Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.108 (TAT)
 2,389 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study aimed to evaluate the pattern of gene expression induced by activin A in mouse Embryonic Stem Cells (ESCs). Mouse ES cells cultured in undifferentiated state by leukemia inhibitory factor and feeder layer cells. Following removing these two anti differentiation factors for 5 days and forming Embryoid Bodies (EBs), the cells divided to 8 equal cells per groups. Differentiation procedure was performed in a two staged protocol; Formed EBs for 4 days (Stage one); expanded differentiated ESCs on gelatin coated dishes for one week (stage two). In the stage one, the media of groups 2-7 contained 10, 30 and 100 ng mL(-1) Activin A. The media in stage two was the same for all groups and contained only Fetal Bovine Serum (FBS). The expression of undifferentiated, ectoderm, mesoderm and endoderm markers were compared with relative RT-PCR method and statistically analyzed. The expression of an undifferentiating marker; Nanog was increased in the Activin A treated groups of stage one. The expression of OCT4 reduced in Activin A treated groups in stage two. In the stage one, the expression of Nodal increased by Activin A. expression of sonic hedgehog (Shh) was suppressed in Activin A treated groups of both stages. In stage two, there were significant decrease for the expression of mesoderm (Brachyury) and Nodal and visceral endoderm (GATA4) markers (p < 0.01). The expression of definitive endoderm markers (PDX1, TAT) showed significantly increased in Activin A treated groups (p < 0.01). Activin A induced differentiation in high concentration by imbalance in undifferentiating markers. Nodal has a dual role, undifferentiating effect and regulation of visceral endoderm towards definitive endoderm. Overexpression of Nanog, alteration in the expression of Nodal and Shh inhibition are three mechanisms for explanation of differentiation induced by activin A in ES cells. These mechanisms induces cascade of gene expression that commits ESCs towards definitive endodermal cells.
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PMID:Kinetics of gene expression during exposure of mouse stem cells to activin A. 1957 65

Direct differentiation of dopaminergic (DA) neurons from human pluripotent stem cells (hPSCs) in the absence of gene manipulation is the most desired alternative to clinical treatment of Parkinson disease. Protein transduction-based methods could be efficient, safe approaches to enhance direct differentiation of human embryonic stem cells (hESCs) to DA neurons. In the present study, we compared the differentiation efficiency of DA neurons from hESCs with and without the application of LIM homeobox transcription factor 1 alpha (LMX1A), a master regulatory protein in the development of the midbrain neurons and SHH proteins. The results obtained revealed that the treatment of hESCs with recombinant LMX1A (rLMX1A) protein along with dual SMAD inhibition led to higher expression of LMX1B, LMX1A, FOXA2, PITX3, EN1, and WNT1 effector endogenous genes and two-fold expression of PITX3. Moreover, the highest expression level of PITX3 and TH was observed when rLMX1A was added to the induction medium supplemented with SHH. To our best knowledge, this is the first report demonstrating the application of TAT-LMX1A recombinant protein to enhance hESC differentiation to DA as shown by the expression of DA specific makers. These findings pave the way for enhancing the differentiation of hESCs to DA neurons safely and efficiently without genetic modification.
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PMID:Efficient differentiation of human embryonic stem cells toward dopaminergic neurons using recombinant LMX1A factor. 3039 Feb 7