细胞技术

The efficient generation of mesenchymal cells such as adipocytes, osteoblasts, and chondrocytes from embryonic stem cells is achieved by following sequential steps: embryoid body formation, retinoic acid (RA) treatment, and exposure to specific reagents for differentiation. ...

The process of bone formation can be approximated in vitro in the form of a mineralized nodule. Osteoprogenitors and mesenchymal stem cells, the immediate precursors to the osteoprogenitor, when placed into culture proliferate and differentiate into osteoblasts. These osteoblas ...

Pluripotent embryonic stem (ES) cells have complete potential for all the primary germ layers, such as ectoderm, mesoderm, and endoderm. However, the cellular and molecular mechanisms that control their lineage-restricted differentiation are not understood. Although embryoid ...

The model system of embryonic stem (ES) cell differentiation in vitro via cellular aggregates (embryoid bodies, EBs) can be used to analyze cell differentiation from a pluripotent stem cell via progenitor cells up to terminally differentiated cell types. ES cells are known to be pluripoten ...

In vitro culturing of mammalian cells provides an elegant platform to study cell signaling, interactions, and metabolism as well as proliferation and differentiation processes. Often, these cells are cultured and maintained in sera obtained from animals such as horses, cows, and rabbi ...

By directed differentiation using the hanging drop method, cardiomyocytes (CMs) can be derived from mouse embryonic stem cells. These spontaneously active CMs can then be isolated from the embryoid bodies and studied electrophysiologically for analysis of arrhythmic potential. ...

We present a protocol that has been developed for induction of the differentiation of murine embryonic stem (ES) cells to alveolar type II cells. With this protocol, undifferentiated murine ES cells are induced to form embryoid bodies (EBs). The 10-d-old EBs are trans-ferred to adherent culture ...

Mature hematopoietic cells, like all other terminally differentiated lineages, arise during ontogeny via a series of increasingly restricted intermediates. Hematopoietic progenitors have their origin in the mesoderm, which gives rise to hemangioblasts that can different ...

The orphan homeobox gene Hex has been shown to be critical for normal murine liver development using Hex -/- mice. Because of the early lethality of the Hex -/- mice, however, in vitro embryonic stem cell differentiation assays were employed to elucidate the role of Hex in murine hematopoiesis. These st ...

The thyroid gland is centrally important in metabolic homeostasis, growth, and development. Defects in any of the multiple steps required for normal thyroid development and thyroid hormone synthesis have been shown to result in thyroid-dependent pathology in a variety of animal models ...

Application of phylogenetic inference methods to comparative endocrinology studies has provided researchers with a new set of tools to aid in understanding the evolution and distribution of gene families. Phylogeny, as defined by Hillis et al. (1), is the “historical relationships am ...

The glucocorticoid receptor (GR) resides in the cytoplasm as a complex with chaperones. Upon ligand association, GR shuttles into the nucleus, and binds to its hormone response elements to control expression of particular genes (1-7). Transcriptional regulation by GR is thought to be a cons ...

Human progesterone receptor (PR) is a member of the nuclear hormone receptor superfamily of transcriptional activators, which share a common modular structure consisting of a C-terminal ligand-binding domain (LBD), a highly conserved and centrally located DNA-binding domain (D ...

Protein purification and characterization is required for a full understanding of structure-function relationships. Because proteins have complex structures and can be present at low concentrations, efficient purification protocols are needed. Purification of full-l ...

The nuclear receptor superfamily is composed of over 150 inducible transcription factors, most of which (1-2) do not have well characterized ligands to date. Nuclear receptors regulate promoters through specific protein-protein and protein-DNA interaction at their hormone resp ...

Nuclear receptors are organized into distinct functional domains, of which the most conserved is a 66-amino-acid DNA-binding domain (DBD) (1). This region, in some cases together with its C-terminal extension into the hinge region, imparts the receptor's ability to bind to target DNA sequen ...

Steroid hormones, estrogen, and progesterone, promote extensive cell proliferation, differentiation, and remodeling in all compartments of the uterus during pregnancy (1-5). These hormones orchestrate the entry of the fertilized ova into the uterus, prepare the uterus for embryo ...

Nature has made extensive use of metals in biological systems. Metals perform a wide variety of essential biological functions, such as oxygen and electron transfer, the development of structural framework, and they represent the reactive centers in catalytic proteins. The investig ...

Orphan nuclear receptors have been identified using a variety of methods over the years. The first were identified by low-stringency hybridization using known receptors as probes. This strategy has been successful because members of the steroid receptor superfamily contain a conse ...

There are two key elements that regulate steroid hormone action, as summarized in Fig. 1. First, steroid hormones regulate gene transcription by binding to specific intracellular receptors. The receptors are structurally homologous members of the steroid/thyroid hormone recept ...