BBio 351 – November 5, 2015 Today’s outline Finish reproduction! Finish slides from Making a person: from zygote to gastrula Early embryogenesis The 2 nd week of life Hasuwa (2013): MiR-200b and miR-429 Function in Mouse Ovulation and Are Essential for Female Fertility

Making a person: from zygote to gastrula POGIL-style activity taken from Anatomy & Physiology: A Guided Inquiry by Patrick J.P. Brown Work through questions in teams… …then face “challenge questions”!

Sherwood Figure Model 1: early embryogenesis

1. Once the oocyte joins with a sperm, the new diploid cell has a new name (not listed in the figure). What is this term? a. What is the name of the process that produces this cell? 2. Within the first 2 days, the diploid cell divides twice. How many cells will there be after 2 rounds of division? a. What do you think the term “cleavage” means here? 3. What is the embryo called once it has become a solid ball of 16 or more cells? 4. On Day 5, the early blastocyst hatches. From what structure does it hatch (i.e., what does the blastocyst emerge from)? Patrick J.P. Brown Model 1 questions

5. What is the name of the single layer of cells that completely surrounds the blastocyst? a. What other component of the blastocyst is labeled? b. The blastocoel is NOT labeled. Look up what “coel” means, then label the blastocoel in the figure. 6. The early blastocyst forms at about Day 5. What major event takes place between Day 5 and Day 7? a. In what case would this major event NOT take place? Patrick J.P. Brown Model 1 questions

Challenge question(s)

Model 2: the 2 nd week of life Patrick J.P. Brown

Model 2 questions 8. According to the model, what structure grows from the trophoblast into the surrounding uterine (endometrial) tissue? a. What cavity is beginning to open up between the trophoblast and the inner cell mass at this time? 9. By Day 11, there are 2 spaces inside the embryo: 1 cavity and 1 sac. List them. a. In addition to the formation of these two cavities, another important event occurs during gastrulation. List the 3 germ layers that are formed during gastrulation and an example of a body tissue derived from each layer. b. What does gastrulation mean? Patrick J.P. Brown

Model 2 questions 10. All of the body’s tissues and organs derive from these 3 germ layers. What structure in the early blastocyst gave rise to these 3 germ layers? a. Do the trophoblast, amnion, or yolk sac appear to develop into any tissues that will be found in the child at birth? b. Why are these called extraembryonic tissues? 11. Cardiac and renal defects often occur together in newborns, as do skin and nervous disorders. As a group, explain why these (and other) birth defects often occur together. Patrick J.P. Brown

Challenge question(s)

Reproduction paper: H. Hasuwa et al., Science 2013 Review: hypothalamic-pituitary-gonadal axis How exactly does GnRH promote LH secretion? Review: control of gene expression

What are microRNAs (miRNAs)? Stefanie S. Jeffrey, Nature Biotechnology 2008

Genetic tools/tricks: reporter assay to see how miR-200b & miR-429 affect Zeb1 expression Hasuwa et al. (2013), Figure S13

Genetic tools/tricks: Zeb overexpression Google Images search results; Hasuwa et al. (2013), Figure 3B-C

Reproduction paper: H. Hasuwa et al., Science 2013 Fig. 1. Infertility phenotype of miR-DKO mice. Fig. 2. Pituitary defects in miR-DKO female mice. Fig. 3. Lhb expression is regulated by ZEB1 as a potential target of miR-200b and miR-429.

Fig. 1. Infertility phenotype of miR-DKO mice. Hasuwa et al. (2013), Figure 1A

Fig. 1. Infertility phenotype of miR-DKO mice. Hasuwa et al. (2013), Figure 1C-F

Fig. 2. Pituitary defects in miR-DKO mice. Hasuwa et al. (2013), Figure 2A-D

Fig. 2. Pituitary defects in miR-DKO mice. Hasuwa et al. (2013), Figure 2E-H

Fig. 3. Lhb expression is regulated by ZEB1 as a potential target of miR-200b and miR-429. Hasuwa et al. (2013), Figure 3D-E

Diagram to summarize main findings?

What questions could be researched next?