Featured Photos

Jonathan image1
Raw single molecule imaging data of the bacterial transporter LeuT as the speckles on the black background. The trace shows the FRET measurements from a single molecule. The molecule shows the crystal structure and a computational simulation of the transporter opening to release substrate to the inside, which is was is being gated above by addition of substrate for the enhanced frequency of FRET. see Jonathan Javitch, Ph.D.
Christoph image1
Three-dimensional reconstruction of the neuronal projections from the prefrontal cortex to the striatum in the mouse. The cortico-striatal system is affected in several psychiatric disorders and changes in the connectivity of these projections are postulated. Genetic mouse models can be used to study the molecules that are involved in organizing the cortico-striatal projections. Red: striatal projections fields, Pink: injection side in the prefrontal cortex, Blue: left striatum, Green: right striatum, Brown: cortex. see Christoph Kellendonk, Ph.D.
Inhibitory neurotransmission is mediated primarily by γ-aminobutyric acid (GABA). Metabotropic GABAB receptor is a G-protein coupled receptor central to mammalian brain function, as it regulates Ca2+- and K+-channel activity and inhibits adenylyl cyclase. Malfunction of GABAB receptor has been implicated in the development of several diseases including spasticity, epilepsy and pain. GABAB receptor functions as a heterodimeric assembly of GBR1 and GBR2 subunits, in which GBR1 is responsible for ligand-binding and GBR2 is responsible for G-protein coupling. Here we present the crystal structure of GBR2 ectodomain, which reveals a polar heterodimeric interface. Our structural and functional data indicate that GBR2 ectodomain adopts a constitutively open conformation, suggesting a structural asymmetry in the active state of GABAB receptor that is entirely unique to the GABAergic system. see Qiang Fan, Ph.D.
Voltage-dependent fluorescence signals from KCNQ1 C214A/C331A G219C suggest 1:1 coupling between voltage sensor movement and channel activation. (A) Schematic of the VCF technique. PD, photodiode photodetector. (B) Topology of the KCNQ1 and KCNE1 proteins in the cell membrane. Residues in the S3-S4 linker that were sequentially mutated to Cys are shown, with the residue G219 highlighted in green. (C and D) Representative current (C) and fluorescence (D) from Alexa488-labeled KCNQ1 C214A/C331A G219C (psKCNQ1). Cells are held at −80 mV and stepped to potentials between −120 mV and +60 mV for 2 s followed by a step to −40 mV (current) or −80 mV (fluorescence). see Robert Kass, Ph.D.
Intracellular Ca2+ release activity (Ca2+ sparks) can be imaged in a single Purkinje cell (inset) of the heart using a line scan confocal microscope. Above we have compared the individual Ca2+ sparks of Purkinje cells from control noninfarcted hearts (NZPCs) and those from Purkinje cells that survive in the arrhythmogenic infarcted ventricle (IZPCs). Note the increased frequency of sparks in IZPCs. In addition there are larger Ca2+ events called Ca2+ waves (above) and Ca wavelets (below). These events are spontaneous and can lead to arrhythmias in these single cells and whole heart. see Penelope Boyden, Ph.D.
Calcium imaging in an axonal growth cone, top column: Fura-2 calcium-bound, bottom column: Fura-2 calcium-free, far right row before, middle row during and left row following activation of NMDA glutamate receptors, pseudocolor indicates calcium concentration. see David Sulzer, Ph.D.