The incorporation of unsaturated acyl chains into phospholipids during de novo synthesis is primarily mediated by the 1-acyl-sn-glycerol-3-phosphate acyltransferase reaction. In Saccharomyces cerevisiae, Slc1 has been shown to mediate this reaction, but distinct activity remains after its removal from the genome. To identify the enzyme that mediates the remaining activity, we performed synthetic genetic array analysis using a slc1⌬ strain. One of the genes identified by the screen, LPT1, was found to encode for an acyltransferase that uses a variety of lysophospholipid species, including 1-acyl-sn-glycerol-3-phosphate. Deletion of LPT1 had a minimal effect on 1-acyl-sn-glycerol-3-phosphate acyltransferase activity, but overexpression increased activity 7-fold. Deletion of LPT1 abrogated the esterification of other lysophospholipids, and overexpression increased lysophosphatidylcholine acyltransferase activity 7-fold. The majority of this activity co-purified with microsomes. To test the putative role for this enzyme in selectively incorporating unsaturated acyl chains into phospholipids in vitro, substrate concentration series experiments were performed with the four acyl-CoA species commonly found in yeast. Although the saturated palmitoyl-CoA and stearoyl-CoA showed a lower apparent K m , the monounsaturated palmitoleoyl-CoA and oleoyl-CoA showed a higher apparent V max . Arachidonyl-CoA, although not abundant in yeast, also had a high apparent V max . Pulse-labeling of lpt1⌬ strains showed a 30% reduction in [ 3 H]oleate incorporation into phosphatidylcholine only. Therefore, Lpt1p, a member of the membranebound o-acyltransferase gene family, seems to work in conjunction with Slc1 to mediate the incorporation of unsaturated acyl chains into the sn-2 position of phospholipids.

This study extended motor imagery theories by establishing specificity and verification of expected brain activation patterns during imagery. Eighteen female participants screened with the Movement Imagery Questionnaire-3 (MIQ-3) as having good imagery abilities were scanned to determine the neural networks active during an arm rotation task. Four experimental conditions (i.e., KINESTHETIC, INTERNAL Perspective, EXTERNAL Perspective, and REST) were randomly presented (counterbalanced for condition) during three brain scans. Behaviorally, moderate interscale correlations were found between the MIQ-3 and Vividness of Movement Imagery Questionnaire-2, indicating relatedness between the questionnaires. Partially confirming our hypotheses, common and distinct brain activity provides initial biological validation for imagery abilities delineated in the MIQ-3: kinesthetic imagery activated motor-related areas, internal visual imagery activated inferior parietal lobule, and external visual imagery activated temporal, but no occipital areas. Lastly, inconsistent neuroanatomical intraindividual differences per condition were found. These findings relative to recent biological evidence of imagery abilities are highlighted.

The effect of pressure on the infrared spectra of H2O and D2O ice VII has been studied at room temperature and pressures between 2 and 15 GPa with a Fourier transform infrared spectrometer and a diamond anvil high‐pressure cell. Two librational modes (νREu2 and νREu3), one bending mode ν2A2u1), and various overtone bands are well resolved. The stretching modes, ν1 and ν3, are poorly resolved due to overlap with diamond window absorption. Although νREu3 shows a very strong shift to higher frequency with pressure, ν1 and ν3 shift to lower frequencies, and all other lines vary only slightly with pressure. Differences between the spectra of H2O and D2O are discussed.

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