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Silk is a natural protein fiber that features unique properties such as excellent mechanical properties, biocompatibility, and non-linear optical properties. These appealing physical properties originate from the silk structure, and therefore, the structural analysis of silk is of great importance for revealing the mystery of these impressive properties and developing novel silk-based biomaterials as well. Here, solid-state NMR spectroscopy was used to elucidate the secondary structure of silk proteins in N. clavipes spider dragline silk and B. mori silkworm silk. It is found that the Gly-Gly-X (X=Leu, Tyr, Gln) motif in spider dragline silk is not in a β-sheet or α-helix structure and is very likely to be present in a disordered structure with evidence for 31-helix confirmation. In addition, the conformations of the Ala, Ser, and Tyr residues in silk fibroin of B. mori were investigated and it indicates that the Ala, Ser, and Tyr residues are all present in disordered structures in silk I (before spinning), while show different conformations in silk II (after spinning). Specifically, in silk II, the Ala and Tyr residues are present in both disordered structures and β-sheet structures, and the Ser residues are present primarily in β-sheet structures.
Nuclear magnetic resonance imaging (MRI) is a technique to create a three-dimensional image of a fetus. Doctors often use MRIs to image a fetuses after an ultrasound has detected an, or has been inconclusive about an, abnormality. In 1983 researchers in Scotland first used MRI to visualize a fetus. MRIs showed a greater level of fetal detail than ultrasound images, and researchers recognized the relevance of this technique as a means to gather information about fetal development and growth. Researchers later used the technology to take measurements of the uterus, placenta, amniotic fluid, and fetus during the first trimester of pregnancy. MRI provided doctors with a non-invasive method to diagnose and treat fetal abnormalities and maternal conditions such as pre-eclampsia.
TRPM8 is the primary cold sensor in humans and is activated by ligands that feel cool such as menthol and icilin. It is implicated to be involved in a variety of cancers, nociception, obesity, addiction, and thermosensitivity. There are thought to be conserved regions of structural and functional importance to the channel which can be identified by looking at the evolution of TRPM8 over time. Along with this, looking at different isoforms of TRPM8 which are structurally very different but functionally similar can help isolate regions of functional interest as well. Between TRP channels, the transmembrane domain is well conserved and thought to be important for sensory physiology. To learn about these aspects of TRPM8, three evolutionary constructs, the last common primate, the last common mammalian, and the last common vertebrate ancestor TRPM8 were cloned and subjected to preliminary studies. In addition to the initial ancestral TRPM8 studies, fundamental studies were initiated in method development to evaluate the use of biological signaling sequences to attempt to force non-trafficking membrane protein isoforms and biophysical constructs to the plasma membrane. To increase readout for these and other studies, a cellular based fluorescence assay was initiated. Eventual completion of these efforts will lead to better understanding of the mechanism that underlie TRPM8 function and provide enhanced general methods for ion channel studies.
Beyond TRPM8 studies, an experiment was designed to probe mechanistic features of TRPV1 ligand activation. TRPV1 is also a thermosensitive channel in the TRP family, sensing heat and vanilloid ligands like capsaicin, commonly found in chili peppers. This channel is also involved in many proinflammatory interactions and associated with cancers, nociception, and addiction. Better understanding binding interactions can lead to attempts to create therapeutics.