Isozyme expression

Roberts, R. E., and McLean, W. G. (1997). Protein kinase C isozyme expression in sciatic nerves and spinal cords of experimentally diabetic rats. Brain Res. 754, 147-156. 

Yu, H.J., Unnerstall, J.R., and Green, R.D. 1995. Determination and cellular localization of adeny-lyl cyclase isozymes expressed in embryonic chick heart. FEBS Lett. 374 89-94. 

The most critical component for the study of metastasis is metastasizing cells. Since most people obtain their cells from cell culture, it is important to outline some of the criteria for the proper preparation and maintenance of those cultures. Details are omitted regarding verification of species of origin (karyotype, isozyme expression, etc.), tissue of origin (surface markers, enzyme expression patterns) and absence of opportunistic infections. It is presumed that such characterization will be done by readers of this volume before any... 

Table I summarizes the result of several studies that surveyed PKC isozyme expression in extracts or homogenates of intact smooth muscle or cultured smooth muscle cells by immunoblotting with type-specific antibodies. A consistent finding is that multiple PKC isozymes are expressed in various smooth muscles, and in most cases one PKC isozyme from each group (usually a, 8, and Q is expressed. PKC, which is abundant in swine carotid, appears to be expressed in only a few other vascular tissues. Likewise, PKCe from the nPKC group appears to be variably expressed. Considering the diversity in smooth muscle embryological origins (Miano et al., 1994), it might be expected that some of the PKC isozymes, which were noted earlier to be variably expressed in...

These data raise questions regarding the stability of the PKCp message in VSM and/or the specificity of p-subtype-specific antibodies, but illustrate the importance of verifying isozyme expression at both the mRNA and protein levels. A similar pattern of PKC isozyme expression (a, 8, e,, ) in cultured rat aortic VSM has been reported by Ali et al. (1994). Additional... 

Growth hormone-dependent and -independent regulation of cytochrome P-450 isozyme expression in streptozotocin-diabetic rats. Endocrinology 128, 2065-2076. 

Thigpen AE, Silver Rl, Guileyardo JM, et al. Tissue distribution and ontogeny of steroid 5a-reductase isozyme expression. J Clin Invest 1993 92 903-910. 

Legume root nodules are known to have high LOX activity with specific LOX isozymes expressed in nodules. A LOX cDNA from a root nodule library was reported to be very highly expressed in nodules, highly in epicotyls and moderately in roots, but was not detected in leaves, stem or flowers [51,52]. It was highly expressed in the root nodule parenchyma similar to defence proteins. It was not expressed in the senescence zone. A novel extracytoplasmic LOX was found in the lumen oi Rhizobium-miactA infection threads. 

During digestion and transfer across the small intestine, and in the liver, flavanols are rapidly metabolized in phase I and phase II biotransformations to various 0-sulfated, <9-glucuronidated and (7-methylated forms. Various UGT isozymes, expressed in the intestine and in the Uver, have been identified to catalyze the glucuronidation of flavonoids. In humans consuming cocoa, plasma levels of non-methylated epicatechins such as epicatechin-7-sulfate and methylated metabolites such as 3 -0-methylepicatechin have been reported to occur in micromolar concentrations within 1 h after intake. Metabolic studies have confirmed the presence of these conjugates in the plasma and urine of rodents and humans, as well as in the bile and brain of rats. It has been reported that colonic microflora can break flavonoids flavan structure to form simple phenolics and rig-flssion metabolites that may be physiologically relevant. 

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