A Taste for Learning

Understanding mechanisms of learning and memory storage in thehuman brain will contribute to designing strategies for optimizingthis functionality in both biological and electronic neuralnetworks. Studies of memory-deficient patients have localizedsome of the critical brain areas for memory storage and establishedthat different types of information can be stored in anatomicallyseparate locations. Studies of cellular and biochemical eventsduring associative learning in several molluscan neural networkshave produced detailed hypotheses about the causative eventsleading to changes in synaptic function during learning. Useof recently developed preparations of mammalian CNS should allowdirect tests of the generality of the molluscan mechanisms forsynaptic plasticity during learning in the mammalian brain.     

A Keystone for ncRNA

A report on the Keystone symposium 'Non-coding RNAs' held at Snowbird, Utah, USA, 31 March to 5 April 2012.     

A microassay for ATPase

A newly developed microtechnique for quantitating activity of myosin ATPase (EC 3.6.1.32) is more sensitive and less time-consuming than existing spectrophotometric methods. Measurement of ATPase activity using the new method can be accomplished in a final volume of 0.25 ml, allowing the assay to be conducted in individual wells of 96-well microplates commonly used for the enzyme-linked immunosorbent assay (ELISA). The microassay is performed by adding purified myosin to microplate wells followed by addition of ATP to initiate the enzymatic reaction. The reaction is subsequently terminated by addition of an acidic solution containing malachite green and ammonium molybdate. The level of inorganic phosphate produced by enzymatic hydrolysis of ATP is measured by scanning the microplates using a microELISA plate reader. An entire 96-well microplate can be scanned in less than 2 min, and data from the microassay can be transferred directly to a microprocessor for statistical analysis. The microassay is capable of detecting between 0.2 and 3 nmol of inorganic phosphate in a reaction volume of 50 microliter, and the ATPase activity of as little as 10 ng of rat cardiac myosin can be measured. The increased sensitivity compared with that of other spectrophotometric assays and ease of performing the microassay enable a detailed analysis of the enzymatic properties of cardiac myosin to be conducted on large numbers of small tissue specimens. Several kinetic properties of rat cardiac myosin were determined using this technique.