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Ionic Currents Underlying Difference in Light Response Between Type A and Type B Photoreceptors

K. T. Blackwell
2006 Journal of Neurophysiology  
In Hermissenda crassicornis, the memory of light associated with turbulence is stored as changes in intrinsic and synaptic currents in both type A and type B photoreceptors.  ...  The fast spike adaptation required a fast, noninactivating calcium-dependent potassium current.  ...  C: calcium-dependent potassium currents. TABLE 6. Parameters for calcium-dependent potassium currents (Eq.  ... 
doi:10.1152/jn.00780.2005 pmid:16394075 fatcat:3n6yuyxokvfixbormmybqjsxfu

The Effect of Intensity and Duration on the Light-Induced Sodium and Potassium Currents in theHermissendaType B Photoreceptor

Kim T. Blackwell
2002 Journal of Neuroscience  
Furthermore, the contribution of voltage-dependent potassium currents to the long-lasting depolarization in type B photoreceptors depends on light-induced currents active at resting potentials.  ...  Light duration and intensity influence classical conditioning in Hermissenda through their effects on the light-induced currents.  ...  LLD) in response to light (Crow and Alkon, 1980; Farley and Alkon, 1982; West et al., 1982; Frysztak and Crow, 1994) , a reduction in the calcium-dependent, I KC a , and transient, I A , potassium currents  ... 
doi:10.1523/jneurosci.22-10-04217.2002 pmid:12019339 fatcat:nzehdj222va3zko7vnb7eveskm

Comparison ofHermissendaType A and Type B Photoreceptors: Response to Light as a Function of Intensity and Duration

Ji Ling Mo, Kim T. Blackwell
2003 Journal of Neuroscience  
Hermissenda crassicornis is an invertebrate model used to study classical conditioning using light as the conditioned stimulus.  ...  In response to light, the generator potential ( GP) rises linearly with an increase in either intensity or duration for both type A and type B photoreceptors.  ...  In addition to the potassium currents, there are two distinct calcium currents (Yamoah and Crow, 1994; Yamoah et al., 1998) , a transient calcium current and sustained calcium current, in both photoreceptor  ... 
doi:10.1523/jneurosci.23-22-08020.2003 pmid:12954863 fatcat:qrgxqdbsundk3nekcuxcatztua

Voltage-dependent calcium and calcium-activated potassium currents of a molluscan photoreceptor

D.L. Alkon, J. Farley, M. Sakakibara, B. Hay
1984 Biophysical Journal  
Elevation of external potassium allowed the calcium (ICa +) and calcium-dependent K+ (Ic) currents to be substantially separated.  ...  These data suggest that Ic may undergo prolonged inactivation due to a direct effect of elevated intracellular Ca"+, as was previously shown for a voltage-dependent potassium current, IA.  ...  current, and (c) a voltage-dependent outward calcium-dependent potassium current (see also Grossman et al., 1982).  ... 
doi:10.1016/s0006-3495(84)84059-x pmid:6498273 pmcid:PMC1435046 fatcat:t5cv4dr3ovhobalzfmnb6ylt4a

Postsynaptic calcium, but not cumulative depolarization, is necessary for the induction of associative plasticity in Hermissenda

LD Matzel, RF Rogers
1993 Journal of Neuroscience  
{Key words: calcium currents, potassium currents, barium currents, associative learning, memory, long-term potentia· tion, Hermissenda] During associative learning in which light is paired with rota tion  ...  Hermissenda crassicornis (0. 7-1.2 gm) were obtained from Sea Life Supply Co., Sand City CA, and were confined in 12•c artificial sea water (ASW).  ... 
doi:10.1523/jneurosci.13-12-05029.1993 pmid:8254359 fatcat:5mq24ng7h5hz3ox6kvmaoa4y7i

Pavlovian Conditioning of Hermissenda: Current Cellular, Molecular, and Circuit Perspectives

T. Crow
2004 Learning & memory (Cold Spring Harbor, N.Y.)  
The nudibranch mollusk Hermissenda crassicornis is a preparation that has contributed to an understanding of cellular and molecular mechanisms of Pavlovian conditioning.  ...  The less-complex central nervous system of many invertebrates make them attractive for not only the molecular analysis of the associative learning and memory, but also in determining how neural circuits  ...  ACKNOWLEDGMENTS We thank Diana Parker for assistance with the manuscript. This research was supported by National Institutes of Health Grants MH-40860 and MH-58698  ... 
doi:10.1101/lm.70704 pmid:15169851 fatcat:oh5oc4nz4nb6ngqq5shhg6mn7y

AA/12-lipoxygenase signaling contributes to inhibitory learning in Hermissenda Type B photoreceptors

2010 Frontiers in Behavioral Neuroscience  
Type B photoreceptors are a major site of plasticity for classical conditioning in Hermissenda.  ...  We have previously described a simple form of CI learning in Hermissenda, whereby animals' phototactic behavior is increased by repeated exposures to explicitly unpaired (EU) presentations of light and  ...  First, in both invertebrate and vertebrate neurons, AA signaling has often been linked to increases in voltage-and/ or calcium-dependent K + currents.  ... 
doi:10.3389/fnbeh.2010.00050 pmid:20802857 pmcid:PMC2928666 fatcat:stfjotbn5zbmjb5cknj322jaiq

Calcium activates and inactivates a photoreceptor soma potassium current

D.L. Alkon, M. Sakakibara
1985 Biophysical Journal  
In artificial seawater (ASW), light elicited a transient early inward current, INa', which depended on Na' and had a linear current-voltage relation and an extrapolated reversal potential of 30-40 mV (  ...  It was concluded that light, in addition to inducing a transient inward Na+ current, causes both a transient increase and a prolonged decrease of Ic via elevation of Ca +.  ...  nudibranch mollusk Hermissenda crassicornis, primarily as a secondary consequence of light-induced depolarization (Connor and Alkon, 1982, 1984) .  ... 
doi:10.1016/s0006-3495(85)83861-3 pmid:4092073 pmcid:PMC1329431 fatcat:mx6eyyeyljclrbjigjcgwbub7u

Ionic Basis of Learning-Correlated Excitability Changes in Hermissenda Type A Photoreceptors

Joseph Farley, Yunru Han
1997 Journal of Neurophysiology  
Ionic basis of learning-correphotoreceptors is thought to play an important role in learnlated excitability changes in Hermissenda type A photoreceping-produced reductions in phototaxis (Alkon et al. 1985  ...  consequences of changes in type A cell light thereby reduce training-produced differences in amplitude. responses Finally, reduction of [Ca 2/ ] o may increase the light-induced Na / current in Hermissenda  ...  elimination of I A results in greater than normal light-induced vertically.  ... 
doi:10.1152/jn.1997.77.4.1861 pmid:9114242 fatcat:jfzvcndsqbdflfbklyim4djaoa

Protein Tyrosine Kinase Involvement in Learning-Produced Changes in Hermissenda Type B Photoreceptors

Iksung Jin, Haojiang Huang, Benjamin Smith, Joseph Farley
2009 Journal of Neurophysiology  
Learning-correlated changes in the excitability and photoresponses of Hermissenda's ocular type B photoreceptors are mediated by reductions in two distinct K ϩ currents, I A and I K-Ca .  ...  Pervanadate also suppressed I A and I Delayed , reduced their voltage dependence, and altered inactivation kinetics for I A , mimicking conditioning.  ...  A C K N O W L E D G M E N T S We thank the staff at the Friday Harbor Laboratories, University of Washington (Friday Harbor, WA) for providing accommodations that greatly facilitated preparation of the  ... 
doi:10.1152/jn.90732.2008 pmid:19812284 pmcid:PMC2804426 fatcat:z4wl5yxqx5ffjft64rp7kxjhfu

Thirty-Fifth Annual Meeting February 24–28, 1991 Moscone Center San Francisco, California

1991 Biophysical Journal  
(Su9portd by grants fran tha WC, NIH, NDu arS Hvmv) CALCIUM BINDING PROTEINS 2a Site-directed mutagenesis of Drosophila ShakerB within a highly conserved region (H5, 429 to 455) has generated K+ channels  ...  Most conservative single amino acid substitutions did not produce detectable currents.  ...  Associative conditioning of the nudibranch mollusc Hermissenda crassicornis produces a reduction of potassium conductances in the Type B photoreceptors; both the early transient K+ current (IA) and the  ... 
doi:10.1016/s0006-3495(91)82244-5 fatcat:m6juggrf5vfbfcmpsv6fwle2vy

X-ray, spectroscopic and normal-mode dynamics of calexcitin: structure–function studies of a neuronal calcium-signalling protein

P. T. Erskine, A. Fokas, C. Muriithi, H. Rehman, L. A. Yates, A. Bowyer, I. S. Findlow, R. Hagan, J. M. Werner, A. J. Miles, B. A. Wallace, S. A. Wells (+2 others)
2015 Acta Crystallographica Section D: Biological Crystallography  
Subsequent studies showed that calexcitin regulates the voltage-dependent potassium channel and the calcium-dependent potassium channel as well as causing the release of calcium ions from the endoplasmic  ...  There is evidence that the protein has two markedly different affinities for calcium ions, the weaker of which is most likely to be associated with binding of calcium ions to the protein during neuronal  ...  Acknowledgements We thank the BBSRC for a studentship to AB and a project grant to BAW.  ... 
doi:10.1107/s1399004714026704 pmid:25760610 fatcat:anevf5xv2fgxbbn7wmadkuewlq

Auto-phosphorylation of a voltage-gated K+ channel controls non-associative learning

Shi-Qing Cai, Yi Wang, Ki Ho Park, Xin Tong, Zui Pan, Federico Sesti
2009 EMBO Journal  
Genetic, biochemical and electrophysiological evidence show that KHT-1 and MPS-1 form a complex in vitro and in native mechanosensory PLM neurons, and that KHT-1 is a substrate for the kinase activity  ...  In the auto-phosphorylated state the channel acts to induce neuronal adaptation to mechanical stimulation.  ...  We thank Dr John Lenard for critical reading of the manuscript. This work was supported by a NIH grant (R01GM68581) to FS. S-QC and FS designed the research.  ... 
doi:10.1038/emboj.2009.112 pmid:19387491 pmcid:PMC2693150 fatcat:3f6npxu6cva4hd2quexmhveqdq

Twenty-Fifth Annual Meeting February 23–25, 1981 Denver Hilton, Denver, Colorado

1981 Biophysical Journal  
To evaluate these concepts for Na+ transport, the light intensity dependence and action of several membrane transport active agents have been compared.  ...  In the latter respect, fibirs not only differ in intensity of subbands, but a distinction can be made on the basis of the migration velocity of the isozyme multiplet.  ...  We will present evidence that the cessation of current jumps is not due to Ca2+ induced changes in either the vesicles or the planar membrane.  ... 
doi:10.1016/s0006-3495(81)84892-8 fatcat:fqvowhe7vfhihafp7l54xhiete

Twenty-Seventh Annual Meeting February 13–16, 1983 Town & Country Hotel, San Diego, California

1983 Biophysical Journal  
For the working heart perfused with either glucose (15 mM) or pyruvate (10 mM) at 37 C, the flux in the forward direction increased from 22 jsmoles/gram dry weight (gdw/s) in the potassium-arrested heart  ...  In 1968, J.A. Jackson published two papers on the possibility of a whole body NMR spectrometer. Methods were developed for measuring blood flow by NMR in living human arms (Morse, et at 1970).  ...  The type-B photoreceptor soma of Hermissenda crassicornis has both voltage and light dependent K+-conductances.  ... 
doi:10.1016/s0006-3495(83)84424-5 fatcat:n6uk3rs2r5hz3bswrqf2fita64
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