Mikkelsen TS et al. ( 2008)
Nature 454 7200 49--55
Dissecting direct reprogramming through integrative genomic analysis
Somatic cells can be reprogrammed to a pluripotent state through the ectopic expression of defined transcription factors. Understanding the mechanism and kinetics of this transformation may shed light on the nature of developmental potency and suggest strategies with improved efficiency or safety. Here we report an integrative genomic analysis of reprogramming of mouse fibroblasts and B lymphocytes. Lineage-committed cells show a complex response to the ectopic expression involving induction of genes downstream of individual reprogramming factors. Fully reprogrammed cells show gene expression and epigenetic states that are highly similar to embryonic stem cells. In contrast,stable partially reprogrammed cell lines show reactivation of a distinctive subset of stem-cell-related genes,incomplete repression of lineage-specifying transcription factors,and DNA hypermethylation at pluripotency-related loci. These observations suggest that some cells may become trapped in partially reprogrammed states owing to incomplete repression of transcription factors,and that DNA de-methylation is an inefficient step in the transition to pluripotency. We demonstrate that RNA inhibition of transcription factors can facilitate reprogramming,and that treatment with DNA methyltransferase inhibitors can improve the overall efficiency of the reprogramming process.
View Publication
Li X et al. (AUG 2015)
Cell stem cell 17 2 195--203
Small-Molecule-Driven Direct Reprogramming of Mouse Fibroblasts into Functional Neurons.
Recently,direct reprogramming between divergent lineages has been achieved by the introduction of regulatory transcription factors. This approach may provide alternative cell resources for drug discovery and regenerative medicine,but applications could be limited by the genetic manipulation involved. Here,we show that mouse fibroblasts can be directly converted into neuronal cells using only a cocktail of small molecules,with a yield of up to textgreater90% being TUJ1-positive after 16 days of induction. After a further maturation stage,these chemically induced neurons (CiNs) possessed neuron-specific expression patterns,generated action potentials,and formed functional synapses. Mechanistically,we found that a BET family bromodomain inhibitor,I-BET151,disrupted the fibroblast-specific program,while the neurogenesis inducer ISX9 was necessary to activate neuron-specific genes. Overall,our findings provide a proof of principle" for chemically induced direct reprogramming of somatic cell fates across germ layers without genetic manipulation�
View Publication
产品类型:
产品号#:
72052
72054
72112
72114
72232
72234
73202
73712
73714
100-1042
100-0249
100-1051
产品名:
CHIR99021
CHIR99021
Forskolin
Forskolin
SB431542 (Hydrate)
SB431542(水合物)
ISX-9
I-BET151
I-BET151
CHIR99021
Forskolin
SB431542(水合物)
Fu J-DD et al. (SEP 2013)
Stem Cell Reports 1 3 235--247
Direct Reprogramming of Human Fibroblasts toward a Cardiomyocyte-like State
Summary Direct reprogramming of adult somatic cells into alternative cell types has been shown for several lineages. We previously showed that GATA4,MEF2C,and TBX5 (GMT) directly reprogrammed nonmyocyte mouse heart cells into induced cardiomyocyte-like cells (iCMs) in vitro and in vivo. However,GMT alone appears insufficient in human fibroblasts,at least in vitro. Here,we show that GMT plus ESRRG and MESP1 induced global cardiac gene-expression and phenotypic shifts in human fibroblasts derived from embryonic stem cells,fetal heart,and neonatal skin. Adding Myocardin and ZFPM2 enhanced reprogramming,including sarcomere formation,calcium transients,and action potentials,although the efficiency remained low. Human iCM reprogramming was epigenetically stable. Furthermore,we found that transforming growth factor β signaling was important for,and improved the efficiency of,human iCM reprogramming. These findings demonstrate that human fibroblasts can be directly reprogrammed toward the cardiac lineage,and lay the foundation for future refinements in vitro and in vivo. textcopyright 2013 The Authors.
View Publication
产品类型:
产品号#:
05850
05857
05870
05875
85850
85857
85870
85875
产品名:
mTeSR™1
mTeSR™1
C. Zou et al. (sep 2005)
Journal of biochemical and biophysical methods 64 3 207--15
2-NBDG as a fluorescent indicator for direct glucose uptake measurement.
Evaluation of glucose uptake ability in cells plays a fundamental role in diabetes mellitus research. In this study,we describe a sensitive and non-radioactive assay for direct and rapid measuring glucose uptake in single,living cells. The assay is based on direct incubation of mammalian cells with a fluorescent d-glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose (2-NBDG) followed by flow cytometric detection of fluorescence produced by the cells. A series of experiments were conducted to define optimal conditions for this assay. By this technique,it was found that insulin lost its physiological effects on cells in vitro meanwhile some other anti-diabetic drugs facilitated the cell glucose uptake rates with mechanisms which likely to be different from those of insulin or those that were generally accepted of each drug. Our findings show that this technology has potential for applications in both medicine and research.
View Publication
产品类型:
产品号#:
100-0546
100-0547
产品名:
2-NBDG
2-NBDG
Hanna J et al. (APR 2008)
Cell 133 2 250--64
Direct reprogramming of terminally differentiated mature B lymphocytes to pluripotency.
Pluripotent cells can be derived from fibroblasts by ectopic expression of defined transcription factors. A fundamental unresolved question is whether terminally differentiated cells can be reprogrammed to pluripotency. We utilized transgenic and inducible expression of four transcription factors (Oct4,Sox2,Klf4,and c-Myc) to reprogram mouse B lymphocytes. These factors were sufficient to convert nonterminally differentiated B cells to a pluripotent state. However,reprogramming of mature B cells required additional interruption with the transcriptional state maintaining B cell identity by either ectopic expression of the myeloid transcription factor CCAAT/enhancer-binding-protein-alpha (C/EBPalpha) or specific knockdown of the B cell transcription factor Pax5. Multiple iPS lines were clonally derived from both nonfully and fully differentiated B lymphocytes,which gave rise to adult chimeras with germline contribution,and to late-term embryos when injected into tetraploid blastocysts. Our study provides definite proof for the direct nuclear reprogramming of terminally differentiated adult cells to pluripotency.
View Publication
产品类型:
产品号#:
72742
产品名:
Doxycycline (Hyclate)
Easley CA et al. (SEP 2012)
Cell reports 2 3 440--6
Direct differentiation of human pluripotent stem cells into haploid spermatogenic cells.
Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) have been shown to differentiate into primordial germ cells (PGCs) but not into spermatogonia,haploid spermatocytes,or spermatids. Here,we show that hESCs and hiPSCs differentiate directly into advanced male germ cell lineages,including postmeiotic,spermatid-like cells,in vitro without genetic manipulation. Furthermore,our procedure mirrors spermatogenesis in vivo by differentiating PSCs into UTF1-,PLZF-,and CDH1-positive spermatogonia-like cells; HIWI- and HILI-positive spermatocyte-like cells; and haploid cells expressing acrosin,transition protein 1,and protamine 1 (proteins that are uniquely found in spermatids and/or sperm). These spermatids show uniparental genomic imprints similar to those of human sperm on two loci: H19 and IGF2. These results demonstrate that male PSCs have the ability to differentiate directly into advanced germ cell lineages and may represent a novel strategy for studying spermatogenesis in vitro
View Publication
产品类型:
产品号#:
05850
05857
05870
05875
07923
85850
85857
85870
85875
产品名:
Dispase (1 U/mL)
mTeSR™1
mTeSR™1
Hu Y-L et al. (JUN 2007)
Blood 109 11 4732--8
Evidence that the Pim1 kinase gene is a direct target of HOXA9.
The HOXA9 homeoprotein exerts dramatic effects in hematopoiesis. Enforced expression of HOXA9 enhances proliferation of primitive blood cells,expands hematopoietic stem cells (HSCs),and leads to myeloid leukemia. Conversely,loss of HOXA9 inhibits proliferation and impairs HSC function. The pathways by which HOXA9 acts are largely unknown,and although HOXA9 is a transcription factor,few direct target genes have been identified. Our previous study suggested that HOXA9 positively regulates Pim1,an oncogenic kinase. The hematologic phenotypes of Hoxa9- and Pim1-deficient animals are strikingly similar. Here we show that HOXA9 protein binds to the Pim1 promoter and induces Pim1 mRNA and protein in hematopoietic cells. Pim1 protein is diminished in Hoxa9(-/-) cells,and Hoxa9 and Pim1 mRNA levels track together in early hematopoietic compartments. Induction of Pim1 protein by HOXA9 increases the phosphorylation and inactivation of the proapoptotic BAD protein,a target of Pim1. Hoxa9(-/-) cells show increased apoptosis and decreased proliferation,defects that are ameliorated by reintroduction of Pim1. Thus Pim1 appears to be a direct transcriptional target of HOXA9 and a mediator of its antiapoptotic and proproliferative effects in early cells. Since HOXA9 is frequently up-regulated in acute myeloid leukemia,Pim1 may be a therapeutic target in human disease.
View Publication
产品类型:
产品号#:
03434
03444
产品名:
MethoCult™GF M3434
MethoCult™GF M3434
Wernig M et al. (AUG 2008)
Nature biotechnology 26 8 916--24
A drug-inducible transgenic system for direct reprogramming of multiple somatic cell types.
The study of induced pluripotency is complicated by the need for infection with high-titer retroviral vectors,which results in genetically heterogeneous cell populations. We generated genetically homogeneous 'secondary' somatic cells that carry the reprogramming factors as defined doxycycline (dox)-inducible transgenes. These cells were produced by infecting fibroblasts with dox-inducible lentiviruses,reprogramming by dox addition,selecting induced pluripotent stem cells and producing chimeric mice. Cells derived from these chimeras reprogram upon dox exposure without the need for viral infection with efficiencies 25- to 50-fold greater than those observed using direct infection and drug selection for pluripotency marker reactivation. We demonstrate that (i) various induction levels of the reprogramming factors can induce pluripotency,(ii) the duration of transgene activity directly correlates with reprogramming efficiency,(iii) cells from many somatic tissues can be reprogrammed and (iv) different cell types require different induction levels. This system facilitates the characterization of reprogramming and provides a tool for genetic or chemical screens to enhance reprogramming.
View Publication