Group III Metabotropic Glutamate Receptors and Exocytosed Protons Inhibit L-Type Calcium Currents in Cones But Not in Rods

Hosoi, Nobutake; Arai, Iwao; Tachibana, Makoto

doi:10.1523/jneurosci.2735-04.2005

Cited by 56 publications

(39 citation statements)

References 91 publications

(109 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since glutamate is the main neurotransmitter in the retina, various mGluRs can be found in the eye of vertebrates, where they have been shown to be involved in signal modulation at the first visual synapse (Rothe et al, 1994;Linn and Gafka, 1999;Hirasawa et al, 2002;Hosoi et al, 2005;Fan and Yazulla, 2007). However, we found expression for most zebrafish mglurs in the inner retina but not in the outermost layers where photoreceptors (ONL) and horizontal cell bodies (outermost INL close to OPL) are located.…”

Section: Retinamentioning

confidence: 60%

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Haug

Gesemann

Mueller

2013

J of Comparative Neurology

View full text Add to dashboard Cite

Glutamate, the most abundant excitatory neurotransmitter of the central nervous system, modulates synaptic transmission and neuronal excitability via metabotropic glutamate receptors (mGluRs). These receptors are essential components for diverse cognitive functions and they represent potential drug targets for the treatment of a number of neurological and psychiatric disorders. Here, we describe the phylogenetic relation and mRNA distribution of zebrafish mGluRs. In comparison to the eight mglurs present in the mammalian genome, we identified 13 different mglur genes in the zebrafish genome. In situ hybridization experiments in zebrafish revealed widespread expression patterns for the different mglurs in the central nervous system, implicating their significance in diverse neuronal functions. Prominent mglur expression is found in the olfactory bulb, the optic tectum, the hypothalamus, the cerebellum, and the retina. We show that expression pattern of paralogs generated by the teleost specific whole genome duplication is overlapping in some brain regions but complementary in others, suggesting sub-and/or neofunctionalization in the latter. Group I mglurs are similarly expressed in brain areas of both larval and adult zebrafish, suggesting that their functions are comparable during these stages. AbstractGlutamate, the most abundant excitatory neurotransmitter of the central nervous system, modulates synaptic transmission and neuronal excitability via metabotropic glutamate receptors (mGluRs). These receptors are essential components for diverse cognitive functions and they represent potential drug targets for the treatment of a number of neurological and psychiatric disorders.Here, we describe the phylogenetic relation and mRNA distribution of zebrafish mGluRs. In comparison to the eight mglurs present in the mammalian genome, we identified 13 different mglur genes in the zebrafish genome. In situ hybridization experiments in zebrafish revealed widespread expression patterns for the different mglurs in the central nervous system, implicating their significance in diverse neuronal functions. Prominent mglur expression is found in the olfactory bulb, the optic tectum, the hypothalamus, the cerebellum, and the retina. We show that expression pattern of paralogs generated by the teleost specific whole genome duplication is overlapping in some brain regions but complementary in others, suggesting suband/or neofunctionalization in the latter. Group I mglurs are similarly expressed in brain areas of both larval and adult zebrafish, suggesting that their functions are comparable during these stages.

show abstract

Section: Retinamentioning

confidence: 60%

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Haug

Gesemann

Mueller

2013

J of Comparative Neurology

View full text Add to dashboard Cite

show abstract

“…Use-dependent feedback mechanisms include voltage-and calcium-dependent inhibition of I Ca [140][141][142][143], inhibition of cone I Ca by the pre-synaptic actions of glutamate on group III mGluRs [208], inhibition of cone I Ca by vesicular protons [208,209], inhibition of I Ca by vesicular zinc [116,210,211], inhibitory effects of adenosine which can be derived from vesicular ATP [212][213][214], inhibition of rod I Ca due to chloride efflux mediated by pre-synaptic glutamate transporters [215], inhibition of rod I Ca due to chloride efflux through calcium-activated chloride channels [138], and enhancement of rod I Ca due to K+ efflux through calcium-activated potassium channels [19]. Various neurotransmitters and neuromodulators also regulate rod and cone I Ca , including nitric oxide [216,217], dopamine [132], cannabinoids [218][219][220], somatostatin [221], insulin [222], retinoids, and polyunsaturated fats [223].…”

Section: Synaptic Depression and Vesicle Replenishmentmentioning

confidence: 99%

Kinetics of Synaptic Transmission at Ribbon Synapses of Rods and Cones

Thoreson

2007

Mol Neurobiol

View full text Add to dashboard Cite

The ribbon synapse is a specialized structure that allows photoreceptors to sustain the continuous release of vesicles for hours upon hours and years upon years but also respond rapidly to momentary changes in illumination. Light responses of cones are faster than those of rods and, mirroring this difference, synaptic transmission from cones is also faster than transmission from rods. This review evaluates the various factors that regulate synaptic kinetics and contribute to kinetic differences between rod and cone synapses. Presynaptically, the release of glutamate-laden synaptic vesicles is regulated by properties of the synaptic proteins involved in exocytosis, influx of calcium through calcium channels, calcium release from intracellular stores, diffusion of calcium to the release site, calcium buffering, and extrusion of calcium from the cytoplasm. The rate of vesicle replenishment also limits the ability of the synapse to follow changes in release. Post-synaptic factors include properties of glutamate receptors, dynamics of glutamate diffusion through the cleft, and glutamate uptake by glutamate transporters. Thus, multiple synaptic mechanisms help to shape the responses of second-order horizontal and bipolar cells. KeywordsPhotoreceptor; Synaptic transmission; Glutamate; Calcium; Vesicles; Retina Vision begins with the transduction of light into membrane potential changes as the result of an enzymatic cascade occurring in the outer segments of rod and cone photoreceptors [1,2]. Light-evoked membrane potential changes are modified by voltage-dependent currents in the inner segment [3] and transmitted to second order bipolar and horizontal cells by changes in release of the neurotransmitter, L-glutamate, from the synaptic terminals of both rods and cones. Because all of the visual information available to downstream retinal neurons must first pass through the photoreceptor synapse, synaptic transmission from photoreceptors has a considerable impact on visual perception. The focus of this review is on mechanisms that shape the kinetics of synaptic transmission at synapses of rods and cones. Additional information on other physiological and anatomical characteristics of photoreceptor ribbon synapses can be found in recent reviews [4][5][6]. Differences in Rod and Cone KineticsRod and cone photoreceptors are tonically depolarized in darkness with membrane potentials of −35 to −45 mV that allow continuous release of the neurotransmitter, L-glutamate. Light onset causes photoreceptors to hyperpolarize by as much as 30 mV, leading to a reduction in

show abstract

“…This could reflect differences in Ca 2ϩ entry or removal from the cytoplasm. Although rods and cones exhibit some differences in L-type Ca 2ϩ -channel subtypes (Morgans et al, 2005), the voltage dependence of activation is similar in dissociated rods and cones (Corey et al, 1984;Maricq and Korenbrot, 1988;Barnes and Hille, 1989;Rieke and Schwartz, 1994;Wilkinson and Barnes, 1996;Savchenko et al, 1997;Hosoi et al, 2005). However, the Ca 2ϩ current in cone, but not rod terminals is modulated by horizontal cell feedback (Verweij et al, 1996;Cadetti and Thoreson, 2006), so in the intact retina, the voltagedependent activation of rod and cone Ca 2ϩ current may differ substantially.…”

Section: Mechanisms Underlying Slower Dark Release From Rodsmentioning

confidence: 99%

“…However, the Ca 2ϩ current in cone, but not rod terminals is modulated by horizontal cell feedback (Verweij et al, 1996;Cadetti and Thoreson, 2006), so in the intact retina, the voltagedependent activation of rod and cone Ca 2ϩ current may differ substantially. Moreover, group III metabotropic glutamate receptors and exocytosed protons can modulate the Ca 2ϩ current of cones, but not rods (Hosoi et al, 2005). L-type Ca 2ϩ channels are the sole pathway for extracellular Ca 2ϩ entry in rods, but cyclic nucleotide-gated channels also contribute to Ca 2ϩ influx in cones (Rieke and Schwartz, 1994;Savchenko et al, 1997).…”

Section: Mechanisms Underlying Slower Dark Release From Rodsmentioning

confidence: 99%

Synaptic Ca²⁺in Darkness Is Lower in Rods than Cones, Causing Slower Tonic Release of Vesicles

Sheng¹,

Choi²,

Dharia³

et al. 2007

J. Neurosci.

View full text Add to dashboard Cite

Rod and cone photoreceptors use specialized biochemistry to generate light responses that differ in their sensitivity and kinetics. However, it is unclear whether there are also synaptic differences that affect the transmission of visual information. Here, we report that in the dark, rods tonically release synaptic vesicles at a much slower rate than cones, as measured by the release of the fluorescent vesicle indicator FM1-43. To determine whether slower release results from a lower Ca 2ϩ sensitivity or a lower dark concentration of Ca 2ϩ , we imaged fluorescent indicators of synaptic vesicle cycling and intraterminal Ca 2ϩ . We report that the Ca 2ϩ sensitivity of release is indistinguishable in rods and cones, consistent with their possessing similar release machinery. However, the dark intraterminal Ca 2ϩ concentration is lower in rods than in cones, as determined by two-photon Ca 2ϩ imaging. The lower level of dark Ca 2ϩ ensures that rods encode intensity with a slower vesicle release rate that is better matched to the lower information content of dim light.

show abstract

Group III Metabotropic Glutamate Receptors and Exocytosed Protons Inhibit L-Type Calcium Currents in Cones But Not in Rods

Cited by 56 publications

References 91 publications

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Kinetics of Synaptic Transmission at Ribbon Synapses of Rods and Cones

Synaptic Ca²⁺in Darkness Is Lower in Rods than Cones, Causing Slower Tonic Release of Vesicles

Contact Info

Product

Resources

About

Group III Metabotropic Glutamate Receptors and Exocytosed Protons Inhibit L-Type Calcium Currents in Cones But Not in Rods

Cited by 56 publications

References 91 publications

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Phylogeny and expression divergence of metabotropic glutamate receptor genes in the brain of zebrafish (Danio rerio)

Kinetics of Synaptic Transmission at Ribbon Synapses of Rods and Cones

Synaptic Ca2+in Darkness Is Lower in Rods than Cones, Causing Slower Tonic Release of Vesicles

Contact Info

Product

Resources

About

Synaptic Ca²⁺in Darkness Is Lower in Rods than Cones, Causing Slower Tonic Release of Vesicles