Educational content related to optogenetics-Neurobiology
"Manipulation of various neural circuits and the effect on behavior in Drosophila using optogenetics: NGSS-Neurons, genetics, and selective stimulations "
The purpose of this web page is to provide information for ongoing outreach projects with researchers, science teachers in middle and high schools as well as the general public.
We are designing educational modules for middle and high school teachers. The teachers can then use material as needed for their educational units.
Too often life science is distilled into disparate facts addressing major biological concepts, but lacking purpose for learning and applying knowledge to real world contexts. The driving principle of this project is to build learning modules employing real world scenarios to foster authentic scientific investigation in biological sciences.
Content addressed in modules aligns with the Next Generation Science Standards (Achieve, Inc., 2013) for middle and secondary life science, Engineering Design, and Science and Engineering Practices, and promotes critical thinking skills in biological science.
Resources: Papers and web links
NEUROPHYSIOLOGY TEXT BOOK ON LINE (use for a review of basic concepts)
Free background information on neurobiology neuron morphology, conducting electrical, ionic bases of resting & action potential, and synapse structure
Background reading in optogenetics and fly behaviors:
Majeed Z, Koch F, Morgan J et al. A novel educational module to teach neural circuits for college and high school students: NGSS-neurons, genetics, and selective stimulations F1000Research 2017, 6:117 (doi: 10.12688/f1000research.10632.1) https://f1000research.com/articles/6-117/v1
Lights and Larvae: Using optogenetics to teach recombinant DNA and neurobiology. The Science Teacher 81 (#6):2-9. [PDF].
Optogenetics in the teaching laboratory: [PDF]
Optogenetic manipulation of neural circuits and behavior in Drosophila larvae [PDF]
Channelrhodopsin reveals experience-dependent influences on courtship [PDF]
Selective neural activity in multiple freely moving Drosophila adults [PDF]
Nature 2015- review on optogenetics [PDF]
Nature 2015- review on optogenetics- commentary [PDF]
Nature 2015- review on optogenetics- neuroscience [PDF]
Optopharmacological tools for restoring visual function in degenerative retinal diseases (link to abstract)
Top 10 discoveries in 10 years of optogenetics (link to)
Ion channels with ChR channels (PDF)
Background information for teaching about altering neural activity in these excercises:
Regulation in activating inhibitory and excitatory neurons while monitoring effects on acute and chronic behaviors emphasis the importance of these neural circuits. To do this type of manipulation within in an organism which is easy to rear and maintain is ideal for hands on inquiry based learning for high school and college courses which emphasize life science topics. This teaching module is designed to integrate modern genetics, engineering, physics, life sciences, modeling and experimental design. Researching the primary scientific literature and the utilizing the related findings as well as postulating the outcome for newly designed experiments based on the results one collects, the students can test their own predictions and draw hypotheses. This approach provides autonomous learning within and among student groups. The measureable outcomes with obtaining quantitative data for analysis and interpretation is a valuable learning experience. Based on ones findings in the initial experiments one can readily redesign experimental paradigms to test the formulated hypotheses utilizing ones own prior data. The integration with Arduino hardware and software opens the doors for students to a world of writing code with an experimental purpose and independence in experimental design.
The underlying science in these modules focuses on neurobiology. The seminal discoveries by Hubel and Wiesel (1970) demonstrated that activity in sensory input and within the CNS is key in the development and maintenance of neural circuits. This concept is also important for development and maintained synaptic establishment at neuromuscular junction (NMJ) of skeletal muscles (Balice-Gordon et al., 1990; Lomo, 2003). In some cases, the activity profile must occur prior to developmental time points to have plasticity before the neural circuits become more hardwired. After the critical period in synaptic formation, the circuit is not as dependent on activity for competition with other neurons for the establishment of connections. This fundamental phenomenon occurs in organisms from fruit flies to humans. It is known in mice that even after established connections are made as adults that the terminals at NMJs are not fixed to on spot on the muscle fiber. The motor nerve terminals grow out and pull back over time while continuing to communicate with the muscle (Lichtman and Sanes, 2003)
If motor neurons which are normally innervating a muscle are removed than other motor neurons will take control of the target and innervate. Thus, motor nerves are searching out targets not all ready committed by other synaptic inputs (Chang and Keshishian, 1996). This was examined in embryonic and larval Drosophila by laser ablating various skeletal muscle fibers during development. Even pharmacological activating or silencing neural circuits during development can have long term consequences in neural connections and overall physiological functions (Smith et al., 2015). For example exposing rodents to nicotine during development changes the dendritic morphology within the CNS which lasts into adulthood (McDonald et al., 2005). Even short exposures in the juvenile stages have long lasting effects in adults for these mice (Ehlinger et al., 2015). Thus, long term consequences in the established neural circuitry within the CNS and at the NMJ can occur based on neural activity when the initial circuits are being formed.
A guided self-inquiry based approach to learning science has been demonstrated to being a very effective means for student learning over the long term (Bradforth, et al., 2015; Waldrop 2015). The engineering design with the Arduino systems is a very engaging educational experience sought after in many schools within the USA and abroad. Students can design the experiments with various computer codes to control the duration of light on-off time period and frequency of stimulation to observe how activating or inhibiting specific set on neurons alter development and behavior of the Drosophila larvae or adults.
The hardware for the Arduino and associated LED required hardware is relatively inexpensive <$20 USD for an individual unit; however, making a series of units with one power supply is cheaper for adding additional units. Class sets can be used in subsequent years so an initial investment has a long term use. There are dozens of demonstration videos on YouTube for a wide variety of inventions and coding using Arduino.
In this educational module, we demonstrate and approach with optogenetics to selectively activate the neurons synthesizing the neurotransmitter GABA, glutamate, serotonin, and acetylcholine. The approach used to stimulate these selective neurons is to activate light sensitive channels expressed in these neurons. Different Drosophila lines will be used for each type of neurotransmitter. The ability to control the stimulation with light is to be managed by Arduino system the students can program. The surge in the use of the Arduino system in high school and college teaching is partly due to the low cost and ease in writing code for operating the system.
The participants can readily add single units or build parallel outputs with discrete parameters for controlling the LEDs. Thus, this allows various parameters to be tested simultaneously in the same laboratory setting. Since many of the experimental paradigms will be novel and many unanswered questions remain to be answered in neurobiology, students may uncover unique findings worthy of publication in scientific journals.
This educational module is also designed to embrace the Next Generation Science Standards (NGSS Lead States, 2013) through approaches scientists employ in the development of scientific knowledge. The participants for this exercise will be able to construct models in the neural circuits to explain the observed behavioral phenomenon to make sense of what they observe. The direct real life examples with how neural circuits develop in ones self as well as in other animals is of general interest but also has applied implications for medicine and health. The ability to manipulate various neurotransmitter systems and stimulation paradigms promotes experimental design and redesign based on the observed findings from each experiment. This is an integral aspect of the NGSS. This approach promotes explanations of the findings in order to set a new or altered stimulation paradigm as they continue to study a phenomenon in different contexts. NGSS recommends that models be used in Developing, Evaluating, Using, and Revising explanations and predictions of science phenomena
Interesting side articles and links related to this topic
Anatomical and genotype-specific mechanosensory responses in Drosophila melanogaster larvae. Neuroscience Research 83:54-63 [PDF]
Optogenetics (MS word, PDF)
Table of which lines activate which type of neurons (PDF, MS Word )
Recording of an Introduction to the lab: used for Bio 350 (animal physiology, Univ. of KY)
dowload (movie here 123 MB) (power point only here)
Sample movies of larval behavior: (these are large movies so need to download 1st and then open). Hot linked so click on title.
OK371-ChR2 minus ATR third instar-L1
OK371-ChR2 plus ATR third instar-L1b
UAS-ChR2-XXL x Gad1-GAL4 minus ATR
UAS-ChR2-XXL x Gad1-GAL4 plus ATR
UAS-ChR2-XXL x Gad1-GAL4 plus ATR contracted-photo
UAS-ChR2-XXL x Gad1-GAL4 plus ATR relaxed-photo
Type IV sensory neurons:
UAS-ChR2-XXL x ppk-GAL4 third instar-1
5-HT containing neurons:
UAS-ChR2-XXL x Trh-GAL4 minus ATR
UAS-ChR2-XXL x Trh-GAL4 plus ATR3
Participants designing this content are :
Zana Majeed*#, Felicitas Koch%, Joshua Morgan^, Robin L. Cooper*
* Dept. Biology & Center for Muscle Biology, Univ. KY. Lexington, KY. USA;
# Dept. Biol., Univ. Salahaddin, Erbil, Iraq;
% V.M.F., Univ. Leipzig, Leipzig, Germany;
^ Dept. Electrical Engineering, Univ. KY. Lexington, KY. USA.
ZRM supported by Higher Committee for Education Development (HCED) scholarship in Iraq. FK supported by Deutscher Akademischer Austausch Dienst (DAAD) German Academic Exchange Service. RISE - Program (Research Internships in Science and Engineering). Personal funds supplied by RLC.
maintained by Robin L. Cooper. Contact: RLCOOP1 at UKY.EDU