O- glycosylation to N-thioglycolyl-D-galactosamine peracetate

Inhibition of mucin-type O-glycosylation through metabolic processing and incorporation of N-thioglycolyl-D-galactosamine peracetate (Ac₅GalNTGc).

Mucin-type O-glycans form one of the most abundant and complex post-translational modification (PTM) on cell surface proteins that govern adhesion, migration, and trafficking of hematopoietic cells. Development of targeted approaches to probe functions of O-glycans is at an early stage. Amongst several approaches, small molecules with unique chemical functional groups that could modulate glycan biosynthesis form a critical tool. Herein, we show that metabolism of peracetyl N-acyl-D-galactosamine derivatives carrying N-thioglycolyl- (Ac₅GalNTGc, 1) moiety – but not N-glycolyl- (Ac₅GalNGc, 2) and N-acetyl- (Ac₄GalNAc, 3) – through the N-acetyl-D-galactosamine (GalNAc) salvage pathway induced abrogation of MAL-II and PNA epitopes in Jurkat cells. Mass spectrometry of permethylated O-glycans from Jurkat cells confirmed presence of significant amounts of elaborated O-glycans (sialyl-T and disialyl-T) which were inhibited upon treatment with 1.O-glycosylation of CD43, a cell surface antigen rich in O-glycans, was drastically reduced by 1 in a thiol-dependent manner. By contrast, only mild effects were observed for CD45 glycoforms. Direct metabolic incorporation of 1 was confirmed by thiol-selective Michael addition reaction of immunoprecipitated CD43-myc/FLAG. Mechanistically, CD43 glycoforms were unperturbed by peracetylated N-(3-acetylthiopropanoyl)- (4), N-(4-acetylthiobutanoyl)- (5), and N-methylthioacetyl- (6) galactosamine derivatives, N-thioglycolyl-D-glucosamine (7, C-4 epimer of 1), and α-O-benzyl 2-acetamido-2-deoxy-D-galactopyranoside (8), confirming the critical requirement of both free sulfhydryl and galactosamine moieties for inhibition of mucin-type O-glycans. Similar, yet differential, effects of 1 were observed for CD43 glycoforms in multiple hematopoietic cells. Development of small molecules that could alter glycan patterns in an antigen-selective and cell-type selective manner might provide avenues for understanding biological functions of glycans.

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PROTECTION AGAINST VISCERAL LEISHMANIASIS

Vaccination with Leishmania Hemoglobin Receptor–Encoding DNA Protects Against Visceral Leishmaniasis :-
Leishmaniasis is a severe infectious disease. Drugs used for leishmaniasis are very toxic, and no vaccine is available. We found that the hemoglobin receptor (HbR) of Leishmania was conserved across various strains of Leishmania, and anti-HbR antibody could be detected in kala-azar patients’ sera. Our results showed that immunization with HbR-DNA induces complete protection against virulent Leishmania donovani infection in both BALB/c mice and hamsters. Moreover, HbR-DNA immunization stimulated the production of protective cytokines like interferon-γ (IFN-γ), interleukin-12 (IL-12), and tumor necrosis factor–α (TNF-α) with concomitant down-regulation of disease-promoting cytokines like IL-10 and IL-4. HbR-DNA vaccination also induced a protective response by generating multifunctional CD4+ and CD8+ T cells. All HbR-DNA–vaccinated hamsters showed sterile protection and survived during an experimental period of 8 months. These findings demonstrate the potential of HbR as a vaccine candidate against visceral leishmaniasis.

Protein to stop cancer metastasis

Protein inhibit cancer metastasis

Mien-Chie Hung, Ph.D., is a professor and chair of MD Anderson's Department of Molecular and Cellular Oncology.

By sticking a chemical group to it at a specific site, a protein arrests an enzyme that may worsen and spread cancer, an international research team led by researchers at The University of Texas MD Anderson Cancer Center reports in the recent issue of Nature Cell Biology 
In addition to highlighting a novel anti-cancer pathway, the team observed that the same deactivation of the enzyme called EZH2 is necessary for the formation of bone-forming cells from the stem cells that make them and other tissues. 

"EZH2 is overexpressed in aggressive solid tumors and tied to cancer progression and metastasis," said the paper's senior author, Mien-Chie Hung, Ph.D., professor and chair of MD Anderson's Department of Molecular and Cellular Oncology. "We have observed that another protein, CDK1, deactivates EZH2". 

The team's basic research findings provide a rationale for developing an EZH2 inhibitor or a drug that mimics the protein that deactivates it as new cancer drugs. "You have to understand the molecular details of cancer formation and progression to develop new therapies that improve therapy and prevention," Hung said. 

In a series of experiments, the team demonstrated how CDK1 interferes with EZH2, reducing cell migration and invasion in breast cancer cell lines. 

EZH2 silences gene expression by attaching a methyl group, which consists of one carbon and three hydrogen atoms, to a histone protein that is intertwined with DNA and other proteins to compose chromosomes. Genes suppressed by this methylation include tumor suppressors that would otherwise prevent cancer growth and spread. 

The team showed that CDK1 short-circuits EZH2-mediated methylation by attaching a different chemical group consisting of one phosphate and three oxygen atoms to EZH2, a process called phosphorylation. And that phosphorylation has to occur at a specific amino acid on EZH2 to have this effect. 

It's a matter of phosphorylation trumping methylation, Hung said. The phosphorylated version of EZH2 cannot methylate the target histone protein, so repressed genes are awakened. 

Cancer cells with EZH2 that had a mutant version of the location where the phosphate group connects, preventing phosphorylation, had double the cell migration and invasion of cancer cells with the regular, unmutated version of EZH2. 


Same process vital to bone formation 
EZH2 plays an important normal role in a variety of biological processes. "EZH2 is crucial to embryonic development because it turns genes off and on to guide the differentiation of embryonic stem cells into tissues and organs," Hung said. Embryonic stem cells can turn into any type of cell. 

In a separate set of experiments, the scientists demonstrated that phosphorylation of EZH2 is necessary to the production of bone cells (osteoblasts). 

Mesenchymal stem cells can differentiate into bone, cartilage or fat cells. The team showed only those cells with EZH2 phosphorylated by CDK1 differentiated into bone cells. Genes crucial to bone formation were silenced by methlyation but awakened when CDK1 altered EZH2. 

A genomewide screen to identify genes targeted by EZH2 in mesenchymal stem cells was conducted before and after the cells differentiated into bone cells. Before, more than 4,000 genes were found to bind to EZH2. After differentiation to bone cells, 30 or fewer genes bound to the protein. 

"This and other recently reported studies open up drug development possibilities by either inhibiting the methyltransferase activity of EZH2 or regulating phosphorylation to indirectly regulate EZH2's activity," Hung said. 

"This study also suggests a possible way to induce mesenchymal stem cell differentiation into bone cells, which may have long-term implications for regenerative medicine for bone disease," Hung said. 

CYTOSKELETON & ITS surface Receptor :/

Cell's cytoskeleton and its surface receptors

CD36 trajectories in a primary human macrophage from a 10 Hz/10 s single-molecule movie. Scale bar, 2 µm. Red, linear trajectories; cyan, isotropic trajectories. The linear motion of receptors, which depends on the actin meshwork and on microtubules, enhances receptor clustering in the absence of ligand, priming the macrophages to respond when exposed to ligand.

New findings from scientists at Harvard Medical School in Boston and the Hospital for Sick Children in Toronto may shed light on the mechanisms that regulate the organization of receptors on the cell surface, a critical aspect of cell signaling not well understood at this time. 

The group reports on their use of the macrophage protein CD36, a clustering-responsive class B scavenger receptor, as a model for studying the processes governing receptor clustering and organization. The protein is involved in many cellular and physiological functions that range from lipid metabolism to immunity, but it is unknown how the CD36 protein is organized in the cell (as monomers or as oligomers) and how that organization leads to its biological functions. 

The scientists employed a combination of powerful tools: quantitative live-cell single-molecule imaging and biochemical/pharmacological approaches to study the dynamics, oligomerization and signaling of CD36 in primary human macrophages. 

The group reports that movement of CD36 in the macrophage plasma membrane is regulated by the sub-membranous actin meshwork and by microtubules, demonstrating that these cytoskeletal components might play a critical role in receptor function, in general. 

In terms of the impact of this research, lead researcher Khuloud Jaqaman says: "In the long run, establishing the relationship between receptor organization and cell signaling might aid in the development of drugs since receptors on the cell surface are the most accessible to pharmacological manipulation". 

BELIEVE IT!!

1. EATING A BANANA CAN HELP TO CHEER YOU UP!!

Bananas are the only fruits to contain the amino acid... tryptophan and vitamin B6, which together help the body to manufacture serotonin- the natural chemical to help combat depression.

2. The world's largest virus and a unique genome 93% of its genome doesn't matches with any other organism DNA... a hint to fourth domain of life

3. seahorse is the only fish to have neck.

4. Slug evolved from snail.....exposing baby snails to platinum turn them to SLUG.

5.The longest word in english is the chemical name of the protein TITIN (189,819 letters).

6.Time is slightly faster 12 inches above the ground...this means your feet is slightly younger then your head

7. A teaspoon of honey represent... the lifetime work of 12 bees.

Memories never DIE!!

THE INSANE 

LOVE * LOVE * LOVE ^-^

 HAUZ KHAS VILLAGE trip....OMG!!
Guide- SACHIN BHATT... a long walk with frequent stoppages and a question in each face- sachin more how long we need to walk n like every time, the same answer ...guys just 2 minute... and trust me that awaited 2 minute came but after 45 minute... THE CRAZY NEST CARRIER!! 

 FIRST hang out ... at New friends colony(NFC) after recovery from JAUNDICE!! :)
THANK YOU -------sachin :D

Bewade sab k sab!! :* <3

:* :* :* :*:*

GRADUATION!!  :D :D

A
USELESS DISCUSSION!! :) :)

AAHHH!! Those long wait of yours just to gather some guts and finnaly few words with her under the EARTH ...oh!! I mean in the subway(NEHRU PLACE, NEW DELHI) :D :D ...but trust me.... still, I cherish those moments...  :D :D

TULSI (Ocimum tenuiflorum)

                                Tulsi gives oxygen for 20 hours and ozone for four hours a day along with the formation of nascent oxygen which absorbs harmful gases like carbon monoxide, carbon dioxide and sulphur dioxide from the environment," said Shyamkant Padoley, an eminent botanist.

Tulasi is a sacred plant highly revered in Hindu mythology.   So much to the extent that it is an integral part of Indian household and is worshiped with devotion and faith  that it bestows the household  with good luck and keeps the evil away.Tulasi is composed of two words i.e.TULA= compare; ASI=no; means “the incomparable” so this shows the significance of tulasi as medicine. It is also called as HOLY-BASIL.

            Since TULASI releases O3 that is ozone gas which has 3- molecules of oxygen (unlike other plants which release only OXYGEN} very important to protect the environment. The ozone layer is the one which protects the earth from the radiation of sun. So, its role as radio protective agent is also being researched. That is why it is mandatory to plant TULASI in the midst of the courtyard (angan) so that it could receive maximum sunlight.

            It is lagu, ruksh with katu, tikt Rasa. It has katu vipaka and ushan veerya.  It is sattavic in nature and promotes the sattavic gunas. It is heart stimulant, blood purifier and anti inflammatory i.e.; shoth-har. It is kaphagan and seeds are diuretic. It is javaragan especially the visham-javar.the seeds are balya means give energy to the body. It is anti fungal and mouth freshener as mentioned in ayurvedic texts.

           

            Other benefits of holy basil are –it has antifungal and anti viral properties. Paste of tulasi leaves is very good for skin and can be used for blemishes. The juice of tulasi leaves (1-2 tolas) with honey relieves pain and flushes out the stone

As per the research conducted by DR, RALF MILLER former director of research for Canadian dept. of health and welfare tulasi is IMMUNOMODULATOR means that it balances and improves the immune system. It is ANTIOXIDANT thus it prevents and protects the body from free radicals. It is ADAPTOGENIC means it helps the body adapt more efficiently to the stress. It is ANTI-ALLERGEN so can be used in allergic cough and cold. Tulasi tea is rich source of phytochemicals.

Modern scientific research shows that tulasi reduces stress, enhances stamina, relieves inflammation, lowers cholesterol, eliminates toxins, protects from radiation,  lowers fevers, improves digestion provides rich supply of antioxidants and other nutrients, especially effective in supporting heart, blood-vessels, lungs and liver. It lowers blood sugar and regulates blood pressure. And all these properties of tulasi have been mentioned in old ayurvedic texts. Tulasi is known to purify and depolloute the atmosphere and also acts as mosquito repellent and other insects due to its strong odor. So it should be planted near windows and the entrance door. The fragrance of tulasi has distressing effect and good for lungs too so it is good for asthmatic patients. Phant of 10-12 leaves of tulasi with half crushed kali marich cures malaria and other periodic fevers. Since, its leaves are nervine tonic so to improve memory 7-8 leaves of tulasi, 4 kali mrich, 2 almonds can be taken with honey.persistant thirst can be done away by taking sherbet of tulasi leaves with sugar and lemon. Regular use of tulasi helps in rapid increase of RBcells .rama tulsi leaves can be taken with cow’s milk and sugar to relieve fatigue. Tulasi is said to be ELIXIR OF LIFE. As it promotes longevity.