Adipocyte differentiation-related protein is secreted into milk as a constituent of milk lipid globule membrane

Milk lipid globules from humans, cows and rats contained a protein identified as adipocyte differentiation-related protein (ADRP) associated with the globule surface membrane material. This protein, previously believed to be specific to adipocytes, was a major constituent of the globule surface and was present in a detergent-insoluble complex that contained stoichiometric amounts of butyrophilin and xanthine oxidase. Identification of ADRP was by sequence similarity of tryptic peptides from cow and human proteins with the sequence inferred from the cDNA for mouse ADRP. The putative ADRP of lipid globules from cow, human and rat milk was recognized specifically by antisera raised against a peptide synthesized to duplicate the N-terminal 26 residues of the mouse protein. In homogenates of lactating mammary gland, ADRP was found only in endoplasmic reticulum and in lipid droplet fractions. ADRP was modified, apparently post-translationally, and one modification apparently was acylation, primarily with C14, C16 and C18 fatty acids. Two isoelectric variants of ADRP were present in cow globule membrane material. In vitro, ADRP served as a substrate for protein kinases associated with milk lipid globule membrane, but this protein did not seem to become phosphorylated intracellularly.

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Expression in non-lens tissues of an enzyme activity related to the ‘lens-specific’ protein, delta crystallin

Development ◽

10.1242/dev.111.1.181 ◽

1991 ◽

Vol 111 (1) ◽

pp. 181-190

Author(s):

D.I. de Pomerai ◽

W.K. Ip ◽

M. McLaughlin ◽

K.C. Perry

Keyword(s):

Ectopic Expression ◽

Molecular Size ◽

Protein Band ◽

Major Constituent ◽

Lens Protein ◽

Related Protein ◽

Structural Protein ◽

Cycle Enzyme ◽

Published Evidence

When chick embryo neutral retina (NR) cells are cultured for long periods in vitro, they undergo extensive transdifferentiation into lens and express the lens protein, delta crystallin. We now demonstrate that this process is accompanied by a change in the chromatin conformation of the delta-gene locus from DNAase1-resistant to DNAase1-sensitive in the nuclei of most cells. Transcripts hybridising to a delta probe are also much more prevalent among the in vitro transcription products from lens or transdifferentiated NR culture nuclei, as compared to nuclei from fresh NR tissue. Published evidence indicates that the chick delta 1 crystallin gene encodes the major structural protein of embryonic lens fibres, whereas the closely related delta 2 gene may encode the urea-cycle enzyme argininosuccinate lyase (ASL). Our present data lends further support to this view. Both immunodetectable delta-related protein(s) and ASL activity are present in fresh embryonic NR tissue, as well as in mouse and Rana liver, and in Rana lens. Our polyclonal anti-delta antibody also cross-reacts with a major constituent of commercial bovine ASL, of the same molecular size as chick delta crystallin. Immunoselection studies suggest that the ASL activity in chick embryonic NR is conferred mainly by the delta-related protein band. So-called ‘ectopic’ expression of delta crystallin in embryonic NR (and other tissues) may thus involve the delta 2/ASL gene, and could reflect some metabolic requirement for ASL activity.

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A distal region, hypersensitive to DNase I, plays a key role in regulating rabbit whey acidic protein gene expression

Biochemical Journal ◽

10.1042/bj3590557 ◽

2001 ◽

Vol 359 (3) ◽

pp. 557-565 ◽

Cited By ~ 5

Author(s):

Benjamin MILLOT ◽

Marie-Louise FONTAINE ◽

Dominique THEPOT ◽

Eve DEVINOY

Keyword(s):

Mammary Gland ◽

Sequence Similarity ◽

Distal Region ◽

Dnase I ◽

Whey Acidic Protein ◽

Acidic Protein ◽

Upstream Region ◽

Lactating Mammary Gland

The aim of the present study was to identify the functional domains of the upstream region of the rabbit whey acidic protein (WAP) gene, which has been used with considerable efficacy to target the expression of several foreign genes to the mammary gland. We have shown that this region exhibits three sites hypersensitive to DNase I digestion in the lactating mammary gland, and that all three sites harbour elements which can bind to Stat5 in vitro in bandshift assays. However, not all hypersensitive regions are detected at all stages from pregnancy to weaning, and the level of activated Stat5 detected in the rabbit mammary gland is low except during lactation. We have studied the role of the distal site, which is only detected during lactation, in further detail. It is located within a 849bp region that is required to induce a strong expression of the chloramphenicol acetyltransferase reporter gene in transfected mammary cells. Taken together, these results suggest that this region, centred around a Stat5-binding site and surrounded by a variable chromatin structure during the pregnancy–lactation cycle, may play a key role in regulating the expression of this gene in vivo. Furthermore, this distal region exhibits sequence similarity with a region located around 3kb upstream of the mouse WAP gene. The existence of such a distal region in the mouse WAP gene may explain the differences in expression between 4.1 and 2.1kb mouse WAP constructs.

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Casein kinase: the triple meaning of a misnomer

Biochemical Journal ◽

10.1042/bj20140178 ◽

2014 ◽

Vol 460 (2) ◽

pp. 141-156 ◽

Cited By ~ 67

Author(s):

Andrea Venerando ◽

Maria Ruzzene ◽

Lorenzo A. Pinna

Keyword(s):

Protein Kinases ◽

Matrix Protein ◽

Current Knowledge ◽

Sequence Similarity ◽

Casein Kinase ◽

Casein Kinase 1 ◽

Dentin Matrix Protein ◽

Lactating Mammary Gland ◽

Casein Kinases

The term ‘casein kinase’ has been widely used for decades to denote protein kinases sharing the ability to readily phosphorylate casein in vitro. These fall into three main classes: two of them, later renamed as protein kinases CK1 (casein kinase 1, also known as CKI) and CK2 (also known as CKII), are pleiotropic members of the kinome functionally unrelated to casein, whereas G-CK, or genuine casein kinase, responsible for the phosphorylation of casein in the Golgi apparatus of the lactating mammary gland, has only been identified recently with Fam20C [family with sequence similarity 20C; also known as DMP-4 (dentin matrix protein-4)], a member of the four-jointed family of atypical protein kinases, being responsible for the phosphorylation of many secreted proteins. In hindsight, therefore, the term ‘casein kinase’ is misleading in every instance; in the case of CK1 and CK2, it is because casein is not a physiological substrate, and in the case of G-CK/Fam20C/DMP-4, it is because casein is just one out of a plethora of its targets, and a rather marginal one at that. Strikingly, casein kinases altogether, albeit representing a minimal proportion of the whole kinome, appear to be responsible for the generation of up to 40–50% of non-redundant phosphosites currently retrieved in human phosphopeptides database. In the present review, a short historical explanation will be provided accounting for the usage of the same misnomer to denote three unrelated classes of protein kinases, together with an update of our current knowledge of these pleiotropic enzymes, sharing the same misnomer while playing very distinct biological roles.

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In vitro schistosomicidal activity of Usnea steineri extract and its major constituent (+)-usnic acid against Schistosoma mansoni

Planta Medica ◽

10.1055/s-0032-1320991 ◽

2012 ◽

Vol 78 (11) ◽

Cited By ~ 5

Author(s):

AIO Salloum ◽

R Lucarini ◽

MG Tozatti ◽

J Medeiros ◽

MLA Silva ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Usnic Acid ◽

Major Constituent

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A Comparison of the Effect of Decorsin and Two Disintegrins, Albolabrin and Eristostatin, on Platelet Function

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649933 ◽

1995 ◽

Vol 74 (05) ◽

pp. 1316-1322 ◽

Cited By ~ 13

Author(s):

Mary Ann McLane ◽

Jagadeesh Gabbeta ◽

A Koneti Rao ◽

Lucia Beviglia ◽

Robert A Lazarus ◽

...

Keyword(s):

Platelet Aggregation ◽

Platelet Function ◽

Sequence Similarity ◽

Platelet Aggregation Inhibitors ◽

Antiplatelet Drug ◽

Rgd Sequence ◽

Fibrinogen Receptor ◽

Activated Platelets

SummaryNaturally-occurring fibrinogen receptor antagonists and platelet aggregation inhibitors that are found in snake venom (disintegrins) and leeches share many common features, including an RGD sequence, high cysteine content, and low molecular weight. There are, however, significant selectivity and potency differences. We compared the effect of three proteins on platelet function: albolabrin, a 7.5 kDa disintegrin, eristostatin, a 5.4 kDa disintegrin in which part of the disintegrin domain is deleted, and decorsin, a 4.5 kDa non-disintegrin derived from the leech Macrobdella decora, which has very little sequence similarity with either disintegrin. Decorsin was about two times less potent than albolabrin and six times less potent than eristostatin in inhibiting ADP- induced human platelet aggregation. It had a different pattern of interaction with glycoprotein IIb/IIIa as compared to the two disintegrins. Decorsin bound with a low affinity to resting platelets (409 nM) and to ADP-activated platelets (270 nM), and with high affinity to thrombin- activated platelets (74 nM). At concentrations up to 685 nM, it did not cause expression of a ligand-induced binding site epitope on the (β3 subunit of the GPIIb/IIIa complex. It did not significantly inhibit isolated GPIIb/IIIa binding to immobilized von Willebrand Factor. At low doses (1.5-3.0 μg/mouse), decorsin protected mice against death from pulmonary thromboembolism, showing an effect similar to eristostatin. This suggested that decorsin is a much more potent inhibitor of platelet aggregation in vivo than in vitro, and it may have potential as an antiplatelet drug.

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Biological and In silico Studies on Synthetic Analogues of Tyrosine Betaine as Inhibitors of Neprilysin - A Drug Target for the Treatment of Heart Failure

Current Pharmaceutical Design ◽

10.2174/1381612824666180515114236 ◽

2018 ◽

Vol 24 (17) ◽

pp. 1899-1904

Author(s):

Daniel Fabio Kawano ◽

Marcelo Rodrigues de Carvalho ◽

Mauricio Ferreira Marcondes Machado ◽

Adriana Karaoglanovic Carmona ◽

Gilberto Ubida Leite Braga ◽

...

Keyword(s):

Heart Failure ◽

Secondary Metabolites ◽

Structural Similarity ◽

Structural Features ◽

Major Constituent ◽

Binding Modes ◽

Starting Point ◽

In Silico Studies ◽

Nep Inhibition

Background: Fungal secondary metabolites are important sources for the discovery of new pharmaceuticals, as exemplified by penicillin, lovastatin and cyclosporine. Searching for secondary metabolites of the fungi Metarhizium spp., we previously identified tyrosine betaine as a major constituent. Methods: Because of the structural similarity with other inhibitors of neprilysin (NEP), an enzyme explored for the treatment of heart failure, we devised the synthesis of tyrosine betaine and three analogues to be subjected to in vitro NEP inhibition assays and to molecular modeling studies. Results: In spite of the similar binding modes with other NEP inhibitors, these compounds only displayed moderate inhibitory activities (IC50 ranging from 170.0 to 52.9 µM). However, they enclose structural features required to hinder passive blood brain barrier permeation (BBB). Conclusions: Tyrosine betaine remains as a starting point for the development of NEP inhibitors because of the low probability of BBB permeation and, consequently, of NEP inhibition at the Central Nervous System, which is associated to an increment in the Aβ levels and, accordingly, with a higher risk for the onset of Alzheimer's disease.

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Chemical Composition and in-vitro antimicrobial screening of leaf essential oil of Plectranthus gerardianus Benth., and isolation of the major constituent of oil

The Natural Products Journal ◽

10.2174/2210315510999200731183701 ◽

2020 ◽

Vol 10 ◽

Author(s):

Navadha Bhatt ◽

Navabha Joshi ◽

Kapil Ghai ◽

Om Prakash

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Major Constituent ◽

In Vitro Antimicrobial Activity ◽

Gram Positive Bacteria ◽

Medicinal Value ◽

Leaf Essential Oil ◽

Plant Families ◽

Total Oil

Background: The Lamiaceae (Labiatae) is one of the most diverse and widespread plant families’ in terms of ethno medicine and its medicinal value is based on the volatile oils concentration. This family is important for flavour, fragrance and medicinal properties. Manyplants belonging to this family have indigenous value. Method: The essential oil of Plectranthus gerardianusBenth. (Lamiaceae), was analysed by GC and GC-MS analysis, while the major component was isolated and conformed by NMR spectroscopy. Result: The oil was found to be rich in oxygenated monoterpenes, which contribute around 62% of the total oil. The major components identified were fenchone (22.90%) and carvenone oxide (16.75%), besides other mono and sesquiterpenoids. The in-vitro antimicrobial activity of essential oil was tested against three gram negative bacteria viz. Pasteurellamultocida, Escherichia coli, and Salmonella enterica, two gram positive bacteria viz. Staphylococcus aureus and Bacillus subtilis and two fungi viz. Candida albicans and Aspergillusflavus. The antimicrobial activity of the oil was also compared to the antimicrobial activity of leaf essential oil of another Himalayan plant viz. Nepetacoerulescens. Conclusion: The oil showed in-vitro antimicrobial activity against all the microbial strains and can lessen the ever-growing demand of potentially hazardous antibiotics for treatment.

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Ginkgolic acid induces apoptosis and autophagy of endometrial carcinoma cells via inhibiting PI3K/Akt/mTOR pathway in vivo and in vitro

Human & Experimental Toxicology ◽

10.1177/09603271211023789 ◽

2021 ◽

pp. 096032712110237

Author(s):

L Zhou ◽

S Li ◽

J Sun

Keyword(s):

Endometrial Cancer ◽

B Cells ◽

Western Blot ◽

Signal Pathway ◽

Mtor Pathway ◽

Related Protein ◽

Western Blot Assay ◽

Ginkgolic Acid

Endometrial cancer (EC) is the fourth most common malignancy in women in developed countries. The prognosis of EC is extremely poor, and it is an important factor that contributes to the death of patients. Therefore, studying EC pathogenesis and therapeutic targets, and exploring effective drugs are the primary tasks to improve the prognosis of EC. In the present study, we aimed to explore the function of ginkgolic acid (GA) in EC cell apoptosis and autophagy through PI3K/Akt/mTOR signal pathway in vitro and in vivo. Firstly, MTT assay and clone formation assay were employed to analyze the Ishikawa and HEC-1-B cell viabilities and proliferation after treatment with GA. The results showed that GA inhibited endometrial cancer cell survival. Flow cytometry assay and western blot assay were applied to examine the apoptosis and apoptosis related protein Bcl-2, Bax, Cleaved caspase-3 expression levels of Ishikawa and HEC-1-B cells after treatment with GA. Next, we applied western blot assay to analyze the autophagy associated proteins LC3I, LC3II, p62 and Beclin-1 in GA treated Ishikawa and HEC-1-B cells. We found that GA promoted apoptosis and induced autophagy of endometrial cancer cells. Meanwhile, western blot assay was also used to determine the expression levels of the PI3K/Akt/mTOR signal pathway related protein and the results revealed that GA inhibited the activity of PI3K/Akt/mTOR pathway. Finally, we found that GA inhibited tumor growth in vivo through immunohistochemistry assay. In conclusion, GA induces apoptosis and autophagy of EC cells via inhibiting PI3K/Akt/mTOR pathway in vivo and vitro.

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Activity, expression and function of a second Drosophila protein kinase A catalytic subunit gene.

Genetics ◽

10.1093/genetics/141.4.1507 ◽

1995 ◽

Vol 141 (4) ◽

pp. 1507-1520 ◽

Cited By ~ 5

Author(s):

A Meléndez ◽

W Li ◽

D Kalderon

Keyword(s):

Protein Kinase ◽

Protein Kinase A ◽

Essential Gene ◽

Sequence Similarity ◽

Catalytic Subunit ◽

Subunit Gene ◽

Drosophila Protein ◽

Pka Catalytic Subunit ◽

Kinase A

Abstract The DC2 gene was isolated previously on the basis of sequence similarity to DC0, the major Drosophila protein kinase A (PKA) catalytic subunit gene. We show here that the 67-kD Drosophila DC2 protein behaves as a PKA catalytic subunit in vitro. DC2 is transcribed in mesodermal anlagen of early embryos. This expression depends on dorsal but on neither twist nor snail activity. DC2 transcriptional fusions mimic this embryonic expression and are also expressed in subsets of cells in the optic lamina, wing disc and leg discs of third instar larvae. A saturation screen of a small deficiency interval containing DC2 for recessive lethal mutations yielded no DC2 alleles. We therefore isolated new deficiencies to generate deficiency trans-heterozygotes that lacked DC2 activity. These animals were viable and fertile. The absence of DC2 did not affect the viability or phenotype of imaginal disc cells lacking DC0 activity or embryonic hatching of animals with reduced DC0 activity. Furthermore, transgenes expressing DC2 from a DC0 promoter did not efficiently rescue a variety of DC0 mutant phenotypes. These observations indicate that DC2 is not an essential gene and is unlikely to be functionally redundant with DC0, which has multiple unique functions during development.

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