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QUIZ #2B INSTRUCTIONS **Be sure to read the FAQs on the Announcements if you have not already done so** Quiz #2B, which is really just a take-home assignment, is meant to help prepare you for the final exam and know what my expectations are regarding the level of detail required to obtain full marks. There are 2 questions in this assignment. Read the instructions for each question carefully before answering. The assignment will be graded out of 15 marks and is worth 5% of your grade in the course. Due Date: You must submit Quiz #2B to me directly in class on Friday, November 4th. Submissions after the in-class deadline will be counted as late, and a penalty of 10% per day will be incurred for students submitting their assignment after the deadline. Students who submit Quiz #2B late must email them directly to me (
[email protected]). **If you are sick on Friday, November 4th and can’t come to class then you can email Quiz #2B to me before 12:30pm (when class begins). ***Make sure to clearly indicate your name and student number on the first page.*** Good luck! 1. Data interpretation and figure design (total of 5 marks) The Abstract below describes a study that integrates several ideas covered in NUTR*3360 to date. Note that this Abstract is made up by me and not a real study (so you won’t find this abstract online). You will notice that there are 8 spots in the abstract that are highlighted. Based on this highlighted text, you will need to create 5 figures that reflect the Abstract results. You must create 5 figures that correspond to 5 of the 8 blanks. All figures must show all experimental groups. Note that you do not need to indicate units (numbers) in the axes, but axes do need to have titles. You also need to clearly indicate what is “increased/higher”, what is “reduced/lower”, or what is the “similar/same” in your figures using symbols. There are more than 5 figures that can be made based on the results outlined in this Abstract and you are free to choose what figures you want to include in your assignment. ******************************************* ABSTRACT: The endocannabinoid system (ECS) is known to regulate whole-body energy homeostasis. The objective of this study was to determine if the metabolic changes associated with ECS signaling arise, in part, via changes in gut bacteria. To accomplish this goal, researchers fed wild-type (WT) and CB1-/- (knock-out) adult mice a high omega-6 diet for 3 months. Additionally, a separate group of wild-type mice were fed the same omega-6 diet but also received rimonabant (WT+R) throughout the 3-month feeding study. WT mice fed the omega-6 diet had higher body weight during the 3-month feeding trial compared to CB1-/- and WT+R mice, which weighed the same. Hypothalamic levels of anandamide and 2-AG in WT mice were similar compared to CB1-/- and WT+R mice. Various blood markers, such as leptin, insulin, and glucose were higher in WT mice compared to CB1-/- and WT+R mice. Food intake was similar between WT, CB1-/- and WT+R mice. Fecal energy content was lower in WT mice compared to the other two groups. SSU 16S rRNA analysis of fecal samples revealed that WT mice had higher Firmicutes and lower Bacteriodetes compared to CB1-/- and WT+R mice. Butyrate and propionate levels in the cecum were higher in WT mice compared to CB1-/- and WT+R mice. Analysis of liver lipid metabolism showed that WT mice had increased lipogenic gene expression compared to CB1-/- and WT+R mice, which was reflected in hepatic triglyceride levels. Collectively, this study demonstrated that a diet rich in n-6 PUFA promotes endocannabinoid signaling via the central CB1 receptor to influence energy homeostasis. 2. Answer both Parts A and B (total of 10 marks) A. Using a diagram, indicate the location and role of key genes involved in the leptin-melanocortin pathway, and how they are regulated. Be sure to include how this pathway influences energy balance (i.e., energy intake vs. energy expenditure). (6 marks) B. If a young child with early onset obesity came to a health clinic, a doctor may suspect a mutation in one of the key genes in the leptin-melanocortin pathway. List the clinical clues associated with each of the 4 genes (LEP, LEPRb, POMC, and PC-1) that would help a doctor identify which gene is mutated? (4 marks) 2