02357nas a2200265   4500008004100000022001400041245015900055210006900214260009200283300001200375490000700387520131600394653000901710653002501719653003401744653002701778100002201805700002301827700002001850700002101870700002001891700002201911700002801933856013001961       2015                        eng d  a0968-768800aDifferential dynamics of the serotonin(1A) receptor in membrane bilayers of varying cholesterol content revealed by all atom molecular dynamics simulation0 aDifferential dynamics of the serotonin1A receptor in membrane bi  a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcMAY  a127-1370 v323 a<p>The serotonin(1A) receptor belongs to the superfamily of G protein-coupled receptors (GPCRs) and is a potential drug target in neuropsychiatric disorders. The receptor has been shown to require membrane cholesterol for its organization, dynamics and function. Although recent work suggests a close interaction of cholesterol with the receptor, the structural integrity of the serotonin(1A) receptor in the presence of cholesterol has not been explored. In this work, we have carried out all atom molecular dynamics simulations, totaling to 3s, to analyze the effect of cholesterol on the structure and dynamics of the serotonin(1A) receptor. Our results show that the presence of physiologically relevant concentration of membrane cholesterol alters conformational dynamics of the serotonin(1A) receptor and, on an average lowers conformational fluctuations. Our results show that, in general, transmembrane helix VII is most affected by the absence of membrane cholesterol. These results are in overall agreement with experimental data showing enhancement of GPCR stability in the presence of membrane cholesterol. Our results constitute a molecular level understanding of GPCR-cholesterol interaction, and represent an important step in our overall understanding of GPCR function in health and disease.</p>10aGPCR10aMembrane cholesterol10amolecular dynamics simulation10aserotonin(1A) receptor1 aPatra, Swarna, M.1 aChakraborty, Sudip1 aShahane, Ganesh1 aPrasanna, Xavier1 aSengupta, Durba1 aMaiti, Prabal, K.1 aChattopadhyay, Amitabha  uhttps://library.ncl.res.in/content/differential-dynamics-serotonin1a-receptor-membrane-bilayers-varying-cholesterol-content-002481nas a2200241   4500008004100000022001400041245016600055210006900221260000900290300001100299490000800310520158300318100002501901700001701926700001501943700002401958700002501982700002302007700002202030700002202052700003402074856013102108       2022                        eng d  a0021-960600aThermodynamics and its correlation with dynamics in a mean-field model and pinned systems: a comparative study using two different methods of entropy calculation0 aThermodynamics and its correlation with dynamics in a meanfield   cJAN   a0145030 v1563 aA recent study introduced a novel mean-field model system where each particle over and above the interaction with its regular neighbors interacts with k extra pseudo-neighbors. Here, we present an extensive study of thermodynamics and its correlation with the dynamics of this system. We surprisingly find that the well-known thermodynamic integration (TI) method of calculating the entropy provides unphysical results. It predicts vanishing of the configurational entropy at temperatures close to the onset temperature of the system and negative values of the configurational entropy at lower temperatures. Interestingly, well below the temperature at which the configurational entropy vanishes, both the collective and the single-particle dynamics of the system show complete relaxation. Negative values of the configurational entropy are unphysical, and complete relaxation when the configurational entropy is zero violates the prediction of the random first-order transition theory (RFOT). However, the entropy calculated using the two-phase thermodynamics (2PT) method remains positive at all temperatures for which we can equilibrate the system, and its values are consistent with RFOT predictions. We find that with an increase in k, the difference in the entropy computed using the two methods increases. A similar effect is also observed for a system where a randomly selected fraction of the particles are pinned in their positions in the equilibrated liquid. We show that the difference in entropy calculated via the 2PT and TI methods increases with pinning density.1 aNandi, Ujjwal, Kumar1 aPatel, Palak1 aMoid, Mohd1 aNandi, Manoj, Kumar1 aSengupta, Shiladitya1 aKarmakar, Smarajit1 aMaiti, Prabal, K.1 aDasgupta, Chandan1 aBhattacharyya, Sarika, Maitra  uhttps://library.ncl.res.in/content/thermodynamics-and-its-correlation-dynamics-mean-field-model-and-pinned-systems-comparative