Embryonic stem cells (ESCs) are pluripotent cells that can be cultured indefinitely, and maintain their capability to differentiate into all cell lineages. To maintain these cells as well as various types of related induced stem cells and progenitor cells in culture, Mouse Embryonic Fibroblasts (MEFs) are routinely used as feeder cells, largely to serve as a source of Leukemia Inhibitory Factor (LIF). ESCs can also be cultured without feeders if the medium is supplemented with recombinant LIF and other factors.

The retinoid-related orphan receptors alpha, beta and gamma (RORalpha, beta and gamma , also referred to as NR1F1, 2 and 3, respectively) comprise a distinct subfamily of nuclear receptors. Study of ROR-deficient mice has implicated RORs in the regulation of a number of biological processes and revealed potential roles for these proteins in several pathologies. NIH investigators have developed an in-vitro system using CHO cells stably expressing a TET-On expression vector regulating RORgamma and a RORE-Luciferase reporter.

The glucocorticoid receptor (GR) functions as a hormone-dependent transcription factor that is involved in the maintenance of basal and stress-related homeostasis. Serine 134 is a newly discovered phosphorylation target on the human glucocorticoid receptor that becomes phosphorylated during stress-activating conditions such as ultraviolet irradiation, nutrient starvation, and oxidative stress. The inventors have developed a rabbit polyclonal antibody that specifically recognizes the Ser 134 phosphorylated form of the human glucocorticoid receptor.

NIH Inventors have recently discovered a novel Leucine-rich repeat and calponin homology domain-containing protein 4 (Lrch4) in a proteomic screen of the plasma membrane of lipopolysaccharide (LPS)-exposed macrophages. Expression data by RT-PCR revealed that all Lrch family members (1-4) are expressed in macrophages, but only Lrch4 was recruited into lipid rafts (signaling microdomains of the plasma membrane) by LPS. Lrch4 is the most highly expressed Lrch family member in mouse tissues. It is a predicted single-spanning transmembrane protein that is encoded by the Lrch4 gene in humans.

The National Institutes of Health announces polyclonal antibodies against mouse cytochrome P450s CYP2J and CYP2C. Cytochrome P450s catalyze the metabolism of a wide range of exogenous compounds, including drugs, industrial chemicals, environmental pollutants, and carcinogens. The 2C family of cytochrome P450 metabolizes an extensive number of drugs which include tolbutamide, S-Warfarin, mephenytoin, diazepam and taxol. Many of the P450 enzymes are also active in the NADPH-dependent oxidation of arachidonic acid to various eicosanoids found in several species.

Available for licensing are monoclonal antibodies targeting human DNA polymerase beta (Pol B). Pol B is a constitutively expressed "housekeeping" enzyme that plays a role in base excision repair (BER), a cellular defense mechanism that repairs DNA base damage and loss. Aberrant Pol B expression is associated with genomic instability indicating that Pol B is required for DNA maintenance, replication and recombination.

HSPA2 is a member of the HSP70 family of heat-shock proteins that serve as molecular chaperones. Researchers discovered that HSPA2 protein is expressed in spermatogenesis during the meiotic phase. Spermatogenic cells lacking the HSPA2 protein arrest in mid-meiosis and undergo apoptosis. HSPA2 is present in the synaptonemal complex of wild-type mice and the chromosomes fail to separate in HSPA2-deficient mice (previously known as Hsp70-2-/- mice), suggesting that HSPA2 is required for the chromosomal events of meiosis such as synapsis, crossing over, or recombination.

HSPA2 is a member of the HSP70 family of heat-shock proteins that serve as molecular chaperones. Hspa2-cre expression mimics the spermatogenic cell-specific expression of endogenous HSPA2 within the testis, being first observed in leptotene/zygotene spermatocytes. Expression of the transgene is also detected at restricted sites in the brain, as occurs for endogenous HSPA2.

One of the primary means for treating HIV infection is the use of antiviral nucleotide or nucleoside analogs. These analogs work by inhibiting the activity of reverse transcriptase, the enzyme responsible for preparing the HIV genome for integration into the DNA of the host cell. Although these analogs do not have an effect on the polymerases responsible for replicating the human genome, the polymerase responsible for replicating the mitochondrial genome is sensitive to these analogs.

GLI-similar (Glis) 1-3 proteins constitute a subfamily of the Krüppel-like zinc finger transcription factors that are closely related to the Gli family. Mutations in human GLIS3 have been implicated in a syndrome characterized by neonatal diabetes and congenital hypothyroidism (NDH) and in some patients accompanied by polycystic kidney disease, glaucoma, and liver fibrosis. To further identify and study the physiological functions of GLIS3, NIEHS investigators generated mice in which GLIS3 is ubiquitously knocked out (GLIS3-KO) or conditionally knocked out in a cell type-specific manner.