I have finished the set of slides I was imaging! For the rest of the week I will be working on getting training and certification in order to work with the mice. The lab is going to be doing many behavioral tests on the mice in about four weeks, and I will be staying past the end of the senior project to help with that.
I put copies of the left hemisphere of two different mice brains that I imaged. The top one has lots of labeling (it looks like little green dots), which means it is probably a normal mouse that was sleep deprived, while the bottom one has no labeling, which means it is probably one of the knock out mice. I know the image is not very clear, but if you look closely on the original image you can see axons/dendrites coming off of the green dots of the neurons.
___________________________________________
Happy Friday!
I am got to run a gel again today for DNA testing. I attached a picture of the results below. The lab manager trained me on how to tell the genotypes based on the banding. Basically, the top band is only present if the mouse has the knockout trait (no functional Egr3 gene), the second band shows if the mouse has the Egr3 gene, the third band shows if the mouse has the X chromosome (they all do), and the fourth band shows if the mouse has a Y chromosome.
Just as a recap of Mendelian genetics, if the mouse has the knockout and normal Egr3 bands it means they are a heterozygote (written as +/-) and if they only have the knockout trait (-/-) or only have the normal wild type trait (+/+) they are homozygous. If the mouse has the trait, they will have a band at the first, second, third, or fourth place, and if they don't have the trait there won't be a band there.
The genotypes of the first row from left to right are: Male +/+, Male -/-, Female +/-, Female -/-, Female +/+, Male +/-, Male +/-, Male +/-, Male +/-, Female +/-
I am also still doing the training to earn all the certifications needed to work in the vivarium (the room with the mice). It is a long process to get certified! I still have one more online training to do and I need to fill out a form about the vaccinations I have gotten and any allergies I have, so the lab can determine if it is safe for me to work with the mice.
In a few weeks, probably around week 10 of my senior project, the lab is planning to do behavioral tests on the mice, and I will be helping with that. I am also going to continue volunteering at the lab over the summer.
Wow, that's so awesome to hear that your internship/volunteering will expand beyond your senior project! It just goes to show the great influence these projects can have on your interests. In addition to that, the fact that you'll soon be able to work with the mice is just as fantastic news!! I also very much enjoyed the pictures. When you say work with mice and help perform behavioral tests, what kind of tests are these? Happy Friday!
ReplyDeleteI will have more information about the tests later on, when I am given more training. I do know that the tests will be similar to past tests the lab has conducted on the mice, such as a Y maze test (mice are placed in a maze with three branches and it is recorded how often they explore a new branch of the maze rather than going back to the branch they came from), and a locating cookie test (a cookie is hidden under the bedding of the mouse cage and it is timed how long it takes the mouse to find the cookie). I don't know exactly which tests they will be conducting, but I will post that when I know!
DeleteHi Serena! It sounds like you're having a lot of fun at your project site! And I'm also impressed (like Kiri) that you would be willing to carry your research over in the summer; very admirable. I was wondering, what do the green dots in the brain represent? And also what is the next thing you thin you'll do for your project?
ReplyDeleteThank you and keep up the great work!
The green dots are neurons that have Egr3 active, so they are allowing Htr2 to produce serotonin receptors. We see these green dots in the normal mice but not the knockout mice, which have no Egr3 and few serotonin receptors.
DeleteHey Serena! I was wondering if you knew the reason that the MRIs come out different for the different kinds of mice? Good luck with your training and certification and everything!
ReplyDeleteThese are not MRIs. I am imaging slides using a microscope with a camera attached, and a special light to make the cells fluoresce green. They are different for different kinds of mice because the wild type mice have the Egr3 gene while the knockouts mice do not express the Egr3 gene.
DeleteHey Serena!
ReplyDeleteIt's amazing that you had a fun and eventful week! I find it so inspiring that you are continuing your research throughout the summer. What do the different green dots mean on each of the pictures? Also, what behaviora patterns will you be researching with and how can they be analyzied through the neuroimaging?
I'm so excited to keep reading!
Julie Loison-10
The green dots show where serotonin 2A receptors are being made in the brain. These are made when the gene Egr3 is activated by stress, because Egr3 regulates the gene that makes serotonin receptors. In the Egr3 knockout mice, there are no green dots (second picture) but the normal mice that are sleep deprived have green dots (second picture).
DeleteThe behavior study that I will be helping out with is not related to the imaging, but it will be using the same mice types. The mice are injected with a virus that changes their DNA so they produce more serotonin 2A receptors, and behavioral tests will be conducted to see if this reduces the behavioral problems the knockout mice have.
Hi Serena! I really enjoyed seeing the pictures you had uploaded of the mice brains! It seems like your project is really coming along! Was there a particular reason for only examining the left hemisphere of the brain! I'm really enjoying reading your blog; can't wait for next week!
ReplyDeleteSophia Vaidya
I imaged both hemispheres, but I made a separate image of both to make it easier for the people counting the green dots. I just happened to choose left hemisphere pictures to put on the blog.
DeleteHey Serena! Your dedication to your project is really inspiring! I was just curious as to how you could tell that the mouse was normal but sleep deprived by looking at the labeling or green dots? Keep up the great work and good luck!
ReplyDeleteNormal mice that are sleep deprived have lots of green dots. Normal mice that are not sleep deprived only have a few green dots. Knockout mice (without Egr3) have no green dots.
Delete