Filter
Associated Lab
- 43418 (30) Apply 43418 filter
- 43427 (22) Apply 43427 filter
- 43430 (64) Apply 43430 filter
- 43438 (5) Apply 43438 filter
- 46293 (6) Apply 46293 filter
- Ahrens Lab (48) Apply Ahrens Lab filter
- Aso Lab (32) Apply Aso Lab filter
- Baker Lab (38) Apply Baker Lab filter
- Betzig Lab (106) Apply Betzig Lab filter
- Beyene Lab (8) Apply Beyene Lab filter
- Bock Lab (17) Apply Bock Lab filter
- Branson Lab (43) Apply Branson Lab filter
- Card Lab (31) Apply Card Lab filter
- Cardona Lab (63) Apply Cardona Lab filter
- Chklovskii Lab (13) Apply Chklovskii Lab filter
- Clapham Lab (11) Apply Clapham Lab filter
- Cui Lab (19) Apply Cui Lab filter
- Darshan Lab (10) Apply Darshan Lab filter
- Dennis Lab (1) Apply Dennis Lab filter
- Dickson Lab (43) Apply Dickson Lab filter
- Druckmann Lab (25) Apply Druckmann Lab filter
- Dudman Lab (44) Apply Dudman Lab filter
- Eddy/Rivas Lab (30) Apply Eddy/Rivas Lab filter
- Egnor Lab (11) Apply Egnor Lab filter
- Espinosa Medina Lab (14) Apply Espinosa Medina Lab filter
- Feliciano Lab (5) Apply Feliciano Lab filter
- Fetter Lab (41) Apply Fetter Lab filter
- Fitzgerald Lab (24) Apply Fitzgerald Lab filter
- Freeman Lab (15) Apply Freeman Lab filter
- Funke Lab (25) Apply Funke Lab filter
- Gonen Lab (91) Apply Gonen Lab filter
- Grigorieff Lab (62) Apply Grigorieff Lab filter
- Harris Lab (49) Apply Harris Lab filter
- Heberlein Lab (94) Apply Heberlein Lab filter
- Hermundstad Lab (18) Apply Hermundstad Lab filter
- Hess Lab (62) Apply Hess Lab filter
- Jayaraman Lab (41) Apply Jayaraman Lab filter
- Ji Lab (32) Apply Ji Lab filter
- Johnson Lab (6) Apply Johnson Lab filter
- Kainmueller Lab (19) Apply Kainmueller Lab filter
- Karpova Lab (13) Apply Karpova Lab filter
- Keleman Lab (13) Apply Keleman Lab filter
- Keller Lab (74) Apply Keller Lab filter
- Koay Lab (16) Apply Koay Lab filter
- Lavis Lab (117) Apply Lavis Lab filter
- Lee (Albert) Lab (31) Apply Lee (Albert) Lab filter
- Leonardo Lab (23) Apply Leonardo Lab filter
- Li Lab (24) Apply Li Lab filter
- Lippincott-Schwartz Lab (143) Apply Lippincott-Schwartz Lab filter
- Liu (Yin) Lab (5) Apply Liu (Yin) Lab filter
- Liu (Zhe) Lab (50) Apply Liu (Zhe) Lab filter
- Looger Lab (134) Apply Looger Lab filter
- Magee Lab (49) Apply Magee Lab filter
- Menon Lab (18) Apply Menon Lab filter
- Murphy Lab (13) Apply Murphy Lab filter
- O'Shea Lab (4) Apply O'Shea Lab filter
- Pachitariu Lab (33) Apply Pachitariu Lab filter
- Pastalkova Lab (18) Apply Pastalkova Lab filter
- Pavlopoulos Lab (19) Apply Pavlopoulos Lab filter
- Pedram Lab (12) Apply Pedram Lab filter
- Podgorski Lab (15) Apply Podgorski Lab filter
- Reiser Lab (41) Apply Reiser Lab filter
- Riddiford Lab (44) Apply Riddiford Lab filter
- Romani Lab (37) Apply Romani Lab filter
- Rubin Lab (131) Apply Rubin Lab filter
- Saalfeld Lab (51) Apply Saalfeld Lab filter
- Scheffer Lab (35) Apply Scheffer Lab filter
- Schreiter Lab (54) Apply Schreiter Lab filter
- Sgro Lab (20) Apply Sgro Lab filter
- Shroff Lab (12) Apply Shroff Lab filter
- Simpson Lab (23) Apply Simpson Lab filter
- Singer Lab (79) Apply Singer Lab filter
- Spruston Lab (89) Apply Spruston Lab filter
- Stern Lab (141) Apply Stern Lab filter
- Sternson Lab (53) Apply Sternson Lab filter
- Stringer Lab (18) Apply Stringer Lab filter
- Svoboda Lab (130) Apply Svoboda Lab filter
- Tebo Lab (26) Apply Tebo Lab filter
- Tervo Lab (8) Apply Tervo Lab filter
- Tillberg Lab (14) Apply Tillberg Lab filter
- Tjian Lab (64) Apply Tjian Lab filter
- Truman Lab (87) Apply Truman Lab filter
- Turaga Lab (43) Apply Turaga Lab filter
- Turner Lab (25) Apply Turner Lab filter
- Vale Lab (3) Apply Vale Lab filter
- Wang (Shaohe) Lab (1) Apply Wang (Shaohe) Lab filter
- Wu Lab (9) Apply Wu Lab filter
- Zlatic Lab (29) Apply Zlatic Lab filter
- Zuker Lab (25) Apply Zuker Lab filter
Associated Project Team
- COSEM (2) Apply COSEM filter
- Fly Descending Interneuron (7) Apply Fly Descending Interneuron filter
- Fly Functional Connectome (13) Apply Fly Functional Connectome filter
- Fly Olympiad (4) Apply Fly Olympiad filter
- FlyEM (55) Apply FlyEM filter
- FlyLight (33) Apply FlyLight filter
- GENIE (33) Apply GENIE filter
- Larval Olympiad (2) Apply Larval Olympiad filter
- MouseLight (14) Apply MouseLight filter
- NeuroSeq (1) Apply NeuroSeq filter
- ThalamoSeq (1) Apply ThalamoSeq filter
- Tool Translation Team (T3) (11) Apply Tool Translation Team (T3) filter
- Transcription Imaging (49) Apply Transcription Imaging filter
Publication Date
- 2023 (13) Apply 2023 filter
- 2022 (202) Apply 2022 filter
- 2021 (187) Apply 2021 filter
- 2020 (191) Apply 2020 filter
- 2019 (191) Apply 2019 filter
- 2018 (230) Apply 2018 filter
- 2017 (210) Apply 2017 filter
- 2016 (207) Apply 2016 filter
- 2015 (249) Apply 2015 filter
- 2014 (237) Apply 2014 filter
- 2013 (192) Apply 2013 filter
- 2012 (187) Apply 2012 filter
- 2011 (188) Apply 2011 filter
- 2010 (160) Apply 2010 filter
- 2009 (157) Apply 2009 filter
- 2008 (139) Apply 2008 filter
- 2007 (106) Apply 2007 filter
- 2006 (92) Apply 2006 filter
- 2005 (67) Apply 2005 filter
- 2004 (57) Apply 2004 filter
- 2003 (58) Apply 2003 filter
- 2002 (39) Apply 2002 filter
- 2001 (28) Apply 2001 filter
- 2000 (29) Apply 2000 filter
- 1999 (14) Apply 1999 filter
- 1998 (18) Apply 1998 filter
- 1997 (16) Apply 1997 filter
- 1996 (10) Apply 1996 filter
- 1995 (18) Apply 1995 filter
- 1994 (12) Apply 1994 filter
- 1993 (10) Apply 1993 filter
- 1992 (6) Apply 1992 filter
- 1991 (11) Apply 1991 filter
- 1990 (11) Apply 1990 filter
- 1989 (6) Apply 1989 filter
- 1988 (1) Apply 1988 filter
- 1987 (7) Apply 1987 filter
- 1986 (4) Apply 1986 filter
- 1985 (5) Apply 1985 filter
- 1984 (2) Apply 1984 filter
- 1983 (2) Apply 1983 filter
- 1982 (3) Apply 1982 filter
- 1981 (3) Apply 1981 filter
- 1980 (1) Apply 1980 filter
- 1979 (1) Apply 1979 filter
- 1976 (2) Apply 1976 filter
- 1973 (1) Apply 1973 filter
- 1970 (1) Apply 1970 filter
- 1967 (1) Apply 1967 filter
Type of Publication
3582 Publications
Showing 3511-3520 of 3582 results1. The voltage- and space-clamp errors associated with the use of a somatic electrode to measure current from dendritic synapses are evaluated using both equivalent-cylinder and morphologically realistic models of neuronal dendritic trees. 2. As a first step toward understanding the properties of synaptic current distortion under voltage-clamp conditions, the attenuation of step and sinusoidal voltage changes are evaluated in equivalent cylinder models. Demonstration of the frequency-dependent attenuation of voltage in the cable is then used as a framework for understanding the distortion of synaptic currents generated at sites remote from the somatic recording electrode and measured in the voltage-clamp recording configuration. 3. Increases in specific membrane resistivity (Rm) are shown to reduce steady-state voltage attenuation, while producing only minimal reduction in attenuation of transient voltage changes. Experimental manipulations that increase Rm therefore improve the accuracy of estimates of reversal potential for electrotonically remote synapses, but do not significantly reduce the attenuation of peak current. In addition, increases in Rm have the effect of slowing the kinetics of poorly clamped synaptic currents. 4. The effects of the magnitude of the synaptic conductance and its kinetics on the measured synaptic currents are also examined and discussed. The error in estimating parameters from measured synaptic currents is greatest for synapses with fast kinetics and large conductances. 5. A morphologically realistic model of a CA3 pyramidal neuron is used to demonstrate the generality of the conclusions derived from equivalent cylinder models. The realistic model is also used to fit synaptic currents generated by stimulation of mossy fiber (MF) and commissural/associational (C/A) inputs to CA3 neurons and to estimate the amount of distortion of these measured currents. 6. Anatomic data from the CA3 pyramidal neuron model are used to construct a simplified two-cylinder CA3 model. This model is used to estimate the electrotonic distances of MF synapses (which are located proximal to the soma) and perforant path (PP) synapses (which are located at the distal ends of the apical dendrites) and the distortion of synaptic current parameters measured for these synapses. 7. Results from the equivalent-cylinder models, the morphological CA3 model, and the simplified CA3 model all indicate that the amount of distortion of synaptic currents increases steeply as a function of distance from the soma. MF synapses close to the soma are likely to be subject only to small space-clamp errors, whereas MF synapses farther from the soma are likely to be substantially attenuated.(ABSTRACT TRUNCATED AT 400 WORDS)
We have constructed a series of strains to facilitate the generation and analysis of clones of genetically distinct cells in developing and adult tissues of Drosophila. Each of these strains carries an FRT element, the target for the yeast FLP recombinase, near the base of a major chromosome arm, as well as a gratuitous cell-autonomous marker. Novel markers that carry epitope tags and that are localized to either the cell nucleus or cell membrane have been generated. As a demonstration of how these strains can be used to study a particular gene, we have analyzed the developmental role of the Drosophila EGF receptor homolog. Moreover, we have shown that these strains can be utilized to identify new mutations in mosaic animals in an efficient and unbiased way, thereby providing an unprecedented opportunity to perform systematic genetic screens for mutations affecting many biological processes.
Human mitochondrial transcription factor A is a 25-kDa protein that binds immediately upstream of the two major mitochondrial promoters, thereby leading to correct and efficient initiation of transcription. Although the nature of yeast mitochondrial promoters is significantly different from that of human promoters, a potential functional homolog of the human transcriptional activator protein has been previously identified in yeast mitochondria. The importance of the yeast protein in yeast mitochondrial DNA function has been shown by inactivation of its nuclear gene (ABF2) in Saccharomyces cerevisiae cells resulting in loss of mitochondrial DNA. We report here that the nuclear gene for human mitochondrial transcription factor A can be stably expressed in yeast cells devoid of the yeast homolog protein. The human protein is imported efficiently into yeast mitochondria, is processed correctly, and rescues the loss-of-mitochondrial DNA phenotype in a yeast abf2 strain, thus functionally substituting for the yeast protein. Both human and yeast proteins affect yeast mitochondrial transcription initiation in vitro, suggesting that the two proteins may have a common role in this fundamental process.
A new and conceptually simple data structure, called a suffix array, for on-line string searches is introduced in this paper. Constructing and querying suffix arrays is reduced to a sort and search paradigm that employs novel algorithms. The main advantage of suffix arrays over suffix trees is that, in practice, they use three to five times less space. From a complexity standpoint, suffix arrays permit on-line string searches of the type, ‘‘Is W a substring of A?’’ to be answered in time O(P + log N), where P is the length of W and N is the length of A, which is competitive with (and in some cases slightly better than) suffix trees. The only drawback is that in those instances where the underlying alphabet is finite and small, suffix trees can be constructed in O(N) time in the worst case, versus O(N log N) time for suffix arrays. However, we give an augmented algorithm that, regardless of the alphabet size, constructs suffix arrays in O(N) expected time, albeit with lesser space efficiency. We believe that suffix arrays will prove to be better in practice than suffix trees for many applications.
Recent advances in probe design have led to enhanced resolution (currently as significant as 12 nm) in optical microscopes based on near-field imaging. We demonstrate that the polarization of emitted and detected light in such microscopes can be manipulated sensitively to generate contrast. We show that the contrast on certain patterns is consistent with a simple interpretation of the requisite boundary conditions, whereas in other cases a more complicated interaction between the probe and the sample is involved. Finally application of the technique to near-filed magneto-optic imaging is demonstrated.
The near-field optical interaction between a sharp probe and a sample of interest can be exploited to image, spectroscopically probe, or modify surfaces at a resolution (down to approximately 12 nm) inaccessible by traditional far-field techniques. Many of the attractive features of conventional optics are retained, including noninvasiveness, reliability, and low cost. In addition, most optical contrast mechanisms can be extended to the near-field regime, resulting in a technique of considerable versatility. This versatility is demonstrated by several examples, such as the imaging of nanometric-scale features in mammalian tissue sections and the creation of ultrasmall, magneto-optic domains having implications for highdensity data storage. Although the technique may find uses in many diverse fields, two of the most exciting possibilities are localized optical spectroscopy of semiconductors and the fluorescence imaging of living cells.
Commentary: An overview of our work in near-field optics at the time, after our invention of the adiabatically tapered fiber probe and shear force feedback (see below) led to the first practical near-field scanning optical microscope. In this work, superresolution imaging via absorption, reflectivity, fluorescence, spectroscopy, polarization, and refractive index contrast were all demonstrated. Unlike all far-field superresolution fluorescence methods that were to appear a decade later, near-field microscopy remains the only superresolution technique capable of taking advantage of the full panoply of optical contrast mechanisms.
The argos gene encodes a protein that is required for viability and that regulates the determination of cells in the Drosophila eye. A developmental analysis of argos mutant eyes indicates that the mystery cells, which are usually nonneuronal, are transformed into extra photoreceptors, and that supernumerary cone cells and pigment cells are also recruited. Clonal analysis indicates that argos acts nonautonomously and can diffuse over the range of several cell diameters. Conceptual translation of the argos gene suggests that it encodes a secreted protein.
A distance regulation method has been developed to enhance the reliability, versatility, and ease of use of near-field scanning optical microscopy (NSOM). The method relies on the detection of shear forces between the end of a near-field probe and the sample of interest. The system can be used solely for distance regulation in NSOM, for simultaneous shear force and near-field imaging, or for shear force microscopy alone. In the latter case, uncoated optical fiber probes are found to yield images with consistently high resolution.
Commentary: To exploit the evanescent field that is the source of high resolution in near-field microscopy, the probe must be exceptionally close to the sample: 10 nm away for 30-50 nm resolution. Here we introduced a distance regulation mechanism based on transverse shear forces between the end of a dithered near-field probe and the sample, which permitted even samples of modest topography to be imaged. Simple, reliable, noninvasive, and applicable to a wide range of samples from whole fixed cells to semiconductor devices, shear force microscopy was a key enabling technology for near-field optics, and soon widely implemented.
1. Perforated patch-clamp recordings were made from the three major classes of hippocampal neurons in conventional in vitro slices prepared from adult guinea pigs. This technique provided experimental estimates of passive membrane properties (input resistance, RN, and membrane time constant, tau m) determined in the absence of the leak conductance associated with microelectrode impalement or the washout of cytoplasmic constituents associated with conventional whole-cell recordings. 2. To facilitate comparison of our data with previous results and to determine the passive membrane properties under conditions as physiological as possible, recordings were made at the resting potential, in physiological saline, and without any added blockers of voltage-dependent conductances. 3. Membrane-potential responses to current steps were analyzed, and four criteria were used to identify voltage responses that were the least affected by activation of voltage-dependent conductances. tau m was estimated from the slowest component (tau 0) of multiexponential fits of responses deemed passive by these criteria. RN was estimated from the slope of the linear region in the hyperpolarizing direction of the voltage-current relation. 4. It was not possible to measure purely passive membrane properties that were completely independent of membrane potential in any of the three classes of hippocampal neurons. Changing the membrane potential by constant current injection resulted in changes in RN and tau 0; subthreshold depolarization produced an increase, and hyperpolarization a decrease, in both RN and tau 0 for all three classes of hippocampal neurons. 5. Each of the three classes of hippocampal neurons also displayed a depolarizing "sag" during larger hyperpolarizing voltage transients. To evaluate the effect of the conductances underlying this sag on passive membrane properties, 2-5 mM Cs+ was added to the physiological saline. Extracellular Cs+ effectively blocked the sag in all three classes of hippocampal neurons, but the effect of Cs+ on RN, tau 0, and the voltage dependence of these parameters was unique for each class of neurons. 6. CA1 pyramidal neurons had an RN of 104 +/- 10 (SE) M omega and tau 0 of 28 +/- 2 ms at a resting potential of -64 +/- 2 mV (n = 12). RN and tau 0 were larger at more depolarized potentials in these neurons, but the addition of Cs+ to the physiological saline reversed this voltage dependence. 7. CA3 pyramidal neurons had an RN of 135 +/- 8 M omega and tau 0 of 66 +/- 4 ms at a resting potential of -64 +/- 1 mV (n = 14).(ABSTRACT TRUNCATED AT 400 WORDS)
Near-field scanning optical microscopy (NSOM) has been used to image and record domains in thin-film magneto-optic (MO) materials. In the imaging mode, resolution of 30-50 nm has been consistently obtained, whereas in the recording mode, domains down to -60 nm have been written reproducibly. Data densities of -45 Gbits/in.’ have been achieved, well in excess of current magnetic or MO technologies. A brief analysis of speed and other issues indicates that the technique may represent a viable alternative to density data storage needs.
Commentary: The first demonstration of optical recording and playback beyond the diffraction limit, using magneto-optic multilayer films and polarization contrast near-field microscopy. Bits as small as 60 nm were recorded – beyond estimates at the time of the superparamagnetic limit to bit stability. Bit densities of 45 Gbits/in2 were also achieved, well in excess of optical or magnetic recording technologies of the era. In the years following this work, massive resources were spent on the commercialization of near-field data storage, largely for naught.