Drosophila larver er lysfølsomme og reagerer på ændringer i det omgivende lys. Denne video beskriver en analyse, der tester deres evne til at undgå lys, kaldet lysplet assay. Den fremhævede protokol demonstrerer, hvordan man opsætter analysen med en blå lys LED og viser, hvordan man registrerer dyrets adfærd som reaktion på lysmødet.
Protocol
Denne protokoltekst er et uddrag fra Sun et al., Light Spot-Based Assay til analyse af Drosophila Larval Phototaxis, J. Vis. Exp. (2019). 1. Opsætning af billedbehandlingssystemet Klem et webkamera med høj opløsning med et strygeclips, ca. 10 cm over lyspletten på skrivebordet (Figur 1). Juster kameralinsens retning mod skrivebordet. kameraet til en computer via en USB-grænseflade. Placer en agarplade …
Representative Results
Figur 1: Eksperimentel opsætning. (A) Skematisk repræsentation af opsætningen for den lyse plet-baserede larve hurtig phototaxis assay. De blå linjer repræsenterer stierne for synligt lys, der bruges som visuel stimulering, og de røde linjer repræsenterer stierne for infrarødt lys. Pile angiver lysets retning. 850 nm båndpasfilteret gør det muligt for infrarødt lys at passere, men det blokerer …
Materials
850 nm ± 3 nm infrared-light-generating LED
Thorlabs, USA
PM100A
Compatible Sensors: Photodiode and Thermal
Optical Power Rangea: 100 pW to 200 W
Available Sensor Wavelength Rangea: 185 nm-25 μm Display Refresh Rate: 20 Hz
Bandwidth: DC-100 kHz
Photodiode Sensor Rangeb: 50 nA-5 mA
Thermopile Sensor Rangeb: 1 mV-1 V
LED Current Range: 0-2 A
LED Current Resolution: 1 mA
LED Current Accuracy: ±20 mA
LED Forward Voltage: 24 V
Modulation Frequency Range: 0-100 kHz Sine Wave
Modulation: Arbitrary
Collimated LED blue light
ELP, China
USBFHD01M
Max. Resolution: 1920×1080
F6.0 mm
Sensor: 1/2.7" CMOS OV2710
Compact power meter console
Ocean Optics, USA
USB2000+(RAD)
Dimensions: 89.1 mm x 63.3 mm x 34.4 mm
Weight: 190 g
Detector: Sony ILX511B (2048-element linear silicon CCD array)
Wavelength range: 200-850 nm
Integration time: 1 ms – 65 seconds (20 seconds typical)
Dynamic range: 8.5 x 10^7 (system); 1300:1 for a single acquisition
Signal-to-noise ratio: 250:1 (full signal)
Dark noise: 50 RMS counts
Grating: 2 (250 – 800 nm)
Slit: SLIT-50
Detector collection lens: L2
Order-sorting: OFLV-200-850
Optical resolution: ~2.0 nm FWHM
Stray light: <0.05% at 600 nm; <0.10% at 435 nm
Fiber optic connector: SMA 905 to 0.22 numerical aperture single-strand fiber
High-Power LED Driver
Minhongshi, China
MHS-48XY
Working voltage: DC12V
Central wavelength: 850nm
high-resolution web camera
Thorlabs, USA
MWWHL4
Color: Warm White
Correlated Color Temperature: 3000 K
Test Current for Typical LED Power: 1000 mA
Maximum Current (CW): 1000 mA
Bandwidth (FWHM): N/A
Electrical Power: 3000 mW
Viewing Angle (Full Angle): 120°
Emitter Size: 1 mm x 1 mm
Typical Lifetime: >50 000 h
Operating Temperature (Non-Condensing): 0 to 40 °C
Storage Temperature: -40 to 70 °C
Risk Groupa: RG1 – Low Risk Group
LED Warm White
Mega-9, China
BP850/22K
Ø25.4(+0~-0.1) mm
Bandwidth: 22±3nm
Peak transmittance:80%
Central wavelength: 850nm±3nm
Spectrometer
Noel Danjou
Amcap9.22
AMCap is a still and video capture application with advanced preview and recording features. It is a Desktop application designed for computers running Windows 7 SP1 or later. Most Video-for-Windowsand DirectShow-compatible devices are supported whether they are cheap webcams or advanced video capture cards.
Standard photodiode power sensor
Super Dragon, China
YGY-122000
Input: AC 100-240V~50/60Hz 0.8A
Output: DC 12V 2A
Thermal power sensor
Thorlabs, USA
M470L3-C1
Color: Blue
Nominal Wavelengtha: 470 nm
Bandwidth (FWHM): 25 nm
Maximum Current (CW): 1000 mA
Forward Voltage: 3.2 V
Electrical Power (Max): 3200 mW
Emitter Size: 1 mm x 1 mm
Typical Lifetime: 100 000 h
Operating Temperature (Non-Condensing): 0 to 40 °C
Storage Temperature: -40 to 70 °C
Risk Groupb: RG2 – Moderate Risk Group
Thermal power sensor
Thorlabs, USA
S401C
Wavelength range: 190 nm-20 μm
Optical power range:10 μW-1 W(3 Wb)
Input aperture size: Ø10 mm
Active detector area: 10 mm x 10 mm
Max optical power density: 500 W/cm2 (Avg.)
Linearity: ±0.5%