scholarly journals Characteristics and biosynthesis of membrane proteins of lipid bodies in the scutella of maize (Zea mays L.)

1986 ◽  
Vol 235 (1) ◽  
pp. 57-65 ◽  
Author(s):  
R Qu ◽  
S M Wang ◽  
Y H Lin ◽  
V B Vance ◽  
A H Huang
Keyword(s):  
Zea Mays ◽  
Gel Electrophoresis ◽  
Zea Mays L ◽  
Polyacrylamide Gel Electrophoresis ◽  
Lipid Body ◽  
Lipid Bodies ◽  
Two Dimensional Gel Electrophoresis ◽  
Triton X

Storage lipid bodies, which are prominent organelles present in the storage tissues of most seeds, have not been subjected to intensive biochemical investigation. In the present studies the major proteins in lipid bodies isolated from eleven taxonomically diverse species were shown to be distinctly different, as revealed by SDS/polyacrylamide-gel electrophoresis. The lipid-body membrane of maize (Zea mays L.) contained three major proteins of low Mr (19,500, 18,000 and 16,500), and they were chosen for further study. They all had alkaline pI values and behaved as hydrophobic integral proteins, as shown by their resistance to solubilization after repeated washing, amino acid composition and partitioning in a Triton X-114 system. Labelling in vivo with [35S]methionine and translation in vitro using extracted RNA in a wheat-germ system showed that the proteins were synthesized during seed maturation and not germination. The proteins synthesized in vivo and in vitro exhibited no appreciable difference in their mobilities in two-dimensional gel electrophoresis (isoelectric focusing and molecular sieving). The most abundant protein, that of Mr 16,500, was shown to be synthesized predominantly, if not exclusively, by RNA derived from bound polyribosomes and not from free polyribosomes. The implication of the results on the biosynthesis of the lipid bodies is discussed.

In-vivo and in-vitro secretion of prolactin by lactating rat adenohypophyses as a function of intracellular age

1984 ◽  
Vol 101 (1) ◽  
pp. 27-32 ◽  
Author(s):  
F. Mena ◽  
G. Martínez-Escalera ◽  
C. Clapp ◽  
C. E. Grosvenor
Keyword(s):  
Pituitary Gland ◽  
Incubation Period ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Pituitary Glands ◽  
H 26

ABSTRACT Adenohypophysial prolactin of lactating rats was pulse-labelled by [3H]leucine injected i.v. at the time of removal of the pups. The [3H]prolactin concentration in the pituitary gland, analysed by polyacrylamide-gel electrophoresis, progressively fell as the time from labelling to removal of the pituitary gland increased from 8 to 24 h, which suggests that there was a loss of hormone as it aged within the gland. Suckling effectively provoked the depletion–transformation of total and [3H]prolactin (extracted at pH 7·2) when applied after 8 h but not when applied after either 16 or 24 h after removing the pups. In rats whose pups were removed for 8 h, suckling also depleted–transformed [3H]prolactin labelled 4 h, but not that labelled 1 h before suckling. The pituitary glands of other lactating rats were labelled with [3H]leucine injected i.v. at various times before removing the glands and incubating them in medium 199. The secretion into the medium of [3H]prolactin labelled either 4, 8, 16 or 24 h beforehand was maximal during the first 30 min then declined from 30 to 240 min of incubation. However, secretion of prolactin labelled 1 h and 10 min beforehand reached a maximum after 0·5–1 h and 2 h of incubation respectively, then remained constant during the remainder of the 4-h incubation period. The total 4-h secretion of [3H]prolactin was greatest (65% of preincubation concentration) from those glands labelled 4 h before in contrast to those labelled 10 min (15%) or 1 (38%), 8 (34%), 16 (18%) or 24 h (26%) before incubation. Taken together, these data suggest that prolactin synthesized 4 h earlier is more likely to be released in response to physiological stimuli than is more recently formed prolactin or prolactin which has remained in the pituitary gland for 16 h or longer. J. Endocr. (1984) 101, 27–32

scholarly journals The Rhodococcus opacus PD630 Heparin-Binding Hemagglutinin Homolog TadA Mediates Lipid Body Formation

2010 ◽  
Vol 76 (21) ◽  
pp. 7217-7225 ◽  
Author(s):  
Daniel P. MacEachran ◽  
M. E. Prophete ◽  
A. J. Sinskey
Keyword(s):  
Kinetic Studies ◽  
Lipid Body ◽  
Dry Weight ◽  
Rhodococcus Opacus ◽  
Lipid Bodies ◽  
Heparin Binding ◽  
Tag Biosynthesis ◽  
Tag Accumulation

ABSTRACT Generally, prokaryotes store carbon as polyhydroxyalkanoate, starch, or glycogen. The Gram-positive actinomycete Rhodococcus opacus strain PD630 is noteworthy in that it stores carbon in the form of triacylglycerol (TAG). Several studies have demonstrated that R. opacus PD630 can accumulate up to 76% of its cell dry weight as TAG when grown under nitrogen-limiting conditions. While this process is well studied, the underlying molecular and biochemical mechanisms leading to TAG biosynthesis and subsequent storage are poorly understood. We designed a high-throughput genetic screening to identify genes and their products required for TAG biosynthesis and storage in R. opacus PD630. We identified a gene predicted to encode a putative heparin-binding hemagglutinin homolog, which we have termed tadA (triacylglycerol accumulation deficient), as being important for TAG accumulation. Kinetic studies of TAG accumulation in both the wild-type (WT) and mutant strains demonstrated that the tadA mutant accumulates 30 to 40% less TAG than the parental strain (WT). We observed that lipid bodies formed by the mutant strain were of a different size and shape than those of the WT. Characterization of TadA demonstrated that the protein is capable of binding heparin and of agglutinating purified lipid bodies. Finally, we observed that the TadA protein localizes to lipid bodies in R. opacus PD630 both in vivo and in vitro. Based on these data, we hypothesize that the TadA protein acts to aggregate small lipid bodies, found in cells during early stages of lipid storage, into larger lipid bodies and thus plays a key role in lipid body maturation in R. opacus PD630.

scholarly journals Force transduction by Triton cytoskeletons

2002 ◽  
Vol 156 (4) ◽  
pp. 609-615 ◽  
Author(s):  
Yasuhiro Sawada ◽  
Michael P. Sheetz
Keyword(s):  
Focal Adhesion ◽  
Tyrosine Phosphatase ◽  
Actin Binding ◽  
Two Dimensional Gel Electrophoresis ◽  
Conformation Changes ◽  
Cytoplasmic Proteins ◽  
Ionic Mechanisms ◽  
Triton X

Force-initiated signal transduction can occur either via membrane-based ionic mechanisms or through changes in cytoskeletal–matrix linkages. We report here the stretch-dependent binding of cytoplasmic proteins to Triton X-100 cytoskeletons of L-929 cells grown on collagen-coated silicone. Triton X-100–insoluble cytoskeletons were stretched by 10% and incubated with biotinylated cytoplasmic proteins. Analysis with two-dimensional gel electrophoresis showed stretch-dependent binding of more than 10 cytoplasmic protein spots. Bound cytoplasmic proteins were purified by a photocleavable biotin tag and stretch-dependent binding of paxillin, focal adhesion kinase, and p130Cas was found, whereas the binding of vinculin was unchanged and actin binding decreased with stretch. Paxillin binding upon stretch was morphologically and biochemically similar in vitro and in vivo, that is, enhanced in the periphery and inhibited by the tyrosine phosphatase inhibitor, phenylarsine oxide. Thus, we suggest that transduction of matrix forces occurs through force-dependent conformation changes in the integrated cytoskeleton.

Identification of D-Dimer-E Complex in Disseminated Intravascular Coagulation (DIC)

1979 ◽  
Author(s):  
A.N. Whitaker ◽  
E.A. Rowe ◽  
P.P. Masci ◽  
P.J. Gaffney
Keyword(s):  
Gel Electrophoresis ◽  
Degradation Products ◽  
Polyacrylamide Gel Electrophoresis ◽  
Stable Complex ◽  
Fibrin Degradation Products ◽  
Pneumococcal Sepsis ◽  
D Antigen ◽  
D Dimer

D-dimer (D2), a product of the plasmin lysis of cross-linked (XL) fibrin, but not of non-XL fibrin or fibrinogen, has been identified in the plasma of patients with DIC due to amniotic fluid embolism. In vitro, D is involved with fragment E as a stable complex (D2-E) but D2 -E has not been identified in vivo before. Fibrin degradation products (FDP) were studied in a patient having fulminant postsplenectomy pneumococcal sepsis and DIC, by immunoprecipitation with anti-fibrinogen (f) and anti-fragment E and characterization by SDS polyacrylamide gel electrophoresis (PAGE). With both antisera soluble HMW fibrin complexes, D2 and E but no X, Y or D were obtained from serum. D2 and E were identified in the supernatant after removing partially XL HMW complexes and fibrinogen from plasma with 2.5 M β-alanine. The presence D antigen in the D2-E complex precipitated by monospecific anti-E was confirmed by crossed Ag-Ab electrophoresis. Crossed Ag-Ab electrophoresis of serum in agarose gave E peaks of slow mobility and no fast-moving free E was found. Thus, D2-E complex exists in vivo and its easy identification, proving the lysis of XL fibrin, would be of value in studying thrombosis. D2-E complex has been identified in other patients with sepsis but at lower concentrations than described above.

scholarly journals Development of a New Maize (Zea mays L.) Breeding Program

2002 ◽  
pp. 25-30
Author(s):  
Pál Pepó ◽  
Szilárd Tóth
Keyword(s):  
Zea Mays ◽  
Recurrent Selection ◽  
Zea Mays L ◽  
Genetic Manipulation ◽  
Dominant Gene ◽  
Breeding Program ◽  
Regeneration Ability ◽  
Breeding Programs

Genetic manipulation may not replace any conventional method in crop breeding programs, but it can be an important adjunct to them. Plant regeneration via tissue culture is becoming increasingly more common in monocots such as corn (Zea mays L.). In vitro culturability and regeneration ability of corn decreased as homozigosity increased, which suggested that these two attributes were controlled primarily by dominant gene action. Pollen (gametophytic) selection for resistance to aflatoxin in corn can greatly facilitate recurrent selection and screening of germplasm for resistance at a much less cost and shorter time than field testing. Integration of in vivo and in vitro techniques in maize breeding program has been developed to obtain desirable agronomic attributes, speed up the breeding process and enhance the genes responsible for them. The efficiency of anther and tissue cultures in most cereals such as maize and wheat have reached the stage where it can be used in breeding programs to some extent and many new cultivars produced by genetic manipulation have now reached the market.

scholarly journals Evaluation of the in vitro and in vivo antihypertensive effect and antioxidant activity of blue corn hydrolysates derived from wet-milling//Evaluación del efecto antihipertensivo in vitro e in vivo y actividad antioxidante del hidrolizado de maíz azul derivado de la molienda húmeda

Biotecnia ◽  
2020 ◽  
Vol 22 (2) ◽  
pp. 155-162 ◽  
Author(s):  
Alvaro Montoya-Rodríguez ◽  
Evelyn Isabel Osuna-Gallardo ◽  
Francisco Cabrera-Chávez ◽  
Jorge Milán-Carrillo ◽  
Cuauhtémoc Reyes-Moreno ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Antioxidant Activity ◽  
Zea Mays ◽  
Antihypertensive Effect ◽  
Zea Mays L ◽  
Enzymatic Digestion ◽  
Wet Milling ◽  
Food Ingredient

Hypertension is considered a risk factor for coronary heart disease, and its prevalence has increased substantially. Inhibition of angiotensin-converting enzyme (ACE-I) is key to lower blood pressure, making it an excellent treatment for hypertension. Corn (Zea mays L.) is an important source of bioactive peptides with potential anti-hypertensive activity related to ACE-I inhibition. These peptides can be obtained through the hydrolysis of corn gluten meal (CGM), as wetmilling by-products. The aim was to evaluate the in vitro and in vivo ACE-I inhibitory activity of blue CGM hydrolysates. Enzymatic digestion in vitro of blue CGM was conducted at different times. Hydrolysis for 360 min significantly increased both soluble protein and antioxidant activity by 4 and 8-fold respectively, the maximum ACE-I inhibition (94.3 %) was observed with 260 min hydrolysate. Mice were treated with the blue CGM hydrolysate (260 min), captopril or PBS to test the bioavailability in vivo. The CGM hydrolysate was detected in serum after 5 and up to 30 min after ingestion, showing the maximum ACE-I inhibitory capacity (59 %) during the first 15 min. Overall, this work showed that the blue CGM hydrolysate could serve as a functional food ingredient with antihypertensive effect due to its blood pressure-lowering peptides.RESUMENLa hipertensión es factor de riesgo en enfermedades coronarias, y su prevalencia ha aumentado sustancialmente. La inhibición de enzima convertidora de angiotensina (ECA) es clave para disminuir presión arterial, y excelente tratamiento para hipertensión. El maíz (Zea mays L.) es fuente de péptidos bioactivos con actividad antihipertensiva por inhibición de ECA. Péptidos pueden obtenerse por hidrólisis de harina de gluten de maíz (HGM), como subproducto de molienda húmeda. El objetivo fue evaluar in vitro e in vivo actividad inhibitoria de ECA en hidrolizados de HGM azul. La digestión enzimática in vitro de HGM fue conducida a diferentes tiempos. La hidrólisis por 360 min aumento significativamente proteína soluble y actividad antioxidante de 4 y 8 veces, respectivamente; la máxima inhibición de ECA (94.3 %) fue observada a 260 minutos del hidrolizado. Ratones fueron tratados con HGM hidrolizado (260 minutos), captopril o PBS para evaluar biodisponibilidad in vivo. Después de la ingestión, HGM hidrolizado fue detectado en suero en 5 hasta 30 minutos, mostrando máxima inhibición de ECA (59 %) durante los primeros 15 minutos. En general, este trabajo mostró que hidrolizado de HGM podría servir como ingrediente funcional en alimentos con efecto antihipertensivo debido a péptidos reductores de presión arterial.

Studies of the Metabolism of Asialotransferrins: Evidence that Transferrin Does not Undergo Desialylation in Vivo

1974 ◽  
Vol 46 (6) ◽  
pp. 763-774
Author(s):  
K.-L. Wong ◽  
P. A. Charlwood ◽  
M. W. C. Hatton ◽  
E. Regoeczi
Keyword(s):  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Biological Significance ◽  
Polyacrylamide Gel ◽  
Fractional Catabolic Rate ◽  
Sialic Acid Content ◽  
Catabolic Rate ◽  
Bovine Transferrin

1. Experiments are reported which aimed at determining whether transferrin loses sialyl residues from the carbohydrate side-chains during the biological lifetime of the molecule. To explore this possibility, transferrin fractions of relatively high sialic acid content (referred to as sialotransferrin) were prepared from purified rabbit and bovine transferrin by preparative polyacrylamide-gel electrophoresis. After labelling with 125I, the preparations were injected into a group of three rabbits each. From the plasma samples obtained between 1 h and 6–8 days after injection, transferrin was partially purified, mixed with 131I-labelled asialotransferrin of the corresponding species and run in preparative polyacrylamide-gel electrophoresis. In each specimen examined, the 125I radioactivity migrated ahead of the marker asialotransferrin, and no portion of the dose was detected with the electrophoretic mobility of asialotransferrin. 2. Evidence is presented that bovine transferrin desialylated in vitro remains detectable in the plasma of rabbits for intervals which are comparable with those found in previous studies with rabbit asialotransferrin. 3. A mathematical model is described for the computation of asialo- to sialotransferrin radioactivity ratios in the plasma, continuous desialylation of pulse-injected sialotransferrin being assumed. Calculations were made at various hypothetical rates of desialylation. 4. On the basis of the experimental data and the model it is concluded that transferrin (both rabbit and bovine) is not subjected to systematic desialylation in rabbits. Random desialylation of some transferrin could take place at rates less than 5% of the fractional catabolic rate of transferrin, which would be without any biological significance.

EFFECTS OF GONADOTROPHINS AND CYCLIC 3′,5′-AMP ON IN VITRO INCORPORATION OF [3H]URIDINE INTO RNA OF THE PREPUBERTAL RAT OVARY

1973 ◽  
Vol 72 (4) ◽  
pp. 771-785 ◽  
Author(s):  
Jan Jarlstedt ◽  
Lars Nilsson ◽  
Lars Hamberger ◽  
Kurt Ahrén
Keyword(s):  
Cyclic Nucleotide ◽  
Gel Electrophoresis ◽  
Incubation Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Labelling Pattern ◽  
Total Rna ◽  
Rat Ovary ◽  
Prepubertal Rats

ABSTRACT In vivo and in vitro effects of FSH and LH on in vitro incorporation of [3H]uridine into RNA of the prepubertal rat ovary have been studied. RNA was fractionated with composite agarose-polyacrylamide gel electrophoresis. When FSH was injected into the prepubertal rats 4 h before incubation of the ovaries, the incorporation of labelled uridine into total RNA was decreased showing relatively more radioactivity concentrated to the RNA fractions lighter than 28S as compared to the controls. These effects were not seen when FSH was added to the incubation medium in vitro. When LH was added in vitro to the isolated ovaries a higher percentage of incorporated radioactivity was concentrated in the RNA fractions heavier than 28S without any change in the incorporation of [3H]uridine into total RNA. LH administered in vivo 30 min before incubation of the ovaries gave the same change in the labelling pattern between the RNA fractions as LH in vitro but in addition showed a decreased incorporation of radioactivity into total RNA. The in vitro effects of cyclic 3′,5′-AMP were also studied. When prepubertal rat ovaries were incubated in 10 mmol/l of this cyclic nucleotide, the incorporation of [3H] uridine into total RNA was decreased without any change in the labelling pattern.

Assessment of heterosis proteins in maize (Zea mays L.) leaves by two-dimensional gel electrophoresis

Plant Gene ◽  
2021 ◽  
pp. 100331
Author(s):  
Ali Bandehagh ◽  
Zahra Dehghanian ◽  
Sajjad Moharramnejad ◽  
Shiva Aliyari Rad ◽  
Shahram Shirmohammadi ◽  
...  
Keyword(s):  
Zea Mays ◽  
Gel Electrophoresis ◽  
Zea Mays L ◽  
Two Dimensional ◽  
Two Dimensional Gel Electrophoresis
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