scholarly journals Non-invasive red-light optogenetic control of Drosophila cardiac function

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jing Men ◽  
Airong Li ◽  
Jason Jerwick ◽  
Zilong Li ◽  
Rudolph E. Tanzi ◽  
...  
Keyword(s):  
Blue Light ◽  
Developmental Stages ◽  
Genetic Model ◽  
Imaging System ◽  
Red Light ◽  
Heart Rhythm ◽  
Light Stimulation ◽  
Excitation Light ◽  
Non Invasive ◽  
Recovery Dynamics

AbstractDrosophila is a powerful genetic model system for cardiovascular studies. Recently, optogenetic pacing tools have been developed to control Drosophila heart rhythm noninvasively with blue light, which has a limited penetration depth. Here we developed both a red-light sensitive opsin expressing Drosophila system and an integrated red-light stimulation and optical coherence microscopy (OCM) imaging system. We demonstrated noninvasive control of Drosophila cardiac rhythms using a single light source, including simulated tachycardia in ReaChR-expressing flies and bradycardia and cardiac arrest in halorhodopsin (NpHR)-expressing flies at multiple developmental stages. By using red excitation light, we were able to pace flies at higher efficiency and with lower power than with equivalent blue light excitation systems. The recovery dynamics after red-light stimulation of NpHR flies were observed and quantified. The combination of red-light stimulation, OCM imaging, and transgenic Drosophila systems provides a promising and easily manipulated research platform for noninvasive cardiac optogenetic studies.

scholarly journals Non-invasive red-light optogenetic control of Drosophila cardiac function

2020 ◽  
Author(s):  
Jing Men ◽  
Airong Li ◽  
Jason Jerwick ◽  
Zilong Li ◽  
Rudolph E. Tanzi ◽  
...  
Keyword(s):  
Blue Light ◽  
Developmental Stages ◽  
Genetic Model ◽  
Imaging System ◽  
Red Light ◽  
Heart Rhythm ◽  
Light Stimulation ◽  
Excitation Light ◽  
Non Invasive ◽  
Recovery Dynamics

ABSTRACTDrosophila is a powerful genetic model system for cardiovascular studies. Recently, optogenetic pacing tools have been developed to control Drosophila heart rhythm noninvasively with blue light, which has a limited penetration depth. Here we developed both a red-light sensitive opsin expressing Drosophila system and an integrated red-light stimulation and optical coherence microscopy (OCM) imaging system. We demonstrated noninvasive control of Drosophila cardiac rhythms, including simulated tachycardia in ReaChR-expressing flies and bradycardia and cardiac arrest in halorhodopsin (NpHR)-expressing flies at multiple developmental stages. By using red excitation light, we were able to pace flies at higher efficiency and with lower power than with equivalent blue light excitation systems. The recovery dynamics after red-light stimulation of NpHR flies were observed and quantified. The combination of red-light stimulation, OCM imaging, and transgenic Drosophila systems provides a promising and easily manipulated research platform for noninvasive cardiac optogenetic studies.

scholarly journals Intraoperative Fluorescence Cerebral Angiography by Laser Surgical Microscopy: Comparison With Xenon Microscopy and Simultaneous Observation of Cerebral Blood Flow and Surrounding Structures

2018 ◽  
Vol 16 (6) ◽  
pp. 700-706 ◽  
Author(s):  
Yuhei Ito ◽  
Kyouichi Suzuki ◽  
Tsuyoshi Ichikawa ◽  
Yoichi Watanabe ◽  
Taku Sato ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blue Light ◽  
Cerebral Angiography ◽  
Red Light ◽  
Fluorescence Angiography ◽  
Sodium Fluorescein ◽  
Simultaneous Observation ◽  
Excitation Light ◽  
Laser Illumination

Abstract BACKGROUND Laser surgical microscopes should enable uniform illumination of the operative field, and require less luminous energy compared with existing xenon surgical microscopes. OBJECTIVE To examine the utility of laser illumination in fluorescence cerebral angiography. METHODS Fluorescein sodium (fluorescein) was used as a fluorescent dye. We first compared the clarity of cerebral blood flow images collected by fluorescence angiography between the laser illumination and xenon illumination methods. We then assessed use of the laser illuminator for simultaneous observation of blood flow and surrounding structures during fluorescence angiography. Furthermore, the study was designed to evaluate usefulness of the thus determined excitation light in clinical cases. RESULTS Fluorescence angiography using blue light laser for excitation provided higher clarity and contrast blood flow images compared with using blue light generated from a xenon lamp. Further, illumination with excitation light consisting of a combination of 3 types of laser (higher level of blue light, no green light, and lower level of red light) enabled both blood flow and surrounding structures to be observed through the microscope directly by the surgeon. CONCLUSION Laser-illuminated fluorescence angiography provides high clarity and contrast images of cerebral blood flow. Further, a laser providing strong blue light and weak red light for excitation light enables simultaneous visual observation of fluorescent blood flow and surrounding structures by the surgeon using a surgical microscope. Overall, these data suggest that laser surgical microscopes are useful for both ordinary operative manipulations and fluorescence angiography.

scholarly journals Transcriptome Analysis Reveals Candidate Genes Involved in Light-Induced Primordium Differentiation in Pleurotus eryngii

2021 ◽  
Vol 23 (1) ◽  
pp. 435
Author(s):  
Dou Ye ◽  
Fang Du ◽  
Qingxiu Hu ◽  
Yajie Zou ◽  
Xue Bai
Keyword(s):  
Blue Light ◽  
High Throughput Sequencing ◽  
Expression Profiles ◽  
Red Light ◽  
Enrichment Analysis ◽  
Mapk Signaling ◽  
Pleurotus Eryngii ◽  
Light Stimulation ◽  
Edible Fungus ◽  
Oxidative Phosphorylation Pathway

Pleurotus eryngii, a highly valued edible fungus, is one of the major commercially cultivated mushrooms in China. The development of P. eryngii, especially during the stage of primordium differentiation, is easily affected by light. However, the molecular mechanism underlying the response of primordium differentiation to light remains unknown. In the present study, primordium expression profiles under blue-light stimulation, red-light stimulation, and exposure to darkness were compared using high-throughput sequencing. A total of 16,321 differentially expressed genes (DEGs) were identified from three comparisons. GO enrichment analysis showed that a large number of DEGs were related to light stimulation and amino acid biosynthesis. KEGG analyses demonstrated that the MAPK signaling pathway, oxidative phosphorylation pathway, and RNA transport were most active during primordium differentiation. Furthermore, it was predicted that the blue-light photoreceptor WC-1 and Deoxyribodipyrimidine photolyase PHR play important roles in the primordium differentiation of P. eryngii. Taken together, the results of this study provide a speculative mechanism that light induces primordium differentiation and a foundation for further research on fruiting body development in P. eryngii.

scholarly journals The Influence of New Colored Light Stimulation Methods on Heart Rate Variability, Temperature, and Well-Being: Results of a Pilot Study in Humans

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Daniela Litscher ◽  
Lu Wang ◽  
Ingrid Gaischek ◽  
Gerhard Litscher
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Pilot Study ◽  
Blue Light ◽  
Red Light ◽  
Well Being ◽  
Light Stimulation ◽  
State Of Mind ◽  
Environmental Stimulation ◽  
Nose Temperature

Changes of light intensity of different colors can shift many physiological parameters and conditions like melatonin, alertness, body temperature, heart rate (HR), and heart rate variability (HRV). The aim of this pilot study was to investigate acute temperature, HR, HRV, and state of mind reactivities after illumination with red (631 nm) and blue (456 nm) light (illuminance 140 lux for both). Seven healthy volunteers (5 females, 2 males; mean age ± SD 34.1 ± 11.9 years) were investigated at the Medical University of Graz, using new color light panels. Significant decreases were found only after 10 min blue light stimulation in nose temperature (P=0.046), HR (P<0.05), and total HRV (P=0.029), in association with a significant alteration of the emotional state (stress level score,P=0.006). However, red light stimulation of the same persons did not induce the same effects in these parameters. The effect of blue light as environmental stimulation on human health is not clarified in detail and needs further investigations.

scholarly journals Identification of a dual orange/far-red and blue light photoreceptor from an oceanic green picoplankton

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuko Makita ◽  
Shigekatsu Suzuki ◽  
Keiji Fushimi ◽  
Setsuko Shimada ◽  
Aya Suehisa ◽  
...  
Keyword(s):  
Blue Light ◽  
Light Adaptation ◽  
Developmental Stages ◽  
Red Light ◽  
Light Harvesting Complex ◽  
Light Sensing ◽  
Light Spectra ◽  
Wide Range ◽  
Marine Metagenome ◽  
Environmental Adaptability

AbstractPhotoreceptors are conserved in green algae to land plants and regulate various developmental stages. In the ocean, blue light penetrates deeper than red light, and blue-light sensing is key to adapting to marine environments. Here, a search for blue-light photoreceptors in the marine metagenome uncover a chimeric gene composed of a phytochrome and a cryptochrome (Dualchrome1, DUC1) in a prasinophyte, Pycnococcus provasolii. DUC1 detects light within the orange/far-red and blue spectra, and acts as a dual photoreceptor. Analyses of its genome reveal the possible mechanisms of light adaptation. Genes for the light-harvesting complex (LHC) are duplicated and transcriptionally regulated under monochromatic orange/blue light, suggesting P. provasolii has acquired environmental adaptability to a wide range of light spectra and intensities.

scholarly journals Unveiling of a novel bifunctional photoreceptor, Dualchrome1, isolated from a cosmopolitan green alga

2020 ◽  
Author(s):  
Yuko Makita ◽  
Shigekatsu Suzuki ◽  
Keiji Fushimi ◽  
Setsuko Shimada ◽  
Aya Suehisa ◽  
...  
Keyword(s):  
Blue Light ◽  
Light Adaptation ◽  
Developmental Stages ◽  
Red Light ◽  
Pheophorbide A ◽  
Light Harvesting Complex ◽  
Light Sensing ◽  
Light Spectra ◽  
Wide Range ◽  
Marine Metagenome

Abstract Photoreceptors are conserved in green algae to land plants, and regulate various developmental stages. In the ocean, blue light penetrates deeper than red light, and blue-light sensing is key to adapting to marine environments. A search for blue-light photoreceptors in the marine metagenome uncovered a novel chimeric gene composed of a phytochrome and a cryptochrome (Dualchrome1, DUC1) in a prasinophyte, Pycnococcus provasolii. DUC1 detects light within the orange/far-red and blue spectra, and acts as a dual photoreceptor. Its complete genome revealed that P. provasolii facilitates light adaptation mechanisms via pheophorbide a oxygenase (Pao) and prasinoxanthin. Genes for the light-harvesting complex (LHC) are duplicated and transcriptionally regulated under monochromatic orange/blue light, suggesting P. provasolii has acquired environmental adaptability to a wide range of light spectra and intensities.

scholarly journals Optogenetic pacing in Drosophila melanogaster

2015 ◽  
Vol 1 (9) ◽  
pp. e1500639 ◽  
Author(s):  
Aneesh Alex ◽  
Airong Li ◽  
Rudolph E. Tanzi ◽  
Chao Zhou
Keyword(s):  
Drosophila Melanogaster ◽  
Electrical Stimulation ◽  
High Speed ◽  
Developmental Stages ◽  
Imaging System ◽  
Model Organism ◽  
Heart Rhythm ◽  
Cardiac Pacing ◽  
Microscopy Imaging ◽  
Cardiac Tissues

Electrical stimulation is currently the gold standard for cardiac pacing. However, it is invasive and nonspecific for cardiac tissues. We recently developed a noninvasive cardiac pacing technique using optogenetic tools, which are widely used in neuroscience. Optogenetic pacing of the heart provides high spatial and temporal precisions, is specific for cardiac tissues, avoids artifacts associated with electrical stimulation, and therefore promises to be a powerful tool in basic cardiac research. We demonstrated optogenetic control of heart rhythm in a well-established model organism, Drosophila melanogaster. We developed transgenic flies expressing a light-gated cation channel, channelrhodopsin-2 (ChR2), specifically in their hearts and demonstrated successful optogenetic pacing of ChR2-expressing Drosophila at different developmental stages, including the larva, pupa, and adult stages. A high-speed and ultrahigh-resolution optical coherence microscopy imaging system that is capable of providing images at a rate of 130 frames/s with axial and transverse resolutions of 1.5 and 3.9 μm, respectively, was used to noninvasively monitor Drosophila cardiac function and its response to pacing stimulation. The development of a noninvasive integrated optical pacing and imaging system provides a novel platform for performing research studies in developmental cardiology.

scholarly journals Phototropin 1 and dim-blue light modulate the red light de-etiolation response

2014 ◽  
Vol 9 (11) ◽  
pp. e976158
Author(s):  
Yihai Wang ◽  
Kevin M Folta
Keyword(s):  
Blue Light ◽  
Red Light

scholarly journals Single Wavelengths of LED Light Supplement Promote the Biosynthesis of Major Cyclic Monoterpenes in Japanese Mint

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1420
Author(s):  
Takahiro Ueda ◽  
Miki Murata ◽  
Ken Yokawa
Keyword(s):  
Blue Light ◽  
Solid Phase ◽  
Glandular Trichomes ◽  
Red Light ◽  
Glandular Trichome ◽  
Pulse Amplitude ◽  
Light Treatment ◽  
Led Light ◽  
Trichome Formation ◽  
Japanese Mint

Environmental light conditions influence the biosynthesis of monoterpenes in the mint plant. Cyclic terpenes, such as menthol, menthone, pulegone, and menthofuran, are major odor components synthesized in mint leaves. However, it is unclear how light for cultivation affects the contents of these compounds. Artificial lighting using light-emitting diodes (LEDs) for plant cultivation has the advantage of preferential wavelength control. Here, we monitored monoterpene contents in hydroponically cultivated Japanese mint leaves under blue, red, or far-red wavelengths of LED light supplements. Volatile cyclic monoterpenes, pulegone, menthone, menthol, and menthofuran were quantified using the head-space solid phase microextraction method. As a result, all light wavelengths promoted the biosynthesis of the compounds. Remarkably, two weeks of blue-light supplement increased all compounds: pulegone (362% increase compared to the control), menthofuran (285%), menthone (223%), and menthol (389%). Red light slightly promoted pulegone (256%), menthofuran (178%), and menthol (197%). Interestingly, the accumulation of menthone (229%) or menthofuran (339%) was observed with far-red light treatment. The quantification of glandular trichomes density revealed that no increase under light supplement was confirmed. Blue light treatment even suppressed the glandular trichome formation. No promotion of photosynthesis was observed by pulse-amplitude-modulation (PAM) fluorometry. The present result indicates that light supplements directly promoted the biosynthetic pathways of cyclic monoterpenes.

scholarly journals The Preferences of Different Cultivars of Lettuce Seedlings (Lactuca sativa L.) for the Spectral Composition of Light

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1211
Author(s):  
Barbara Frąszczak ◽  
Monika Kula-Maximenko
Keyword(s):  
Chlorophyll Content ◽  
Blue Light ◽  
White Light ◽  
Leaf Shape ◽  
Red Light ◽  
Spectral Composition ◽  
Fresh Weight ◽  
Light Spectrum ◽  
Dark Green ◽  
Relative Chlorophyll Content

The spectrum of light significantly influences the growth of plants cultivated in closed systems. Five lettuce cultivars with different leaf colours were grown under white light (W, 170 μmol m−2 s−1) and under white light with the addition of red (W + R) or blue light (W + B) (230 μmol m−2 s−1). The plants were grown until they reached the seedling phase (30 days). Each cultivar reacted differently to the light spectrum applied. The red-leaved cultivar exhibited the strongest plasticity in response to the spectrum. The blue light stimulated the growth of the leaf surface in all the plants. The red light negatively influenced the length of leaves in the cultivars, but it positively affected their number in red and dark-green lettuce. It also increased the relative chlorophyll content and fresh weight gain in the cultivars containing anthocyanins. When the cultivars were grown under white light, they had longer leaves and higher value of the leaf shape index. The light-green cultivars had a greater fresh weight. Both the addition of blue and red light significantly increased the relative chlorophyll content in the dark-green cultivar. The spectrum enhanced with blue light had positive influence on most of the parameters under analysis in butter lettuce cultivars. These cultivars were also characterised by the highest absorbance of blue light.

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