keyword
MENU ▼
Read by QxMD icon Read
search

rhodopsin

keyword
https://www.readbyqxmd.com/read/28337288/which-has-more-stem-cell-characteristics-m%C3%A3-ller-cells-or-m%C3%A3-ller-cells-derived-from-in-vivo-culture-in-neurospheres
#1
Hong-Pei Ji, Yu Xiong, En-Dong Zhang, Wei-Tao Song, Zhao-Lin Gao, Fei Yao, Hong Sun, Rong-Rong Zhou, Xiao-Bo Xia
OBJECTIVE: Müller cells can be acquired from in vitro culture or a neurosphere culture system. Both culture methods yield cells with progenitor-cell characteristics that can differentiate into mature nervous cells. We compared the progenitor-cell traits of Müller cells acquired from each method. METHODS: Primary murine Müller cells were isolated in serum culture media and used to generate Müller cells derived from neurospheres in serum-free culture conditions...
2017: American Journal of Translational Research
https://www.readbyqxmd.com/read/28321183/early-events-in-retinal-degeneration-caused-by-rhodopsin-mutation-or-pigment-epithelium-malfunction-differences-and-similarities
#2
Johnny Di Pierdomenico, Diego García-Ayuso, Isabel Pinilla, Nicolás Cuenca, Manuel Vidal-Sanz, Marta Agudo-Barriuso, María P Villegas-Pérez
To study the course of photoreceptor cell death and macro and microglial reactivity in two rat models of retinal degeneration with different etiologies. Retinas from P23H-1 (rhodopsin mutation) and Royal College of Surgeon (RCS, pigment epithelium malfunction) rats and age-matched control animals (Sprague-Dawley and Pievald Viro Glaxo, respectively) were cross-sectioned at different postnatal ages (from P10 to P60) and rhodopsin, L/M- and S-opsin, ionized calcium-binding adapter molecule 1 (Iba1), glial fibrillary acid protein (GFAP), and proliferating cell nuclear antigen (PCNA) proteins were immunodetected...
2017: Frontiers in Neuroanatomy
https://www.readbyqxmd.com/read/28320964/in-vivo-optophysiology-reveals-that-g-protein-activation-triggers-osmotic-swelling-and-increased-light-scattering-of-rod-photoreceptors
#3
Pengfei Zhang, Robert J Zawadzki, Mayank Goswami, Phuong T Nguyen, Vladimir Yarov-Yarovoy, Marie E Burns, Edward N Pugh
The light responses of rod and cone photoreceptors have been studied electrophysiologically for decades, largely with ex vivo approaches that disrupt the photoreceptors' subretinal microenvironment. Here we report the use of optical coherence tomography (OCT) to measure light-driven signals of rod photoreceptors in vivo. Visible light stimulation over a 200-fold intensity range caused correlated rod outer segment (OS) elongation and increased light scattering in wild-type mice, but not in mice lacking the rod G-protein alpha subunit, transducin (Gαt), revealing these responses to be triggered by phototransduction...
March 20, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28320275/optogenetic-stimulation-increases-level-of-antiapoptotic-protein-bcl-xl-in-neurons
#4
D A Lanshakov, U S Drozd, N N Dygalo
The antiapoptotic protein Bcl-xL is associated with several neuroplastic processes such as formation of synapses, regulation of spontaneous and evoked synaptic responses, and release of neurotransmitters. Dependence of expression on activity of neurons is characteristic for many proteins participating in regulation of neuroplasticity. Whether such property is exhibited by the Bcl-xL protein was analyzed using in vivo optogenetic stimulation of hippocampal glutamatergic neurons expressing channelrhodopsin ChR2H134 under CAMKIIa promoter in the adeno-associated viral vector, followed by immunohistochemical determination of the level of Bcl-xL protein in these neurons and surrounding cells...
March 2017: Biochemistry. Biokhimii︠a︡
https://www.readbyqxmd.com/read/28314815/the-phosphorylation-state-of-the-drosophila-trp-channel-modulates-the-frequency-response-to-oscillating-light-in-vivo
#5
Olaf Voolstra, Elisheva Rhodes-Mordov, Ben Katz, Jonas-Peter Bartels, Claudia Oberegelsbacher, Susanne Katharina Schotthöfer, Bushra Yasin, Hanan Tzadok, Armin Huber, Baruch Minke
Drosophila photoreceptors respond to oscillating light of high frequency (∼100 Hz), while the detected maximal frequency is modulated by the light rearing conditions, thus maintaining high sensitivity to light and high temporal resolution. However, the molecular basis for this adaptive process is unclear. Here, we report that dephosphorylation of the light-activated Transient Receptor Potential (TRP) ion channel at S936 is a fast, graded, light-, and Ca(2+)-dependent process that is partially modulated by the rhodopsin phosphatase Retinal Degeneration C (RDGC)...
March 17, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28302718/a-unique-choanoflagellate-enzyme-rhodopsin-with-cyclic-nucleotide-phosphodiesterase-activity
#6
Kazuho Yoshida, Satoshi P Tsunoda, Leonid S Brown, Hideki Kandori
Photoactivated adenylyl cyclase (PAC) and guanylyl cyclase rhodopsin (Rh-GC) increase the concentrations of intracellular cyclic nucleotides upon illumination, serving as promising second-generation tools in optogenetics. To broaden arsenal of such tools, it is desirable to have light-activatable enzymes which can decrease cyclic nucleotide concentrations in cells. Here, we report on an unusual microbial rhodopsin which may be able to meet the demand. It is found in the choanoflagellate Salpingoeca rosetta and contains a C-terminal cyclic nucleotide phosphodiesterase (PDE) domain...
March 16, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28301742/microbial-rhodopsins-diversity-mechanisms-and-optogenetic-applications
#7
Elena G Govorunova, Oleg A Sineshchekov, Hai Li, John L Spudich
Microbial rhodopsins are a family of photoactive retinylidene proteins widespread throughout the microbial world. They are notable for their diversity of function, using variations of a shared seven-transmembrane helix design and similar photochemical reactions to carry out distinctly different light-driven energy and sensory transduction processes. Their study has contributed to our understanding of how evolution modifies protein scaffolds to create new protein chemistry, and their use as tools to control membrane potential with light is fundamental to optogenetics for research and clinical applications...
March 9, 2017: Annual Review of Biochemistry
https://www.readbyqxmd.com/read/28300845/digoxin-induced-retinal-degeneration-depends-on-rhodopsin
#8
Britta Landfried, Marijana Samardzija, Maya Barben, Christian Schori, Katrin Klee, Federica Storti, Christian Grimm
Na,K-ATPases are energy consuming ion pumps that are required for maintaining ion homeostasis in most cells. In the retina, Na,K-ATPases are especially important to sustain the dark current in photoreceptor cells needed for rapid hyperpolarization of rods and cones in light. Cardiac glycosides like digoxin inhibit the activity of Na,K-ATPases by targeting their catalytic alpha subunits. This leads to a disturbed ion balance, which can affect cellular function and survival. Here we show that the treatment of wild-type mice with digoxin leads to severe retinal degeneration and loss of vision...
March 16, 2017: Cell Death & Disease
https://www.readbyqxmd.com/read/28290523/a-phylogenetically-distinctive-and-extremely-heat-stable-light-driven-proton-pump-from-the-eubacterium-rubrobacter-xylanophilus-dsm-9941-t
#9
Kanae Kanehara, Susumu Yoshizawa, Takashi Tsukamoto, Yuki Sudo
Rhodopsins are proteins that contain seven transmembrane domains with a chromophore retinal and that function as photoreceptors for light-energy conversion and light-signal transduction in a wide variety of organisms. Here we characterized a phylogenetically distinctive new rhodopsin from the thermophilic eubacterium Rubrobacter xylanophilus DSM 9941(T) that was isolated from thermally polluted water. Although R. xylanophilus rhodopsin (RxR) is from Actinobacteria, it is located between eukaryotic and archaeal rhodopsins in the phylogenetic tree...
March 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28289782/neuro-psychopharmacological-perspective-of-orphan-receptors-of-rhodopsin-class-a-family-of-g-protein-coupled-receptors
#10
REVIEW
Muhammad Zahid Khan, Ling He
BACKGROUND: In the central nervous system (CNS), G protein-coupled receptors (GPCRs) are the most fruitful targets for neuropsychopharmacological drug development. Rhodopsin (class A) is the most studied class of GPCR and includes orphan receptors for which the endogenous ligand is not known or is unclear. Characterization of orphan GPCRs has proven to be challenging, and the production pace of GPCR-based drugs has been incredibly slow. OBJECTIVE: Determination of the functions of these receptors may provide unexpected insight into physiological and neuropathological processes...
March 13, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28289214/photocyclic-behavior-of-rhodopsin-induced-by-an-atypical-isomerization-mechanism
#11
Sahil Gulati, Beata Jastrzebska, Surajit Banerjee, Ángel L Placeres, Przemyslaw Miszta, Songqi Gao, Karl Gunderson, Gregory P Tochtrop, Sławomir Filipek, Kota Katayama, Philip D Kiser, Muneto Mogi, Phoebe L Stewart, Krzysztof Palczewski
Vertebrate rhodopsin (Rh) contains 11-cis-retinal as a chromophore to convert light energy into visual signals. On absorption of light, 11-cis-retinal is isomerized to all-trans-retinal, constituting a one-way reaction that activates transducin (Gt) followed by chromophore release. Here we report that bovine Rh, regenerated instead with a six-carbon-ring retinal chromophore featuring a C(11)=C(12) double bond locked in its cis conformation (Rh6mr), employs an atypical isomerization mechanism by converting 11-cis to an 11,13-dicis configuration for prolonged Gt activation...
March 13, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28288836/temporal-profiling-of-photoreceptor-lineage-gene-expression-during-murine-retinal-development
#12
Tooka Aavani, Nobuhiko Tachibana, Valerie Wallace, Jeffrey Biernaskie, Carol Schuurmans
Rod and cone photoreceptors are photosensitive cells in the retina that convert light to electrical signals that are transmitted to visual processing centres in the brain. During development, cones and rods are generated from a common pool of multipotent retinal progenitor cells (RPCs) that also give rise to other retinal cell types. Cones and rods differentiate in two distinct waves, peaking in mid-embryogenesis and the early postnatal period, respectively. As RPCs transition from making cones to generating rods, there are changes in the expression profiles of genes involved in photoreceptor cell fate specification and differentiation...
March 10, 2017: Gene Expression Patterns: GEP
https://www.readbyqxmd.com/read/28274625/apd668-a-g-protein-coupled-receptor-119-agonist-improves-fat-tolerance-and-attenuates-fatty-liver-in-high-trans-fat-diet-induced-steatohepatitis-model-in-c57bl-6-mice
#13
Umakant Ashok Bahirat, Rekha Raghuveer Shenoy, Rajan Naresh Goel, Kumar V S Nemmani
G-protein coupled receptor 119 (GPR119) receptor is a rhodopsin-like, class A Gαs-coupled receptor, predominantly expressed in pancreatic islet cells and intestinal entero-endocrine cells. GPR119 has been emerged as a novel therapeutic target for the treatment of dyslipidemia in type 2 diabetes. In this study, we investigated the effect of APD668, a GPR119 agonist alone and in combination with linagliptin, a DPPIV inhibitor on oral fat tolerance test. Our findings demonstrate that APD668, a GPR119 agonist inhibits the intestinal triglyceride absorption after acute fat load in mice...
March 6, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28262559/directed-evolution-of-a-bright-near-infrared-fluorescent-rhodopsin-using-a-synthetic-chromophore
#14
Lukas Herwig, Austin J Rice, Claire N Bedbrook, Ruijie K Zhang, Antti Lignell, Jackson K B Cahn, Hans Renata, Sheel C Dodani, Inha Cho, Long Cai, Viviana Gradinaru, Frances H Arnold
By engineering a microbial rhodopsin, Archaerhodopsin-3 (Arch), to bind a synthetic chromophore, merocyanine retinal, in place of the natural chromophore all-trans-retinal (ATR), we generated a protein with exceptionally bright and unprecedentedly red-shifted near-infrared (NIR) fluorescence. We show that chromophore substitution generates a fluorescent Arch complex with a 200-nm bathochromic excitation shift relative to ATR-bound wild-type Arch and an emission maximum at 772 nm. Directed evolution of this complex produced variants with pH-sensitive NIR fluorescence and molecular brightness 8...
March 16, 2017: Cell Chemical Biology
https://www.readbyqxmd.com/read/28258056/novel-immunodeficient-pde6b-rd1-mouse-model-of-retinitis-pigmentosa-to-investigate-potential-therapeutics-and-pathogenesis-of-retinal-degeneration
#15
Alaknanda Mishra, Barun Das, Madhu Nath, Srikanth Iyer, Ashwani Kesarwani, Jashdeep Bhattacharjee, Shailendra Arindkar, Preeti Sahay, Kshama Jain, Parul Sahu, Prakriti Sinha, Thirumurthy Velpandian, Perumal Nagarajan, Pramod Upadhyay
Retinitis pigmentosa (RP) is a common retinal degeneration disease caused by mutation in any gene of the photo transduction cascade and results in photoreceptor dystrophy. Over decades, several animal models have been used to address the need for elucidation of effective therapeutics and factors regulating retinal degeneration to prohibit or renew the damaged retina. However, controversies over immune privilege of retina during cell transplantation and role of immune modulation during RP still remain largely uninvestigated due to lack of proper animal models...
March 3, 2017: Biology Open
https://www.readbyqxmd.com/read/28257611/demonstration-of-a-light-driven-so4-2-transporter-and-its-spectroscopic-characteristics
#16
Akiko Niho, Susumu Yoshizawa, Takashi Tsukamoto, Marie Kurihara, Shinya Tahara, Yu Nakajima, Misao Mizuno, Hikaru Kuramochi, Tahei Tahara, Yasuhisa Mizutani, Yuki Sudo
In organisms, ion transporters play essential roles in the generation and dissipation of ion gradients across cell membranes. Microbial rhodopsins selectively transport cognate ions using solar energy, in which the substrate ions identified to date have been confined to monovalent ions such as H(+), Na(+), and Cl(-). Here we report a novel rhodopsin from the cyanobacterium Synechocystis sp. PCC 7509, which inwardly transports a polyatomic divalent sulfate ion, SO4(2-), with changes of its spectroscopic properties in both unphotolyzed and photolyzed states...
March 16, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28256796/human-limbal-neurospheres-prevent-photoreceptor-cell-death-in-a-rat-model-of-retinal-degeneration
#17
Samuel McLenachan, Dan Zhang, Erwei Hao, Ling Zhang, Shang-Chih Chen, Fred K Chen
BACKGROUND: The culture of retinal progenitors from an accessible adult stem cell source such as the limbus could provide a useful autologous source of retinal cell therapies. The human corneoscleral limbus contains multipotent stem cells that can be cultured as floating neurospheres. Previous work in rodents has demonstrated neuronal and photoreceptor differentiation from limbal neurosphere cultures. Here, we have examined undifferentiated cultured adult human limbal neurospheres as donor cells for retinal cell therapies by transplantation into a rat model of retinal degeneration...
March 3, 2017: Clinical & Experimental Ophthalmology
https://www.readbyqxmd.com/read/28253405/contributions-of-second-and-third-order-retinal-neurons-to-cone-electroretinograms-after-loss-of-rod-function-in-rhodopsin-p347l-transgenic-rabbits
#18
Taro Kominami, Shinji Ueno, Satoshi Okado, Ayami Nakanishi, Mineo Kondo, Hiroko Terasaki
Purpose: To determine the contribution of second- and third-order retinal neurons to the photopic electroretinograms (ERGs) after the degeneration of the rods in rhodopsin P347L transgenic rabbits (Tg). Methods: Four wild-type (WT) rabbits and four Tg rabbits were studied at 18 months of age. The photopic ERGs elicited at stimulus onset and offset were analyzed. To block different retinal pathways, 2-amino-4-phosphonobutyric acid (APB), 6-cyano-7-nitroquinoxaline-2, 3 (1H,4H)-dione (CNQX), tetrodotoxin (TTX), and N-methyl-DL-aspartic acid (NMDA) were injected intravitreally...
March 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28251753/optomechanical-control-of-quantum-yield-in-trans-cis-ultrafast-photoisomerization-of-a-retinal-chromophore-model
#19
Alessio Valentini, Daniel Rivero, Felipe Zapata, Cristina García-Iriepa, Marco Marazzi, Raúl Palmeiro, Ignacio Fdez Galván, Diego Sampedro, Massimo Olivucci, Luis Manuel Frutos
The quantum yield of a photochemical reaction is one of the most fundamental quantities in photochemistry, as it measures the efficiency of the transduction of light energy into chemical energy. Nature has evolved photoreceptors in which the reactivity of a chromophore is enhanced by its molecular environment to achieve high quantum yields. The retinal chromophore sterically constrained inside rhodopsin proteins represents an outstanding example of such a control. In a more general framework, mechanical forces acting on a molecular system can strongly modify its reactivity...
March 2, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28250185/epistatic-interactions-influence-terrestrial-marine-functional-shifts-in-cetacean-rhodopsin
#20
Sarah Z Dungan, Belinda S W Chang
Like many aquatic vertebrates, whales have blue-shifting spectral tuning substitutions in the dim-light visual pigment, rhodopsin, that are thought to increase photosensitivity in underwater environments. We have discovered that known spectral tuning substitutions also have surprising epistatic effects on another function of rhodopsin, the kinetic rates associated with light-activated intermediates. By using absorbance spectroscopy and fluorescence-based retinal release assays on heterologously expressed rhodopsin, we assessed both spectral and kinetic differences between cetaceans (killer whale) and terrestrial outgroups (hippo, bovine)...
March 15, 2017: Proceedings. Biological Sciences
keyword
keyword
86950
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"