Pancreas microsomes

Fig. 3. Removal of PDI from dog pancreas microsomes. Dog pancreas microsomes after the various treatments were isolated by ultracentrifugation and separated on a 129c polyacrylamide gel in the presence of SDS. The gel was loaded as follows lane I, molecular-weight markers lane 2, untreated microsomes lane 3, pH 9-washed microsomes lane 4, saponin-washed (1%, w/v) microsomes lane 5, sonicated microsomes lane 6, pH 9-washed microsomes reconstituted with purified PDI.

Fig. 10. Cell-free synthesis of t-PA glycoforms. The niRNA coding for t-PA was translated in a rabbit reticulocyte lysate in the presence of dog pancreas microsomes. Microsonies were isolated posttranslationally and the translocated, glycosylated products were separated by SDS-PAGE. Translation was carried out under conditions that either prevented (lane 2) or allowed (lane 3) proper folding of the t-PA molecule, yielding enzymatically active protein that was sensitive to natural inhibitors and stimulators.

Herscovics, A., Bugge, B. Jeanloz, R.W. (1977) Effect of Bacitracin on the Biosynthesis of Dolichol Derivatives in Calf Pancreas Microsomes, FEBS Letters, 82, 215-8... 

Interpretation (1953-1955) of the ultrastructures which, after cell disruption and differential centrifugation, gave rise to microsomes, proved quite difficult. Porter described a vacuolar system with canal-iculi and cistemae which was particularly evident in protein-secreting cells such as the acinar cells of the pancreas. The appearance was... 

By using an HeLa cell-free system together with microsomes from dog pancreas, four proteins can be made from the 26 S RNA the capsid protein, the E1 protein, a protein with an of 62,000 (the p62 protein),... 

The hormones of adrenal glands, thyroid and pancreas exert various effects on the metabolism of drugs. Adrenalectomy of certain species e.g. rat impairs the metabolism of certain drugs, which can be reversed by administration of cortisone or prednisolone. Administration of ACTH, adrenaline or thyroxine impairs the hepatic microsomal metabolism of drugs. Thyroidectomy reduces the... 

Our study on the distribution of electron transferring proteins in animal sources is still in progress. From present knowledge, adrenodoxin can be found in adrenal cortexes from pig, beef, and rat. Further, a similar protein was isolated from pig testis (see II-A-2), and it was also found in the ovary. However, brain, heart, liver, kidney, and pancreas appear to lack adrenodoxin-like protein. If this is correct, the proteins of the ferredoxin family are located solely in the glands which directly act in the biosynthesis of steroid hormones. It is of interest that adrenodoxin-like protein does not participate in the steroid hydroxylation involved in cholesterol and cholic acid biosyntheses. All of these reactions without the participation of adrenodoxin are similar to enzymes responsible for microsomal non-specific hydroxylation, which consist of the following sequence of electron transfer ... 

Fig. 5. Cell-free translation of -y-gliadin mRNA. The -y-gliadin niRNA was translated in the absence (lanes 1 and 5) or presence (lanes 2-4 and 6) of dog pancreas inicrosomes. Translation products were separated by SDS-PAGE under reducing conditions (lanes I -3, 5, and 6) and under nonreducing conditions (lane 4). Lanes 1 and 5 are products of translation in the absence of microsomal vesicles lanes 3,4, and 6 are products of translation in the presence of microsomal vesicles translation products of lanes 3 and 4 were treated with proteinase K translation products of lane 6 were treated with 1 (v/v) Friton X-100 and proteinase K.

Sulfuric acid, phosphate, and sucrose extracts of mouse and beef pancreas have also been compared chromatographically on Amberlite IRC-50 (154). For both species, the sulfuric acid extracts give two peaks which correspond to ribonucleases A and B. When prepared from supernatant free of zymogen granules and microsomes, phosphate and sucrose preparations give a third peak, (10-15 % of the total activity in the case of mouse 1 % in the case of beef) which can be converted into the previous ones by acid treatment. This treatment induces a two- to three-fold increase in activity and the dissociation of the acidic compound already referred to above. The chemical structure of mouse ribonuclease(s) is still unknown. 

Leucine arylamidase (= leucine aminopeptidase) is a ubiquitous enzyme, mainly localized in the liver and bile ducts as well as in the pancreas, breast, intestine and kidney. During pregnancy (as from trimester), LAP increases. Arylamidases are predominantly localized in the cytoplasm, while aminopeptidases are found in the microsomes of hepatocytes. LAP splits aminoterminal amino acids off from peptides. High LAP activities are detectable in the epithelia of the bile ducts. 

The centrifugal method of separation employed by Van Lancker and Holtzer (V2) was among the earlier ones in the field, and there was probably considerable cross contamination of the fractions. Nonetheless, the distribution seems more disperse than that obtained by de Duve et al. (DIO) for rat liver with a comparable method. For example, in the case of the mouse pancreas the small mitochondrial fractions, c, d, and e, obtained by centrifugation between 17 X 10 and 263 X 10 gr-min contained 27% of the acid phosphatase and the succeeding microsomal fractions, f and g, obtained by centrifugations between 263 X 10 g-min and 3170 X 10 g-min, contained 24% of the acid phosphatase (V2). For rat liver, comparable fractions, obtained by centrifugation between 33 X 10 to 250 X 10 g-min and 250 X 10 to 3000 X 10 g-min contained 41 and 20%, respectively (DIO). 

GGT is present (in decreasing order of abundance) in proximal renal tubule, liver, pancreas, and intestine. The enzyme is present in cytoplasm (microsomes), but the larger fraction is located in the cell membrane and may transport amino acids and peptides into the cell across the cell membrane in the form of y-glutamyl peptides. It may also be involved in some aspects of glutathione metabolism. ... 

Changes in other organs, cells and organelles due to intoxication are now known, including histochemical changes in the pancreas [535], altered mixed function oxidase (MFO) in hepatic microsomes [536], changes in humoral and cellular immunity [537]— possibly due to chromosomal aberrations [538]—and in natural killer cells [539]. 

Russell and his associates [1183] first cloned mouse P450 2R1 in a search for a liver microsomal vitamin D3 25-hydroxylase. The mRNA is abundant in liver and testis of mice and was also identified (mice) in kidney, brain, epididymis, skin, heart, muscle, and spleen [1183]. In humans, a similar mRNA profile was reported [1186], with the highest levels in testis, followed by pancreas, and then the tissues reported by Cheng et al. [1183], including liver. Thus, P450 2R1 mRNA is expressed in many tissues. Protein detection has not been reported. 

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