Effect of salinity on the osmotic,chloride, total protein and calcium concentrations in the hemolymph of the prawn Peneaus monodon (fabricius)

• 1.1. Osmolality and chloride concentrations in the hemolymph of Penaeus monodon became stable 1 day after molting in 32 ppt, while total protein and calcium concentrations remained stable throughout the molting cycle. When intermolt (≥ 36 hr postmolt) animals were transferred from control (32 ppt) to experimental (8–40 ppt) salinities, osmolality, chloride and total protein, but not calcium, concentrations in the hemolymph achieved steady state values 24–48 hr after transfer.
• 2.2. The hemolymph osmolality was a linear function (slope = 0.28) of medium osmolality at salinities between 8 and 40 ppt. It was isosmotic to seawater at 698 mOsm (10 g prawns) and 752 mOsm (30 g), and was hyperosmotic to the medium below isosmotic concentrations, and hypoosmotic to those above.
• 3.3. Hemolymph chloride concentration was isoionic to seawater at 334 mM, and was hyperregulated below isoionic concentrations, and hyporegulated to those above.
• 4.4. P. monodon maintained its hemolymph calcium concentration between 6.4 and 10 mM when medium salinities increased from 8 to 40 ppt.
• 5.5. Total protein concentration in the hemolymph was independent of medium salinity (8–40 ppt) and hemolymph osmolality (540–850 mOsm).

     

Characterization of the Melanoplus sanguinipes hemolymph after infection with Beauveria bassiana or wounding

• 1.1. The phenoloxidase activity, protein and carbohydrate levels were studied for 24 hr in the hemolymph of the migratory grasshopper, Melanoplus sanguinipes after artificial wounding of the insect cuticle or the injection of Beauveria bassiana conidia.
• 2.2. Injection or wounding induced a primary response and phenoloxidase activity was found to increase within 10–60 min. The values for phenoloxidase activity in viable B. bassiana-injected insects exhibited a secondary response, i.e., an increase 24 hr after injection.
• 3.3. In wounded insects and those injected with inactivated conidia, the phenoloxidase activity receded after the initial increase and remained at low levels.
• 4.4. Protein concentrations in the hemolymph increased immediately after infection and wounding and returned to basal levels during the course of the experiment.
• 5.5. Injection of viable B. bassiana resulted in a gradual increase in the protein concentrations between 12 and 24 hr.
• 6.6. There was no apparent change in the carbohydrate levels in either B. bassiana-infected or wounded insects.
• 7.7. These results are discussed in relation to their possible role(s) and interrelationships in the immune response to infection or wounding. Furthermore, we suggest that a “factor” is released after mechanical injury of the integument.

     

Seasonal changes of lipids and fatty acids in oyster tissues (Crassostrea virginica) and estuarine particulate matter

• 1.1. Lipid concentration in adductor muscle ranged from 2–68, in visceral mass from 5–28, in mantle and gill from 5–20 and in heart from 27.8–79 mg/g wet tissue. Particulate matter lipids varied from 1.0–2.6 mg/1 of estuarine water.
• 2.2. Neutral and polar lipids ranged from 25–38% of the total lipids in the oyster tissue and from 62–75% of the estuarine particulate organic matter.
• 3.3. Seasonal maxima of lipid concentrations varied among oyster tissues. Peak particulate lipids occurred in November.
• 4.4. It is proposed that seasonal variation in oyster lipids was more related to reproductive cycles than to food lipid supply.

     

Hemolymph ferritin and radula structure in the limpets Patelloida alticostata and Patella peronii (Mollusca: Gastropoda)

• 1.1. The mean concentration of total hemolymph iron was 3060μg/100 ml in Patella peronii and 2950μg/100 ml in Patelloida alticostata.
• 2.2. Ferritin was found to act as a major iron-binding protein in the hemolymph of both P. peronii and P. alticostata.
• 3.3. P. alticostata ferritin has a molecular weight of approximately 505,000, while that of P. peronii has a mol wt. of approximately 520,000.
• 4.4. The lateral radula teeth of both species are mineralized by deposits of silica (SiO₂) and iron in the form of goethite (α-FeOOH).
• 5.5. Hemolymph ferritin is suggested to act as a high capacity transport system to supply iron to the mineralizing front of the radula.

     

Identification and characterization of vitellin in a hermophrodite shrimp,Pandalus kessleri

• 1.1. A female specific protein (FSP, vitellogenin) in hemolymph and its related ovarian protein (vitellin) of Pandalus kessleri were studied by means of electrophoretical and immunological procedures.
• 2.2. The vitellin was purified from vitellogenic ovaries using hydroxylapatite, DEAE cellulose and Sepharose 6B columns, consecutively.
• 3.3. The vitellin had a molecular weight of approximately 560 kD and was composed of two subunits, 81 and 110 kD, respectively.
• 4.4. The vitellogenin concentrations in the hemolymph increased as vitellogenesis in the ovarian oocytes advanced and dropped markedly after the release of mature eggs.

     

Estimating the Contribution of Proteasomal Spliced Peptides to the HLA-I Ligandome*

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Highlights

• •Reported proteasomal spliced HLA peptides do not fit the consensus binding motifs.
• •Their MS/MS spectrum matches suggest that many of them are ambiguous.
• •Our workflow is based on de novo sequencing, alignment, and multiple search tools.
• •The upper bound proportion of cis-spliced peptides is 2–6% and likely much smaller.

     

Characterization of diverse hemolymph lectins in the cotton caterpillar Spodoptera littoralis

• 1.1. Hemolymph lectins (agglutinins) of the cotton caterpillar Spodoptera littoralis were analyzed by agglutination, cross-absorption and carbohydrate-hemagglutination inhibition using several vertebrate erythrocytes.
• 2.2. Lectins were found to interact, with all tested erythrocytes, by binding to carbohydrate moieties but showing no definite specificity.
• 3.3. Disulphide bonds were probably absent as 2-ME treatment was ineffective.
• 4.4. By cross-absorption studies, we have proposed that the hemolymph contains multiple lectins.

     

A comparison of aspartate transcarbamylase activity in juvenile pacific oysters (Crassostrea gigas) when fed various diets

• 1.1. The optimum pH for measurement of aspartate transcarbamylase activity in oyster tissue was determined to be 9.35 while the optimum temperature was 39.5°C.
• 2.2. Aspartate transcarbamylase activity varied significantly over short periods of time (hr) possibly due to fluctuations in the amount of food digested.
• 3.3. The composition of the oyster's diet also affected the levels of aspartate transcarbamylase activity in oyster tissues.
• 4.4. Those oysters fed an egg yolk-starch diet contained significantly lower aspartate transcarbamylase activity than oysters fed an egg yolk-starch-salmon oil diet or a casein-starch-salmon oil diet.
• 5.5. The aspartate transcarbamylase activities in oysters fed Phacedactylum tricornutum or a starch diet were not significantly different from the activities in oysters fed the egg yolk-starch diet.

     

Transport of cholesterol in the hemolymph of the mollusc Diplodon delodontus

• 1.1. The dietary and inter-organ cholesterol transport in the hemolymph of the bivalve mollusc Diplodon delodontus, was studied. Plasma and hemocytes were obtained after feeding labeled cholesterol to animals or injecting it into the posterior adductor muscle.
• 2.2. In both cases, cholesterol was incorporated either into plasma or hematic cells.
• 3.3. Two plasmatic fractions differing in their hydrated densities were recognized as cholesterol carriers and were isolated. They have characteristics of high density (HDL) and very high density (VHDL) lipoproteins, respectively.
• 4.4. The major lipids in the different classes of lipoproteins were free sterols in HDL and phospholipids in VHDL.
• 5.5. Neither low nor very low density lipoprotein transporting cholesterol was detected.

     

Cotranslational fatty acylation of mucus glycoprotein. Addition of palmitic acid to peptidyl-tRNA occurs prior to peptide chain completion and its release

• 1.1. The fatty acylation of mucus glycoprotein nascent peptides was investigated using [³H]palmitic acid and [³⁵S]methionine-labeled peptidyl-tRNA of rat gastric mucous cells.
• 2.2. The mucus glycoprotein peptidyl-tRNA fraction was found to contain covalently bound palmitic acid in its complexes.
• 3.3. RNase digestion of the mucus glycoprotein peptidyl-tRNA released [³H]palmitic acid labeled peptides which, on SDS-polyacrylamide gel, separated into a multitude of bands ranging in size from 2000 to 60,000 Da.
• 4.4. The analyses of low molecular weight peptides revealed that palmitic acid was present in methionine-labeled peptides containing 30–43 amino acids and those of 18–25 amino acids or larger devoid of methionine, but was not identified in methionine-labeled peptides containing 10–15 amino acids.
• 5.5. The results indicate that the N-terminal fatty acylation of mucus glycoprotein nascent peptides is a cotranslational process which is occuring in an immediate vicinity of the signal peptide fragment.

     

Induction of locomotor behavior in the giant African snail,Achatina fulica

• 1.1. The locomotor-inducting factor of the giant African snail, Achatina fulica, was examined.
• 2.2. Snails showed nocturnal circadian behavior in relative humidity at least over 50%. Although the rhythmicity was independent of light and darkness, it was disturbed easily by hydration, and hydrated snails continued to locomote throughout the day. For induction of locomotor behavior, relative humidity over 50% was the fundamental factor and water is shown to be the limiting factor for the endogeneous circadian oscillator.
• 3.3. The integument of snails showed a higher water permeability. Through the integument, hemolymph osmolality changed easily according to hydration and dehydration from about 120 to 400 mOsm/kg H₂O. Circadian behavior was induced in snails in which hemolymph osmolality ranged from about 130 to 230 mOsm/kg H₂O.
• 4.4. By hydration, hemolymph osmolality in quiescent and estivated snails which have higher osmolality decreased gradually and then they began to locomote according to the degree of dilution, and vice versa. The induction of behavior in these snails was controlled by low hemolymph osmolality.
• 5.5. Together with the endogeneous rhythmicity, water environment was shown to be the key factor for the induction of locomotor behavior.
• 6.6. Based on these results, the mechanisms of the induction of locomotor behavior in terrestrial pulmonates are proposed.

     

Purification and characterization of vitellogenin from the American cockroach,Periplaneta americana

• 1.1. Vitellogenin (VG) was isolated and purified from the hemolymph of female American cockroaches.
• 2.2. The purification method used in this study comprises two steps: the first step is based on the method originally developed for purifying lipophorin from hemolymph, and the second step is the separation of VG from lipophorin by a KBr density gradient ultracentrifugation.
• 3.3. The purified VG was characterized according to molecular weight, substructure, shape and size, and lipid composition.
• 4.4. The VG molecule is almost globular in shape with the diameter of about 15.5 nm and is indistinguishable from lipophorin in shape and size.
• 5.5. The native molecular weight determined by light scattering method was 560 kDa.
• 6.6. The VG consists of four subunits with molecular weights of approximately 102, 81, 49 and 40 kDa, respectively.
• 7.7. VG is a lipoprotein and comprises 92% protein and 8% lipid.
• 8.8. Major lipid components were found to be diacylglycerol (25%) and phospholipids (71%).

     

The qualitative and quantitative analysis of insect hemolymph sugars by high performance thin-layer chromatography

• 1.1. A procedure is described for the analysis of sugars in insect hemolymph by high performance thin-layer chromatography.
• 2.2. Densitometric scanning of spots after plate developments shows linear responses with most sugars in an analytical range of 125ng-2.0 /gmg; detection limits range from 30/2–60 ng.
• 3.3. Quantitative measurements of trehalose, glucose and fructose can be made on hemolymph sample volumes of less than one microliter, allowing blood sugar analysis of individual insects.
• 4.4. Hemolymph sugar determinations on six species of insects agree well with values reported in the literature, but mean values for a species often showed higher variability because samples were taken from individuals.

     

Hyperosmotic properties of the fluids of the perivisceral coelom and water vascular system of starfish kept under stable conditions

• 1.1. Osmotic measurements were made on the perivisceral coelomic and water vascular fluids of 4 species of northwest Pacific starfish and their stable sea-water media.
• 2.2. Mean levels of both fluids were hyperosmotic in every species, often at statistically significant levels.
• 3.3. For all species combined, mean hyperosmolality (mosmol/kg ± SE) of perivisceral coelomic fluid was 1.49 ± 0.17, and water vascular fluid 6.07 ± 0.74.
• 4.4. The hyperosmotic nature of these fluids contributes to water balance, working in conjunction with madreporitic inflow and other factors.

     

Sex-specific gene expression in distinct tissues of the shrimp Penaeus vannamei

• 1.1. Soluble proteins extracted from male and female Penaeus vannamei tissues such as eyes, eyestalks, brain, nerve cord, hemolymph, heart, muscle, hepatopancreas, hepatopancreas membrane and cuticular epidermis were analyzed and compared by high-resolution mini-two-dimensional polyacrylamide gel electrophoresis (mini-2D-PAGE).
• 2.2. In each shrimp tissue a large number of discrete polypeptides was observed.
• 3.3. The polypeptide patterns from the same tissue of female and male shrimp were mostly similar but both qualitative and quantitative differences were noted, suggesting the presence of sex-specific gene products in various shrimp tissues.
• 4.4. Future applications of these results are discussed.

     

A halogenated amino acid-containing sperm activating peptide and its related peptides isolated from the egg jelly of sea urchins,Tripneustes gratilla,Pseudoboletia maculata,Strongylocentrotus nudus,Echinometra mathaei and Heterocentrotus mammillatus

• 1.1. Twenty-eight peptides were isolated from the egg jelly of sea urchins, Tripneustes gratilla, Pseudoboletia maculata, Strongylocentrotus nudus, Echinometra mathaei (type A and B) and Heterocentrotus mammillatus and their amino acid sequences were determined.
• 2.2. Two of the peptides obtained from T. gratilla egg jelly possessed a bromophenylalanine (Br-Phe) residue in their sequences (Gly-(Br-Phe)-Asn-Leu-Asn-Gly-Gly-Gly-Val-Gly and Gly-(Br-Phe)-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly).
• 3.3. All of the peptides elevated cyclic GMP concentrations in the spermatozoa of the respective sea urchin and caused a shift in the apparent mol. wt of a major sperm protein of the respective sea urchin.
• 4.4. They stimulated respiration rates of the spermatozoa of Hemicentrotus pulcherrimus as well as their own species.
• 5.5. One-half maximal concentrations of the peptides for respiratory stimulation of H. pulcherrimus spermatozoa were between 10⁻¹¹ M and 10⁻⁹ M except a methionine-containing peptide which was about 10⁻⁷ M.

     

Phenoloxidase activity of acridid grasshoppers from the subfamilies melanoplinae and oedipodinae

• 1.1. Phenoloxidase activity and wound melanization was studied in five species of grasshoppers representing the subfamilies Melanoplinae and Oedipodinae.
• 2.2. Most of the phenoloxidase activity was detected in the plasma fraction of grasshopper whole-body homogenates and supernatant fractions of the hemolymph. The species representing the Oedipodinae had 20–50% higher percentage of the total phenoloxidase activity associated with particulate matter from a whole-body homogenate when compared to the Melanoplinae.
• 3.3. Phenoloxidase activity could not be detected in sclerotized cuticle of adult grasshoppers.
• 4.4. The phenoloxidase existed as a zymogen which could be activated by chymotrypsin and inhibited by KCN and NaCN while EDTA showed no effect. It had optimum activity at 37°C and pH 7.3.
• 5.5. These findings are discussed in relation to wound repair and immune responses to infection in grasshopper species.

     

Metabolic roles of carnitine expressed through the carnitine acetyltransferase system in Candida pintolopesii

• 1.1. The carnitine-responsive mutant yeast, Candida pintolopesii ATCC 26014 and the wild type strain (ATCC 22987) were used to investigate the role of carnitine and the carnitine acetyltransferase system.
• 2.2. [³H]l-Carnitine, supplied to the cells, was incorporated into acetylcamitine and [¹⁴C]pantothenate was incorporated into CoA and its derivatives.
• 3.3. Both bioautography and quantitative assays indicated that the relative amounts of CoA and acetylCoA were very different in the mutant and wild type cells.
• 4.4. The wild type yeast maintained an acetylCoA/CoA ratio of 0.33 ± 0.09 indicating that most of the CoA in the cell is in the free CoA form. Carnitine was not required to establish this ratio nor did its presence lower it further.
• 5.5. In contrast, the mutant cells contained a high acetylCoA/CoA ratio (12.8 ± 3.0).
• 6.6. In the mutant cells, carnitine lowered the ratio by decreasing the intracellular acetylCoA concentration and releasing free CoA.
• 7.7. These data indicated that wild type yeast possess an effective mechanism that is not related to the CAT system for regulating the acetylCoA/CoA ratio.
• 8.8. This mechanism appears to be lacking in the mutant. The CAT system decreased the acetylCoA/CoA ratio in the mutant cells but not to the value which is found in the wild type strain.
• 9.9. In both stains of Candida pintolopesii, in the presence of carnitine, an acetylcamitine pool can be created whose concentration exceeds that of acetylCoA.
• 10.10. The intracellular apparent equilibrium constant (K_app) for carnitine acetyltransferase for wild type Candida pintolopesii ATCC 22987 was 0.73 ± 0.12, close to the established value of 0.6, indicating that the CAT system ran close to equilibrium.
• 11.11. The K_app for the CAT system of the carnitine-responsive mutant yeast was 7.7 ± 1.7 indicating that this reaction was not at equilibrium.

     

Increased muscle glucose uptake in response to chronic glyburide treatment is not related to changes in glucose transporter (GLUT4) protein

• 1.1. The mechanism of action of glyburide (a sulfonylurea) on muscle has been investigated by measuring glucose uptake and glucose transporter (GLUT4) protein levels after chronic glyburide treatment.
• 2.2. A dietary induced insulin resistant rat model (4 wk of high-fat, high-sucrose feeding) was given glyburide (2mg/kg/day) for 10 days and glucose uptake was measured in a perfused hindquarter preparation.
• 3.3. Protein levels of the GLUT4 glucose transporter were determined by Western analysis.
• 4.4. After 7 days of treatment, rats fed glyburide had lower blood glucose concentrations 2 hr (72 ± 5 vs 103 ± 12 mg/dl) and 24 hr (97 ± 7 vs 123 ± 7 mg/dl) after glyburide administration with no difference in serum insulin levels compared to vehicle treated animals.
• 5.5. Glucose uptake was approx doubled in basal state (0 insulin) in response to glyburide (2.8 + 0.4 vs 1.7 ± 0.2μ mol/g per hr).
• 6.6. Maximal insulin (100 nM) stimulated glucose uptake tended to be higher in the glyburide treated group, but did not reach statistical significance (8.0 ± 0.7 vs 7.0 ± 0.6 μmol/g per hr).
• 7.7. Western analysis revealed no significant effect of glyburide on the GLUT4 protein level in skeletal muscle.
• 8.8. These results suggest that glyburide alters glucose uptake through some mechanism other than alterations in the level of the GLUT4 glucose transporter protein.