ESC & iPSC News Volume 6.44 | Nov 9 2011

Ribosome Profiling of Mouse Embryonic Stem Cells Reveals the Complexity and Dynamics of Mammalian Proteomes
Here researchers present a suite of techniques, based on ribosome profiling, to provide genome-wide maps of protein synthesis as well as a pulse-chase strategy for determining rates of translation elongation. [Cell] Abstract

In Embryonic Stem Cells, ZFP57/KAP1 Recognize a Methylated Hexanucleotide to Affect Chromatin and DNA Methylation of Imprinting Control Regions
Here, investigators reveal that ZFP57, its cofactor KAP1, and associated effectors bind selectively to the H3K9me3-bearing, DNA-methylated allele of imprinting control regions in embryonic stem cells. [Mol Cell] Abstract

Surface-Engineered Substrates for Improved Human Pluripotent Stem Cell Culture Under Fully Defined Conditions
Here, researchers develop a spatially defined culture system based on UV/ozone radiation modification of typical cell culture plastics to define a favorable surface environment for human pluripotent stem cell culture. [Proc Natl Acad Sci USA] Abstract | Press Release

Highly Efficient Derivation of Ventricular Cardiomyocytes from Induced Pluripotent Stem Cells with a Distinct Epigenetic Signature
Here, scientists demonstrate that induced pluripotent stem cells (iPSCs) can be derived from murine ventricular myocytes (VMs), and consistent with other reports of iPSCs derived from various somatic cell types, VM-derived iPSCs exhibit a markedly higher propensity to spontaneously differentiate into beating cardiomyocytes as compared to genetically matched embryonic stem cells or iPSCs derived from tail-tip fibroblasts. [Cell Res] Abstract

The Metabolome of Induced Pluripotent Stem Cells Reveals Metabolic Changes Occurring in Somatic Cell Reprogramming
Researchers report, using an untargeted metabolomics approach, that human induced pluripotent stem cells (iPSCs) share a pluripotent metabolomic signature with embryonic stem cells that is distinct from their parental cells, and that is characterized by changes in metabolites involved in cellular respiration. [Cell Res] Abstract

Derivation of New Human Embryonic Stem Cell Lines Reveals Rapid Epigenetic Progression In Vitro That Can Be Prevented by Chemical Modification of Chromatin
Data demonstrate that self-renewal and survival of class I nuclei are compatible with normoxic human embryonic stem cell (hESC) derivation, and that chemical supplementation after derivation provides a strategy to prevent epigenetic progression and retain nuclei with two active X chromosomes in the self renewing state. [Hum Mol Genet] Abstract

Efficient Generation of Functional Hepatocytes from Human Embryonic Stem Cells and Induced Pluripotent Stem Cells by HNF4α Transduction
Although investigators recently reported that hepatic commitment is promoted by transduction of SOX17 and HEX into human embryonic stem cell- and induced pluripotent stem cell-derived cells, these hepatocyte-like cells were not sufficiently mature for drug screening. To promote hepatic maturation, they utilized transduction of the hepatocyte nuclear factor 4α (HNF4α) gene, which is known as a master regulator of liver-specific gene expression. [Mol Ther] Abstract

Resveratrol Protects Mouse Embryonic Stem Cells from Ionizing Radiation by Accelerating Recovery from DNA Strand Breakage
To learn whether resveratrol can protect stem cells from DNA damage and to study its effects on genomic integrity, scientists exposed mouse embryonic stem cells pre-treated with resveratrol to ionizing radiation. [Carcinogenesis] Abstract