How to Study Protein-Ligand Interaction through Molecular Docking [online video]

Attendees will be introduced to molecular docking technology. Open source computational tools that can be used to study the interactions of protein-ligand complexes will be highlighted. A case study handout is also available for download

Growth performance of litopenaeus vannamei in biofloc treatments grown with different carbon sources

Experiments were conducted with three biofloc treatments and one control in triplicate in 1000 ltr capacity indoor tanks and water level filled up to 600 ltr. Enhanced shrimp growth was noticed in biofloc treatment tanks and a significant difference in the final average body weight of (15.92±0.07g) was found in the wheat flour treated shrimps than those of control group shrimp. The Feed Conversion Ratio differs significantly (P<0.05) between biofloc treatment group and control groups. Lowest FCR (0.5±0.07) was recorded in wheat flour as carbohydrate source biofloc treatment during the experiment. Highest Specific Growth Rate (4.59) was observed in the wheat flour treatment groups than that of other treatments and control groups. Wheat flour utilization as carbohydrate source to biofloc development for rearing of L. vannamei was proved to be the best option among all treatments. All the carbohydrate sources (wheat flour, tapioca flour and molasses) utilized for biofloc treatments indicated highest growth than control treatment

Properties and distribution of paired candidate stony meteorites at Meridiani Planum, Mars

The Mars Exploration Rover Opportunity investigated four rocks, informally dubbed Barberton, Santa Catarina, Santorini, and Kasos, that are possible stony meteorites. Their chemical and mineralogical composition is similar to the howardite, eucrite, and diogenite group but with additional metal, similar to mesosiderite silicate clasts. Because of their virtually identical composition and because they appear to represent a relatively rare group of meteorites, they are probably paired. The four rocks were investigated serendipitously several kilometers apart, suggesting that Opportunity is driving across a larger population of similar rock fragments, maybe a meteorite strewn field. Small amounts of ferric Fe are a result of weathering. We did not observe evidence for fusion crusts. Four iron meteorites were found across the same area. Although mesosiderites are stony irons, a genetic link to these irons is unlikely. The stony meteorites probably fell later than the irons. The current atmosphere is sufficiently dense to land such meteorites at shallow entry angles, and it would disperse fragments over several kilometers upon atmospheric breakup. Alternatively, dispersion by spallation from an impacting meteoroid may have occurred. Santa Catarina and a large accumulation of similar rocks were found at the rim of Victoria crater. It is possible that they are associated with the impactor that created Victoria crater, but our limited knowledge about their distribution cannot exclude mere coincidence

RhoD Inhibits RhoC-ROCK-Dependent Cell Contraction via PAK6.

RhoA-mediated regulation of myosin-II activity in the actin cortex controls the ability of cells to contract and bleb during a variety of cellular processes, including cell migration and division. Cell contraction and blebbing also frequently occur as part of the cytopathic effect seen during many different viral infections. We now demonstrate that the vaccinia virus protein F11, which localizes to the plasma membrane, is required for ROCK-mediated cell contraction from 2 hr post infection. Curiously, F11-induced cell contraction is dependent on RhoC and not RhoA signaling to ROCK. Moreover, RhoC-driven cell contraction depends on the upstream inhibition of RhoD signaling by F11. This inhibition prevents RhoD from regulating its downstream effector Pak6, alleviating the suppression of RhoC by the kinase. Our observations with vaccinia have now demonstrated that RhoD recruits Pak6 to the plasma membrane to antagonize RhoC signaling during cell contraction and blebbing

Meteorites on Mars observed with the Mars Exploration Rovers

Reduced weathering rates due to the lack of liquid water and significantly greater typical surface ages should result in a higher density of meteorites on the surface of Mars compared to Earth. Several meteorites were identified among the rocks investigated during Opportunity&rsquo;s traverse across the sandy Meridiani plains. Heat Shield Rock is a IAB iron meteorite and has been officially recognized as &lsquo;&lsquo;Meridiani Planum.&rsquo;&rsquo; Barberton is olivine-rich and contains metallic Fe in the form of kamacite, suggesting a meteoritic origin. It is chemically most consistent with a mesosiderite silicate clast. Santa Catarina is a brecciated rock with a chemical and mineralogical composition similar to Barberton. Barberton, Santa Catarina, and cobbles adjacent to Santa Catarina may be part of a strewn field. Spirit observed two probable iron meteorites from its Winter Haven location in the Columbia Hills in Gusev Crater. Chondrites have not been identified to date, which may be a result of their lower strengths and probability to survive impact at current atmospheric pressures. Impact craters directly associated with Heat Shield Rock, Barberton, or Santa Catarina have not been observed, but such craters could have been erased by eolian-driven erosion.Additional co-authors: DW Ming, RV Morris, PA de Souza Jr, SW Squyres, C Weitz, AS Yen, J Zipfel, T Economo

Modeling mitochondrial dysfunctions in the brain: from mice to men

The biologist Lewis Thomas once wrote: “my mitochondria comprise a very large proportion of me. I cannot do the calculation, but I suppose there is almost as much of them in sheer dry bulk as there is the rest of me”. As humans, or indeed as any mammal, bird, or insect, we contain a specific molecular makeup that is driven by vast numbers of these miniscule powerhouses residing in most of our cells (mature red blood cells notwithstanding), quietly replicating, living independent lives and containing their own DNA. Everything we do, from running a marathon to breathing, is driven by these small batteries, and yet there is evidence that these molecular energy sources were originally bacteria, possibly parasitic, incorporated into our cells through symbiosis. Dysfunctions in these organelles can lead to debilitating, and sometimes fatal, diseases of almost all the bodies’ major organs. Mitochondrial dysfunction has been implicated in a wide variety of human disorders either as a primary cause or as a secondary consequence. To better understand the role of mitochondrial dysfunction in human disease, a multitude of pharmacologically induced and genetically manipulated animal models have been developed showing to a greater or lesser extent the clinical symptoms observed in patients with known and unknown causes of the disease. This review will focus on diseases of the brain and spinal cord in which mitochondrial dysfunction has been proven or is suspected and on animal models that are currently used to study the etiology, pathogenesis and treatment of these diseases

The limits of India’s ethno-linguistic federation: understanding the demise of Sikh nationalism

From 1984 until 1993, the Indian state of Punjab witnessed a sustained insurgency by Sikh militants campaigning for a separate sovereign state. This insurgency was ultimately defeated by the overwhelming use of security force that officially resulted in the deaths of 30,000 people. By the mid-1990s, a ‘normalcy’ had returned to Punjab politics, but the underlying issues which had fuelled the demand for separatism remain unaddressed. This paper examines critically the argument that India’s ethno-linguistic federation is exceptional in accommodating ethno-nationalist movements. By drawing on the Punjab case study, it argues that special considerations apply to the governance of peripheral regions (security, religion). Regional elites in these states struggle to build legitimacy because such legitimacy poses a threat to India’s nation and state-building. In short, India’s ethno-linguistic federation is only partially successful in managing ethno-linguistic demands in the peripheral Indian states