Vitellogenesis in the shrimp,Penaeus vannamei: in vitro studies of the isolated hepatopancreas and ovary

• 1.1. Yolk proteins were isolated from ovaries of the shrimp Penaeus vannamei and used as an antigen for antibody production in rabbits.
• 2.2. Protein synthesis was measured for both the hepatopancreas and the ovary in vitro, and proteins present in both tissues were immunoreactive with the antibodies.
• 3.3. Extracts of shrimp eyestalks inhibited in vitro protein synthesis by both tissues. The inhibitory factor from the eyestalks was heat stable and had a molecular weight of 3300 daltons.

     

Palmitic acid metabolism in hepatopancreas of the freshwater shrimp Macrobrachium borellii

• 1.1. The palmitic acid fate as substrate for the synthesis of either glycerides or other fatty acids was studied in vivo and in the microsomal fraction from hepatopancreas of Macrobrachium borellii.
• 2.2. Most of the palmitic acid administered in vivo circulated to the hepatopancreas, being incorporated mainly in the triacylglycerol (TG) fraction.
• 3.3. Palmitic acid transformations into palmitoleic, stearic and oleic acids were observed in the hepatopancreas.
• 4.4. The in vitro biosynthesis of TG in hepatopancreas was more active than in other tissues. In the microsomal fraction, palmitic acid was also incorporated mainly in TG, and followed the α-glycerophosphate pathway.

     

Size-dependent haemagglutinating activity in the haemolymph from sub-adult blue shrimp (Penaeus stylirostris stimpson)

• 1.1. The blue shrimp (Penaeus stylirostris) haemolymph is capable of agglutinating the red blood cells of several vertebrates to different titres. However, the haemagglutinin is considered non-specific because it is incapable of differentiating erythrocytes of human blood types A, B and O.
• 2.2. Haemagglutinating activity and serum protein content were determined for male and female blue shrimp ranging in size from 8.5 to 16 cm. Haemagglutinating activity decreased significantly with animal size, while protein content was unaffected.
• 3.3. The above finding is probably related to maturation of the immune system and could explain the higher susceptibility of young shrimp to parasitic and viral diseases.

     

Carbohydrate metabolism during osmoregulation in Chasmagnathus granulata dana, 1851 (crustacea,decapoda)

• 1.1. Since glucose is one of the main energetic substrates for general metabolic processes in crustaceans, analysis of carbohydrate levels can furnish information on the energy metabolism of intact animals during osmoregulation.
• 2.2. Different groups of Chasmagnathus granulata were transferred to different salinities (0 and 40%), and the glucose and glycogen concentrations in blood, gills, muscle and hepatopancreas were determined at the beginning of the experiment and 24, 72, 168 and 360 hr after the salinity changes.
• 3.3. Differences in tissues carbohydrate levels were observed between summer and winter, that reflected differences in reserve mobilization.
• 4.4. In the summer, hypo- and hyperosmotic shocks induced an increase in carbohydrate levels in almost all tissues studied, indicating gluconeogenesis.
• 5.5. In the winter, a carbohydrate mobilization occurred only in the gills and hepatopancreas after both osmotic shocks.
• 6.6. Thus, the substrate reserve used for energy production required for osmoregulation seems to be dependent on the season and tissues.

     

S-Adenosyl-l-methionine decarboxylase activities in Mytilus edulis

• 1.1. The activities of S-adenosylmethionine decarboxylase (EC 4.1.1.50) were measured in cell extracts of mantle, hepatopancreas and foot from Mytilus edulis.
• 2.2. The apparent molecular weights of the enzymes estimated by gel filtration chromatography were 65,000 ± 10,000.
• 3.3. The enzymes do not require bivalent cations for catalysis and show optimum pH between 7.0–8.0 in phosphate buffer.
• 4.4. The hepatopancreas enzyme shows different behavior to the other two enzymes against temperature and its activity is strongly inhibited by NH₄⁺.
• 5.5. The apparent K_ms for S-adenosylmethionine were found to be 300, 200 and 250 μM for the hepatopancreas, mantle and foot enzymes, respectively.

     

Seasonal variation in the energy metabolism in an estuarine crab,Chasmagnathus granulata (Dana, 1851)

• 1.1. The effects of seasonal variation on the carbohydrate and lipid metabolism of the Chasmagnathus granulata were investigated.
• 2.2. Glycemia is high in winter and summer and low in spring and fall.
• 3.3. The glycogen content in the hepatopancreas and muscle is higher in fall and winter, and decreases during spring and summer.
• 4.4. The muscle lipids are higher in summer, and decrease during fall and winter whereas hepatopancreas lipids are higher except in the fall.
• 5.5. The crabs show change in the metabolic pattern of lipids and carbohydrates during the seasons of the year.

     

Effects of starvation and a carbohydrate-rich diet on glycogen metabolism in a gastropod mollusc,Megalobulimus oblongus

• 1.1. Administration of a carbohydrate-rich diet increased haemolymph glucose levels and glycogen concentration in hepatopancreas, mantle and muscle.
• 2.2. Glycogen concentration in tissues decreases after 2 weeks of starvation and haemolymph glucose levels did not change significantly.
• 3.3. However, starvation did not induce a decrease in the intrinsic synthetic capacity in tissues.
• 4.4. Glycogen synthesis in tissues from animals fed with lettuce or a carbohydrate-rich diet, increases with increasing glucose concentration in the media.
• 5.5. However, in mantle slices from snails adapted on a carbohydrate-rich diet, the glycogen synthetic capacity was lower than in slices from snails fed with lettuce.

     

An anticoagulant solution for haemolymph collection and prophenoloxidase studies of penaeid shrimp (Penaeus californiensis)

• 1.1. An anticoagulant solution was designed from data on osmolality, ionic concentration and pH to resemble shrimp haemolymph.
• 2.2. This Shrimp Salt Solution (SSS) prevents coagulation and prophenoloxidase system activation during the extraction of shrimp haemolymph.
• 3.3. The location of the the proPO system in the brown shrimp (Penaeus californiensis) was determined using this anticoagulant solution.

     

Radioimmunological quantification of C21, C19 and C18 steroids in the gonads of Locusta migratoria migratorioides R. and F.

• 1.1. Levels of progesterone, pregnenolone, testosterone, 5α-dihydrotestosterone, estrone and estradiol were measured by radioimmunoassay in purified gonadal extracts of larval and adult male and female Locusta migratoria.
• 2.2. The average steroid contents varied between less than 1 ng to more than 160 ng/g tissue.
• 3.3. Young adults were treated with precocene or ketoconazole in an attempt to influence the steroid contents in gonads.
• 4.4. Ketoconazole treatment had no effect on the steroid contents in gonads whereas precocene treatment resulted in higher contents of androgens.

     

Ontogenic change of digestive enzymes in Penaeus monodon

• 1.1. Ontogenic changes of both proteases and carbohydrases of Penaeus monodon from different larva stages to adult were investigated.
• 2.2. Total protease activity was low during nauplius and zoea but peaked up in mysis. This was due to the activity increase of both trypsin and chymotrypsin.
• 3.3. The change of isozyme pattern of these two enzymes from different life stages of the shrimp was further determined by functional staining on an electrophoregram.
• 4.4. Activity of α-amylase increased after the post-larva stage, while that of chitinase and maltase showed a peak in zoea then gradually decreased to adult.
• 5.5. The ratio of α-amylase activity to protease coincided with the dietary change of the shrimp in different life stage.

     

Gender-related differences of mouse liver d-aspartate oxidase in the activity and response to administration of d-aspartate and peroxisome proliferators

• 1.1. The hepatic d-aspartate oxidase activity was found to be higher in female ddY and ICR mice than in their male counterparts. On the contrary, the free d-aspartate content in the liver was lower in female mice than in male mice, suggesting that d-aspartate is actually metabolized by d-aspartate oxidase in vivo.
• 2.2. Oral administration of d-aspartate to the animals increased the hepatic d-aspartate oxidase activity 2–3 fold in both genders without any significant difference in the rate of the increase between the genders.
• 3.3. Several peroxisomal enzyme activities other than d-aspartate oxidase examined were not affected by this treatment.
• 4.4. Experiments in vitro suggested that the increase in the d-aspartate activity might be explained in part by stabilization of the enzyme by d-aspartate.
• 5.5. The administration of clofibrate, a peroxisome proliferator, to male mice, increased the hepatic d-aspartate oxidase activity with a significant simultaneous decrease of d-aspartate content in the liver, in agreement with a possible role of the enzyme n vivo.
• 6.6. On the other hand, the administration of clofibrate or dehydroepiandrosterone to female mice decreased the d-aspartate oxidase activity.
• 7.7. The peroxisome proliferators were suggested to act to eliminate the gender difference of hepatic d-aspartate oxidase activity in mice.

     

Haemoglobin in male Daphnia magna

• 1.1. To define the respiratory function of haemoglobin in male Daphnia magna, the swimming activity, the depression of oxygen uptake by treatment with carbon monoxide and in vivo oxygenation of Hb at various oxygen pressures were investigated.
• 2.2. The P₅₀, values for the purified Hbs from male and female red animals were 2.0 and 2.7 torr in 0.1 M phosphate buffer (pH 7.2) at 20°C, respectively.
• 3.3. The isoelectric focusing patterns of the purified Hbs from male and female red animals showed only small differences in Hb components of high PI values.

     

Tissue specific isoenzymes of d-lactate dehydrogenase from the foot,mantle and hepatopancreas of Patella caerulea (L). purification and properties

• 1.1. Isoenzymes of d-lactate specific dehydrogenase from foot, mantle and hepatopancreas of Patella caerulea have been purified by Chromatographic techniques. d-lactate dehydrogenase (d-Ldh) from P. caerulea tissues was found to be tetrameric with a M_r of ca 140,000 as judged by gel filtration; subunit M_r of ca 37,000 was obtained from SDS-electrophoresis.
• 2.2. Kinetic studies suggest that P. caerulea foot and mantle d-Ldh is similar to vertebrate muscle-type l-Ldh; furthermore hepatopancreas d-LDH resembles vertebrate heart-type l-LDH since it has a higher affinity for d-lactate and is inhibited by pyruvate.
• 3.3. The results imply that the P. caerulead-Ldh isoenzymes may have distinct metabolic functions.

     

Yolk synthesis in the marine shrimp,Penaeus vannamei

• 1.1. In vitro yolk synthesis was measured in fragments of the ovary of developing shrimp, Penaeus vannamei.
• 2.2. Progesterone and estradiol stimulated yolk synthesis in vitro, while ecdysterone, testosterone and estrogen had no effect.
• 3.3. A peptide factor from the eyestalks of crayfish stimulated yolk synthesis in vitro. A peptide factor from shrimp eyestalks inhibited yolk synthesis in vitro.

     

Protein characterization of sexually mature and immature forms of Schistosoma mansoni

• 1.1. Protein composition of different stages of Schistosoma mansoni was compared using specific antisera, 2D polyacrylamide gel electrophoresis and 14-C-leucine incorporation into proteins.
• 2.2. Major qualitative differences were detected when an anti-membrane antiserum was used.
• 3.3. 2D gel electrophoresis showed that the protein composition varied when mature and immature females were compared, whereas no differences were noted when mature and immature male worms were compared.
• 4.4. Experiments measuring protein synthesis by the different schistosome stages confirmed that upon maturation, only the female schistosomes displayed qualitative differences.
• 5.5. The protein pattern of the male schistosomes did not vary significantly as a function of development.

     

Glycogen phosphorylase in lobster hepatopancreas: action of proteases on the enzyme

• 1.1. In lobster hepatopancreas, extracellular protreases cause the inactivation of glycogen phosphorylase.
• 2.2. The proteolysis of glycogen phosphorylase purified from rabbit muscle by these proteases has been shown by SDS-polyacrylamide gel electrophoresis.
• 3.3. A cell isolation technique has allowed us to remove proteases of extracellular digestion and to measure glycogen phosphorylase activity in lobster hepatopancreas.
• 4.4. The glycogen phosphorylase activity seems to be mainly associated with R cells while it could not be detected in B cells.

     

Spingophosphonolipids in microsomes of Diplodon delodontus. Distribution and effect on the membrane microviscosity

• 1.1. The distribution of ceramide aminoethylphosphonate (CAEP) in microsomal membranes obtained from different tissues of the bivalve mollusc Diplodon delodontus was determined.
• 2.2. The concentration of CAEP reached from 9 to 19% of the total microsomal polar lipids, depending on the kind of tissue.
• 3.3. Palmitic acid was the main fatty acid in the ceramide moiety, followed by stearic and eicosamonoenoic acids.
• 4.4. Artificial membranes were prepared with microsomal phospholipids or phospholipids plus sterols, with and without the addition of CAEP.
• 5.5. It was shown that the phosphonate confers minor mobility to the membranes. This effect is more effective when the membrane contains the natural sterols and the phospholipids are unsaturated.

     

Integrated Analyses of Phenotype and Quantitative Proteome of CMTM4 Deficient Mice Reveal Its Association with Male Fertility

1. Download : Download high-res image (158KB)
2. Download : Download full-size image

Highlights

• •CMTM4 is associated with human spermatogenesis and sperm quality.
• •Cmtm4 knockout mouse were generated by CRISPR/Cas9 technology for male fertility research.
• •CMTM4 is required for male fertility but not female fertility.
• •Phenotype and quantitative proteomics of Cmtm4 KO mice reveal an association of CMTM4 with histone-to-protamine exchange, sperm motility and induction of the acrosome reaction.

     

A novel inhibitor of glycogen phosphorylase from crayfish hepatopancreas

• 1.1. A novel glycogen phosphorylase inhibitor was partially purified from crayfish hepatopancreas.
• 2.2. The inhibitor was found only in two species of crayfish examined, and not in lobster, fresh and salt water clams, mussels or cockroaches.
• 3.3. The inhibitor is a small protein (M_r = 23,000) which did not show proteolytic activity.
• 4.4. Preliminary kinetic analysis of the inhibitory mechanism indicated that it bound to both glycogen and the glycogen phosphorylase protein.
• 5.5. Inhibitor binding to glycogen resulted in a competitive inhibition pattern with respect to glycogen phosphorylase (inhibition constant of ca 10 μg/ml).
• 6.6. The inhibitor also bound glycogen phosphorylase directly with a binding coefficient of 100 μg/ml resulting in a partially non-competitive inhibition pattern with respect to phosphate.

     

Breast,hips, and buttocks revisited: Honest fatness for honest fitness

This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:

• 1.1. Sexual selection has probably not been the most important selection pressure on
• 2.female human body shape.
• 3.2. Male humans in different cultures find different aspects of the female body attractive
• 4.and therefore are unlikely to have exerted consistent directional sexual selection on
• 5.the female body.
• 6.3. Breast size is not correlated with lactation success.
• 7.4. Visible hip width is not correlated with parturition success.
• 8.5. Women would lower their fitness if they tried to deceive men about their internal
• 9.pelvic dimensions.
• 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
• 11.breast, hips, and buttocks.