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PubMed1992

Dietary fat and fatty acids modulate cholesterol cholelithiasis in the hamster.

We tested two hypotheses, i) whether the type and the amount of fat in the diet will affect the formation of cholesterol gallstones in the hamsters, and ii) whether palmitic acid, a major fatty acid component of butterfat, can act as a potentiator of cholesterol cholelithiasis in the hamster. Young, male golden Syrian hamsters (Sasco) were fed a semipurified diet containing casein, corn starch, cellulose and cholesterol (0.3%) to which various types and amounts of fat (butterfat, olive oil, menhaden oil, corn oil) were added. All diets contained 2% corn oil to supply essential fatty acids to the growing hamsters. No deaths or illness occurred during the experiment. Animals fed the semipurified diet plus 4% butterfat (group 1) had a gallstone incidence of 63%. Replacement of butterfat with either olive oil, corn oil or menhaden oil prevented the formation of cholesterol gallstones entirely (groups 2-4). When total butterfat was increased from 4% to 8% (group 8), the incidence of cholesterol gallstones increased to 80%. Substitution of 4% olive oil (group 5), corn oil (group 6), or menhaden oil (group 7) for the additional 4% butterfat significantly reduced gallstones to 35%, 45% and 30%, respectively. The replacement of 4% butterfat with 1.2% palmitic acid gave the highest incidence of cholesterol gallstones (95%). These results suggest that butterfat (and one of its components, palmitic acid) intensifies gallstone formation in this model whereas mono- and polyunsaturated fats act as inhibitors of cholesterol cholelithiasis. A fatty acid, possibly palmitic acid, appears to act as lithogen in our model.

Animals↗

PubMed1995

5-Bromomethyl fluorescein (5-BMF) for derivatization of carboxyl containing analytes for use with laser-induced fluorescence detection.

PURPOSE: 5-Bromomethyl fluorescein (5-BMF) was evaluated in this work as a pre-column, off-line derivatizing reagent for analytes containing a free carboxyl group. The reagent possessed high molar absorptivity and quantum yield and it's excitation maximum matched the intense 488.0 nm emission line of an argon ion laser. The thermal and photo-stability of the reagent were also suitable for our work. METHODS: A mixture of 5-BMF, palmitic acid, 18-crown-6 and potassium carbonate was reacted at 76 degrees C for one hour. The reaction yield was maximized by a sequential single-factor optimization of the reaction variables. Spectral characterizations were accomplished using conventional instrumentation and detection limits were evaluated using a laboratory constructed laser-induced fluorescence (LIF) detector which was optimized for concentration detection. RESULTS: Two apparent conjugates of palmitic acid were formed under the reaction conditions employed. The conjugate chosen for quantitative purposes was stable at room temperature over 24 hours and possessed high molar absorptivity (128,832 M-1cm-1) and quantum yield (0.82) under basic conditions. The excitation and emission maxima of the conjugate were 500 nm and 523 nm respectively which maintains suitability for argon-ion laser excitation. An argon-ion LIF detector suitable for use with conventional liquid chromatography was constructed. A detection limit of 7.56 x 10(-10)M of palmitic acid was achieved at a signal to noise ratio of three, using the strong 488.0 nm laser emission line and a commercially available flow cell component. This corresponds to 38 femtomoles of palmitic acid on-column. CONCLUSION: The concentration detection limit was superior to literature reports for detection of fatty acids. The mass detection limit provided approximately an order of magnitude improvement over conventional fluorescence. The reagent is potentially useful for analysis of carboxyl containing analytes at low concentrations.

Carboxylic Acids↗

PubMed2002

Diabetes causes marked changes in lymphocyte metabolism.

An enhanced susceptibility to infections is well known to occur in a poorly controlled diabetic state. Since glucose and glutamine are essential for lymphocyte function, we investigated whether their metabolism is changed in lymphocytes obtained from mesenteric lymph nodes of alloxan-induced diabetic rats (40 mg/kg body weight). The activities of hexokinase, phosphofructokinase, glucose-6-phosphate dehydrogenase (G6PDH), citrate synthase and phosphate-dependent glutaminase were determined. Decarboxylation of metabolites [U-14C]-, [1-14C]- and [6-14C]-glucose, [1-14C]- and [2-14C]-pyruvic acid, [U-14C]-palmitic acid and [U-14C]-glutamine was evaluated in incubated lymphocytes isolated from mesenteric lymph nodes. The measurements were carried out in cells following three experimental protocols: (1) lymphocytes freshly obtained from control and alloxan-induced diabetic rats, (2) lymphocytes from insulin-treated (2 U/rat per day) diabetic rats and (3) lymphocytes obtained from control and diabetic rats and cultured in the presence of insulin (1 mU/ml) for 6 h. The activities of hexokinase, G6PDH and citrate synthase were decreased by the diabetic state, whereas that of phosphofructokinase was raised. Decarboxylation of [U-14C]- and [6-14C]-glucose, [1-14C]- and [2-14C]-pyruvate and [U-14C]-glutamine were also decreased in lymphocytes from diabetic rats, whereas [U-14C]-palmitic acid decarboxylation was increased. Insulin administration in vivo or added to the culture medium reversed the changes observed in freshly obtained lymphocytes. Alloxan-induced diabetes did change lymphocyte metabolism and this may be an important mechanism leading to impairment of lymphocyte function.

Animals↗

PubMed1996

Specificities of red cell membrane sites transporting three long chain fatty acids.

We studied the specificities of human red cell membrane bindings of three long chain fatty acids, palmitic- arachidonic- and oleic acid, using resealed membranes, ghosts. Previously estimated binding capacities, affinities and inside/outside distributions suggest separated binding sites. This possibility is explored by estimating the binding properties of one fatty acid in the presence of one or two of the others. Binding capacities, nmol g-1 ghosts, of palmitic and arachidonic acid estimated simultaneously vs. separately are 27.4 +/- 2.7 vs. 29.0 +/- 2.1 (P < 0.6) and 6.5 +/- 0.6 vs. 5.5 +/- 0.5 (P < 0.2) respectively. The corresponding estimates for oleic- and palmitic acid are 36.5 +/- 2.0 vs. 34.0 +/- 2.2 (P < 0.4) and 28.4 +/- 1.8 versus 29.1 +/- 2.1 (P < 0.8). The binding sites are therefore independent. For each of the three fatty acids in the absence or in the presence of one or two of the others, the inside/outside distributions of the binding sites and the membrane transfer rate constants are elucidated by exchange efflux kinetics at 0 degrees C from ghosts with and without enclosed albumin. Packed ghosts loaded with radioactive acids are injected rapidly into a large volume of vigorously stirred buffer with albumin. With a resolution time of about 1-sec serial filtered ghost-free aliquots are collected and counted. The analyses show that palmitic- and oleic acid sites of transport are entirely independent but do not exclude that palmitic- and/or oleic acid binding may diminish the arachidonic acid affinity a little. The diversity combined with specificity suggests that the transport sites for long chain fatty acids are protein-determined microdomains of phospholipids.

Biological Transport↗

PubMed1988

Cation-independent mannose 6-phosphate receptor contains covalently bound fatty acid.

The cation-independent mannose 6-phosphate receptor (215,000 daltons) was isolated from embryonic bovine tracheal cells and embryonic human skin fibroblasts labelled with [3H]palmitic acid. The tritium label was detected in the protein upon fluorographic analysis of SDS-polyacrylamide gels of the purified receptor. The label was not sensitive to hydroxylamine, methanolic KOH, or beta-mercaptoethanol, but labelled fatty acid was recovered from the protein by acidic methanolysis. Labelled receptor protein could not be isolated from cells grown in the presence of [3H]myristic acid. The results suggest the presence of amide-linked palmitic acid in the structure of the cation-independent mannose 6-phosphate receptor.

Animals↗

PubMed1998

Retainment of membrane binding capacity of non-palmitoylated Gs alpha mutants expressed in COS-1 cells.

Heterotrimeric guanine nucleotide binding regulatory proteins (G proteins) transduce extracellular signals into intracellular signals by coupling receptors and effectors. Because most of the G protein-coupled receptors are integral proteins, the G proteins need to have a membrane binding capacity to receive signals from the receptors. The alpha subunit of G protein binds tightly to the cytoplasmic face of the plasma membrane without any membrane spanning domain. Fatty acylation of G alpha with myristic acid or palmitic acid, in addition to the beta gamma subunits, plays an important role in anchoring the G alpha subunit. The reversible and dynamic palmitoylation of the alpha subunit of stimulatory G protein (Gs alpha) has been suggested as essential for its membrane attachment. However, in our previous experiments, Gs alpha deleted in the amino terminus containing palmitoylation site, retained its binding capacity when expressed in COS cells. Thus, to evaluate the role of palmitoylation in Gs alpha membrane binding, we constructed and expressed non-palmitoylated mutants of Gs alpha and analyzed their subcellular distributions in COS-1 cells. We found that non-palmitoylated mutants of Gs alpha, C3S- and G2A/C3S Gs alpha, retained their membrane binding capacities in COS-1 cells, demonstrating that palmitoylation is not essential for membrane binding of Gs alpha in COS-1 cells. We also found that the palmitoylation did not change significantly the distribution of Gs alpha in Triton X-114 partition. These results suggest that the palmitoylation of Gs alpha may produce different effects on membrane binding depending on cell types.

Animals↗

PubMed2004

Characterization of triacylglycerols from overwintering prepupae of the alfalfa pollinator Megachile rotundata (Hymenoptera: Megachilidae).

Alfalfa leafcutting bees, Megachile rotundata (F.), overwinter as prepupae. The internal lipids were extracted from prepupae that had been wintered at 4 degrees C for 7 months. Megachile rotundata prepupae possessed copious quantities of internal lipids (20% of the fresh weight) that were extracted with CHCl3/methanol (2:1). Transmission electron microscopy revealed that lipids were stored within very large intracellular vacuoles. Separation by silica chromatography revealed that 88% of the internal lipids were triacylglycerols. Ester derivatives of fatty acids from triacylglycerol components were analyzed by gas chromatography-mass spectrometry and 15 fatty acid constituents were identified. The majority (76%) of the triacylglycerol fatty acids were unsaturated fatty acids. The major triacylglycerol fatty acid constituent (30%) was the C16 monounsaturated fatty acid, palmitoleic acid (16:1, hexadec-9-enoic acid), with substantial amounts of linolenic acid (18:3, octadec-9,12,15-trienoic acid, 15%), palmitic acid (16:0, hexadecanoic acid, 14%) and oleic acid (18:1, octadec-9-enoic acid, 13%). Palmitoleic acid as the major fatty acid of an insect is an unusual occurrence as well as the presence of the 16-carbon polyunsaturated fatty acids, 16:2 and 16:3. The major intact triacylglycerol components were separated and identified by high performance liquid chromatography-mass spectrometry. A complex mixture of approximately 40 triacylglycerol components were identified and major components included palmitoyl palmitoleoyl oleoyl glycerol, palmitoyl palmitoleoyl palmitoleoyl glycerol, myristoyl palmitoleoyl palmitoleoyl glycerol, myristoleoyl palmitoyl palmitoleoyl glycerol, and palmitoyl palmitoleoyl linolenoyl glycerol. The function of these internal lipids and their relevance to winter survival and post-wintering development of M. rotundata is discussed.

Animals↗

PubMed2003

Method development for the analysis of trans-fatty acids in hydrogenated oils by capillary electrophoresis.

A novel capillary electrophoresis methodology using UV indirect detection (224 nm) for the analysis of trans-fatty acids in hydrogenated oils was proposed. The electrolyte consisted of a pH 7 phosphate buffer at 15 mmol x L(-1) concentration containing 4 mmol.L(-1) sodium dodecylbenzenesulfonate, 10 mmol x L(-1) polyoxyethylene 23 lauryl ether (Brij 35), 2% 1-octanol and 45% acetonitrile. Under the optimized conditions, ten fatty acids, C12:0, C13:0 (internal standard), C14:0, C16:0, C18:0, C18:1c, C18:1t, C18:2cc, C18:2tt and C18:3ccc were baseline-separated in less than 12 min. The proposed methodology was applied to monitor the formation of trans-fatty acids during hydrogenation of Brazilnut oil. A crude oil sample (42.1% linoleic acid, 37.3% oleic acid, 13.4% palmitic acid, and 7.0% stearic acid) was mixed with 0.25% of a nickel-based catalyst and submitted to two independent hydrogenation conditions: 175 degrees C, 3 atm, 545 rpm for 60 min (GH(1) sample), and 150 degrees C, 1 atm, 545 rpm for 30 min (GH(2) sample). For the most severe hydrogenation condition (higher temperature and pressure, under longer reactional period), a more complete conversion of linoleic and oleic acids into stearic acid occurred with concomitant formation of the trans-species, elaidic acid (C18:1t). For the milder hydrogenation procedure that generated sample GH(2), larger amounts of linoleic and oleic acids remained, in addition to the transformations already observed in the GH(1) sample.

Electrophoresis, Capillary↗

PubMed1995

Erythrocyte membrane fatty acid profile in patients with primary carcinoma of the gallbladder.

Erythrocyte fatty acids were determined in patients with gall stones and carcinoma of the gallbladder. Significantly low levels of myristic acid (P < 0.01) and stearic acid (P < 0.001) and significantly high levels of palmitoleic acid (P < 0.05) and oleic acid (P < 0.01) were observed in cancer patients. Arachidonic and linolenic acid were significantly high in gallstone patients, but there was no significant difference in the lauric acid and palmitic acid levels. Thus an altered lipid metabolism in cancer patients suggest existence of a possible association between gallstones, fatty acids, and carcinoma of the gallbladder.

Cholelithiasis↗

PubMed2005

The synthesis of internal standards for the quantitative determination of sphingolipids by tandem mass spectrometry.

Novel internal standards have been synthesised for the quantitative determination by tandem mass spectrometry (MS/MS) of the sphingolipids that accumulate in lysosomal storage diseases. The [d4]C16- and [d47]C24-isoforms of galactosylceramide (CMH), lactosylceramide (CDH), globotriaosylceramide (CTH), cerebroside sulphate, sphingomyelin and G(M1)-, G(M2)- and G(M3)-gangliosides were synthesised by the reaction of their lyso-forms with the acid chlorides of hexadecanoic 5,5,6,6-d4 acid ([d4]-palmitic acid) and tetracosanoic-d47 acid ([d47]-lignoceric acid), respectively. The acid chlorides were formed using oxalyl chloride. The structures of the internal standards were confirmed by MS/MS. The fragmentation pattern of each novel compound was similar to that of the corresponding natural form of the sphingolipid, making it a good internal standard for the quantitative determination of the natural sphingolipid by ESI-MS/MS. Characteristic product ions were identified for each compound.

Lysosomal Storage Diseases↗

PubMed1995

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia: 2: Chemical composition and microflora of samh seeds.

The chemical composition of samh seeds have been investigated. Proximate analysis showed a composition of 22.25% protein, 5.7% moisture, 5.6% fat, 4.0% ash, 9.7% crude fiber, and the remainder being total carbohydrates. Mineral element analysis revealed that potassium, magnesium, sodium and calcium were present as the major elements. Iron, manganese, zinc and copper were found at lower levels. However, lead was not detected in the samh seeds. Gas-liquid chromatographic analysis of the methylester of the fatty acids of the samh seeds oil revealed the presence of fourteen fatty acids. Linoleic and oleic acids were the principle unsaturated fatty acids. While palmitic acid was the main saturated fatty acid. Amino acid analysis of the samh seeds showed the presence of seventeen amino acids including eight essential amino acids. Glutamic acid, arginine, and aspartic acid were the major amino acids. Cystine and proline were present in trace amounts. These results some of which have not been reported elsewhere indicate the high nutritional potential of Saudi samh seeds. The total aerobic bacterial count and total sporeformers of seeds were 19 x 10(7) and 5 x 10(4) cfu/g respectively, thus the enterobacteriaceae, B cereus and yeast and molds were 5 x 10(2), 1 x 10(2) and 7 x 10(2) respectively. The seeds were Staph. free and the samh extract had no antimicrobial effect.

Bacteria, Aerobic↗

PubMed1988

Identification of lipid components of human serum lipoproteins involved in the inhibition of Sindbis virus infectivity, hemagglutination, and hemolysis.

Human serum high density lipoproteins (HDL), low density lipoproteins (LDL) and very low density lipoproteins (VLDL) were isolated and tested for their ability to inhibit Sindbis virus infectivity, hemagglutination and hemolysis. VLDL and LDL produced a strong reduction on both viral infectivity on Vero cell monolayers and attachment and fusion with erythrocytes, whereas HDL appeared to be only a weak inhibitor. Lipid and protein components were extracted from each class of lipoproteins to identify the molecules responsible for the inhibiting activity. Only the lipid moiety was found to inhibit Sindbis virus biological activities. Among the individual lipid components of lipoproteins, neutral lipids (cholesterol, oleic acid and palmitic acid) and negatively charged phospholipids (phosphatidylserine and phosphatidylinositol) and glycolipids (GM 3 ganglioside and cerebroside sulphate) were able to neutralize the virus suggesting that either hydrophobic or electrostatic interactions are involved in the inhibition.

Apoproteins↗

PubMed1990

The effect of endotoxin on membrane fatty acid composition in BCG-sensitized mice.

The effects of endotoxin on mouse liver phospholipid fatty acid composition have been investigated. Administration of endotoxin from Salmonella abortus equi led to a decrease in the polyunsaturated fatty acid content of livers from mice sensitized with Bacille Calmette Guérin (BCG). The content of arachidonic acid fell significantly in both the phosphatidylcholine and phosphatidylinositol fractions whereas in the phosphatidylethanolamine fraction the linoleic acid content was significantly reduced. The polyunsaturated fatty acids were replaced by increased amounts of oleic acid and palmitic acid, leading to a reduction in the polyunsaturated to saturated fatty acid ratio.

Animals↗

PubMed1992

The biochemical composition and nutritional potential of the tribal pulse, Mucuna monosperma DC. ex Wight.

Two germplasms of the tribal pulse, Mucuna monosperma Dc. ex Wight, viz., Thirunelly Reserve Forest, Wynaad District (Kerala) and Siruvani Reserve Forest, Coimbatore District (Tamilnadu), were analysed for proximate composition, total (true) seed proteins, seed protein fractionation, amino acid composition, fatty acids, minerals and anti-nutritional factors. Crude proteins, crude lipids, ash and nitrogen free extractives constituted 23.10%, 4.36%, 3.80%, 61.74%, respectively, in Tamilnadu germplasm; whereas, in Kerala germplasm they constituted 20.13%, 8.99%, 3.60% and 61.69%, respectively. The calorific values of 100 g dry matter of seed material are 408.19 KCal (Kerala) and 378.60 KCal (Tamilnadu) germplasms. Essential amino acids like methionine, cystine, threonine and valine were found to be limiting in the seed proteins of both the germplasms. The fatty acids like lauric acid and palmitic acid are found to be common in both the germplasm seed samples, while linoleic and oleic acids in Kerala germplasm and stearic acid in Tamilnadu germplasm are present. The Tamilnadu germplasm seems to be a rich source of sodium, magnesium, zinc, manganese, copper and iron; whereas the Kerala germplasm seems to be a rich source of phosphorus. Antinutritional substances like total free phenols, tannins, L-DOPA, trypsin inhibitor activity and phytohaemagglutinating activity also were investigated.

Amino Acids↗

PubMed1988

Isolation and chemical composition of surface-active material from human lung lavage.

Surface-active material (SF) was isolated from human lung lavage fluid collected at autopsy employing differential and sucrose density gradient centrifugation. The isolated material showed well-defined electron microscopic structure, consisting of clearly preserved, closely packed vesicles with limiting membranes and inclusion bodies. It showed a very high degree of alkaline phosphatase specific activity and was devoid of other subcellular contaminants. The isolated material also showed a high phospholipid/protein ratio and increasing surface activity when monitored at different stages of purification. It contained 68.5% phosphatidylcholine, 11.5% phosphatidylglycerol and relatively smaller amounts of phosphatidylethanolamine and other individual phospholipid (PL) classes. In addition, cholesterol, unesterified fatty acids, triacylglycerols and other neutral lipids were found. Saturated fatty acids, particularly palmitic acid (16:0), predominated in the major PL fractions. However, various fatty acids of which oleic acid (18:1) constituted a large proportion also are present. Chemical analysis of the material showed that besides lipids and proteins, nucleic acids, sialic acid, hexose, amino sugars, nitrogen and phosphorus were present. The delipidated material showed the presence of three to four proteins as characterized by sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis, and gel permeation chromatography on Sephadex G-200 resolved two well-separated peaks. The first fraction contained serum-associated 68 kDa protein, while the second fraction had two apoproteins with molecular weights of 34 kDa and 10 kDa. These two proteins were associated with the SF and they, as well as the whole surface-active material, strongly reacted with the antibody directed against the whole SF in a double-diffusion immunoprecipitation assay.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Farnesylamine: an inhibitor of farnesylation and growth of ras-transformed cells.

Farnesylamine, an analogue of farnesol, was shown to inhibit growth of PAP2 cells (ras-transformed NIH 3T3 cells) in a dose-dependent manner. This inhibition was overcome by adding farnesol to the culture medium, but not by adding geranylgeraniol, squalene, cholesterol, dolichol, myristic acid or palmitic acid. Farnesylamine inhibited both farnesyl/protein transferase and geranylgeranyl/protein transferase in whole cell extracts and also inhibited the prenylation of proteins, particularly ras p21, in PAP2 cells. Inhibition of prenylation was associated with increased biosynthesis of other products of the mevalonate biosynthetic pathway. These observations suggest that inhibition of the growth of PAP2 cells by farnesylamine may be due to blocking of ras-mediated signal transduction. This offers a means of investigating mechanisms involved in ras action and raises the possibility of developing novel strategies for anticancer therapy.

3T3 Cells↗

PubMed2000

Selective acylation of plasma membrane proteins of Mycoplasma agalactiae: the causal agent of agalactia.

Revealed by in vivo labeling with (14)C-palmitic acid, about 15 acylated proteins were identified in the plasma membrane of Mycoplasma agalactiae (type strain PG2), including the major component p40. Triton X-114 phase partitioning and Western blotting demonstrated the amphiphilic properties of the acyl proteins and showed that they were also antigenic components. Chemical analyses of fatty acids bound to proteins revealed the following selectivity order within acylation: stearic acid (18:0) > linoleic acid (18:2c) approximately palmitic acid (16:0) > oleic acid (18:1c) > myristic acid (14:0), with 16:0 and 18:1c preferred for the O-acylation and 18:0 for the N-acylation. The ratio [O-ester- + amide-bound acyl chains]/O-ester-linked chains being close to 1.4 as well as the presence of S-glycerylcysteine suggest that acyl proteins in M. agalactiae are true lipoproteins containing N-acyl diacyl glycerylcysteine, probably processed by a mechanism analogous to that described for Gram-negative eubacteria.

Acylation↗

PubMed2000

Characterization of inositol phospholipids and identification of a mastoparan-induced polyphosphoinositide response in Tetrahymena pyriformis.

The unicellular eukaryote Tetrahymena is a popular model for the study of lipid metabolism. Less attention, however, has been given to the inositol phospholipids of the cell, although it is known that this class of lipids plays an important role in eukaryotic cell signaling. Tetrahymena pyriformis phosphatidylinositol was isolated, purified, and characterized by proton nuclear magnetic resonance analysis and [2-(3)H]myoinositol labeling. Labeling was also used for polyphosphoinositide (phosphatidylinositol phosphate and phosphatidylinositol bisphosphate) identification. Tetrahymena inositol phospholipids were found to belong to the diacylglycerol group, although major Tetrahymena phospholipids, phosphatidylcholine and aminoethylphosphonoglycerides, have been found to be mainly alkylacylglyceroderivatives. Further characterization of Tetrahymena phosphatidylinositol by gas chromatographic analysis indicated that 80% of fatty acids were myristic acid and palmitic acid. This is also in contrast to the fatty acid profile of Tetrahymena phosphatidylcholine and phosphatidylethanolamine, with respect both to the fatty acid length and degree of unsaturation, and may indicate that specific diacylglycerol species are connected with the phosphatidylinositol metabolism in this cell. Treatment of [3H]inositol-labeled Tetrahymena cells with mastoparan, a G-protein-activating peptide, induced changes in the polyphosphoinositide levels, suggesting that inositol phospholipids may form in Tetrahymena a functional signaling system similar to that of higher eukaryotes. Addition of 10 microM mastoparan resulted in a rapid and transient increase in [3H]phosphatidylinositol phosphate followed by a decrease in [3H]phosphatidylinositol bisphosphate. Similar changes in lipids have been reported when phosphoinositide-phospholipase C pathway is activated in both animal and plant cells.

Animals↗