence analysis to carry an ACB domain between residues 42 and 125 and two ANK motifs at its C terminus. This protein binds long-chain acyl-CoAs with a strong preference for unsaturated, C18:1-CoA and C20:4-CoA, over saturated, C16:0-CoA, acyl species. ACBD6 is not a ubiquitous protein, but it is expressed in hematopoietic tissues and appears to be restricted to primitive stem cells present in those tissues with functions in blood and vessel development. ACBD6 was detected in bone marrow, spleen, placenta, cord blood, circulating CD34+ progenitors, and embryonic-like stem cells derived from placenta. In placenta, the protein was only detected in CD34+ progenitor cells present in blood and CD31+ endothelial cells surrounding the blood vessels. These cells were also positive for the marker CD133, and they probably constitute hemangiogenic stem cells, precursors of both blood and vessels. We propose that human ACBD6 represents a cellular marker for primitive progenitor cells with functions in hematopoiesis and vascular endothelium development.