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After cloning a gene of interest, many researchers wish to analyze its characteristics by overexpression analysis or by introduction of mutated forms of the gene of interest into various cell types. In the analysis of insulin-stimulated glucose transport, the most appropriate cell syst ...

The facilitative glucose transporters constitute a family of integral membrane proteins, each with different substrate specificities, tissue distribution, and transport kinetics. It is possible to localize and track movement of facilitative glucose transporters within a c ...

Working with single-mouse embryos at the blastocyst stage is difficult from a biochemical standpoint because of the paucity of tissue. Each blastocyst contains only 25 ng of total protein (1) and has a volume of approx 160 pL (2,3). In order to measure glucose uptake, many groups have pooled embryos to i ...

The ability of cells to transport glucose through the plasma membrane and into the cell for use in metabolism is of prime importance in cellular metabolism. This process occurs through a family of glucose transport proteins (1). In insulin-sensitive cells, such as heart, skeletal muscle, and ad ...

The gene-targeting technology allows complete and selective inactivation of a specific gene to study the consequence of total absence of the gene product. The availability of such null-mutant mice enables investigators to identify the biological function of the gene product in physi ...

This chapter on new methods of molecular biology applied to the investigation of the renin-angiotensin system (RAS) contains a description of a clinical case in its first section. There are two reasons for this. First, the case will illustrate the importance of increased understanding of the R ...

The advent of gene-targeting technology in embryonic stem cells has provided an important tool for the dissection of complex biological systems by allowing investigators to generate germ line mutations in selected genes. Since the introduction of this technology in the early 1980s, hu ...

Essential hypertension is a chronic cardiovascular disease that effects over 50 million people in the United States. It is a complex pathophysiological state that is primarily characterized by a sustained elevation in blood pressure (BP). If untreated, this chronically elevated BP can ...

In vitro translation is a powerful method for specifically investigating mRNA translation independently of transcription, post-translational processing, and protein trafficking. There are several well-characterized in vitro translation systems including mammal ...

Electromobility shift assays (EMSAs) provide a way to study proteinnucleic acid interactions. This method is based on the observation that the electrophoretic mobility of nucleic acids through polyacrylamide gels is retarded when bound to proteins. The mobility of nucleic acid-pr ...

cis-Acting DNA control elements, enhancers and promoters, function to control gene expression by acting as targets for specific DNA-binding proteins (trans-acting factors). trans-acting factors are sequence-specific DNA-binding proteins that recognize specific signat ...

Transcriptional control, the process controlling when and how much RNA is produced from a DNA template, is a major determinant of gene expression in eukaryotic cells. This process, intensely studied over the last few decades, is under control of specific DNA sequences (cis elements) that func ...

Becker-Andre and Hahlbrock first described competitive RT-PCR (1). In the competitive RT-PCR, a synthetic RNA/DNA control (competitor), generally called internal standard, is coamplified with the target nucleic acid in the same tube (2,3). Ideally, both target and internal standard wi ...

Antisense inhibition has been developed, particularly in cell-culture applications, to the point where it is being tested in clinical trials for HIV and cancer (1,2). The pros and cons of its use have been reviewed elsewhere (3). Before 1992, however, antisense (AS) had not been applied in vivo with any ...

Pregnancy begins with fertilization of the ovulated oocyte by the sperm. After fertilization, the egg undergoes time-dependent mitotic division while trying to reach the blastocyst stage and the uterus for implantation. Uterine preparation for implantation is regulated by coord ...

To date three distinct isoforms of nitric oxide synthase (NOS) have been identified. Two isoforms are considered to be expressed constitutively—neu-ronal NOS (nNOS; type I NOS) and endothelial NOS (eNOS; type III NOS). The third isoform is not generally present in normal cells and tissues but is i ...

The measurement of the concentration of nitric oxide (NO) is a challenging problem because of the short half-life of NO (t 1/2=3–6 s) in biological systems (1). The instrumental techniques used currently for NO measurements are spec-troscopic and electrochemical methods (2). Electrochem ...

Osteoporosis is a devastating disease that is characterized not only by a reduction in bone quantity but also by deterioration in bone quality. The quality of bone tissue is greatly influenced by its mechanical properties and, therefore, investigations into the etiology and enhanced det ...

The primary responsibility of the skeleton is to bear the loads involved in physical activity without sustaining damage. This capability involves a mecha-nism in which bone cells “assess” the suitability of the bones' existing architecture in relation to their prevailing loading envi ...

Thyroid hormone (T3) is an important signaling molecule for cardiac function. Chronic exposure of the heart to either elevated levels of thyroid hormone (hyperthyroidism) or lower thyroid hormone levels (hypothyroidism) have profound effects on cardiac output. Hyperthyroidi ...