gastrulation in xenopus and zebrafish

Question 1

What is gastrulation?

Answer 1

The phase of morphogenetic movements in early development that brings about the formation of the three germ layers

Question 2

3 germ layers?

Answer 2

Endoderm mesoderm ectoderm

Question 3

What does the endoderm give rise to?

Answer 3

Lungs, thyrous, digestive cells

Question 4

What does the mesoderm give rise to?

Answer 4

Cardiac muscle, skeletal muscle, smooth muscle, RBCs

Question 5

What does the ectoderm give rise to?

Answer 5

Skin, neurons, pigment cells

Question 6

Order of layers of the germ layers (in to out)?

Answer 6

Endo, meso, ecto

Question 7

Purpose of gastrulation?

Answer 7

Generate body plan
Establish anterior and posterior axis
Place the germ layers in their correct position

Question 8

What does neurulation follow?

Answer 8

Gastrulation

Question 9

What happens in neuralation?

Answer 9

Formation of the neural plate

Question 10

Two mechanisms of gastrulation?

Answer 10

Cellular mechanisms and molecular mechanisms

Question 11

Structure at blastula stage?

Answer 11

ball of cells w/ cavity (blastocoel)

Question 12

What appears as we enter gastrulation?

Answer 12

Blastopore

Question 13

What is the first physical indication of the dorsal side of the embryo?

Answer 13

blastopore

Question 14

What happens after the blastopore appears?

Answer 14

The mesodermal cells move into the blastopore and migrate inside the embryo

Question 15

Which processes are involved in blastopore formation?

Answer 15

Involution and invagination

Question 16

How is the archenteron formed?

Answer 16

Endoderm cells move into the mass via the ventrlal lip, creating a cavity

Question 17

What does the archenteron end up being?

Answer 17

Gut tube

Question 18

What are the ectoderm cells doing during gastrulation?

Answer 18

Undergoing epiboly, then convergent extension

Question 19

Role of ectoderm cells in gastrulation and neuralation?

Answer 19

Elongate the axis of the embryo

Question 20

What does fate mapping allow?

Answer 20

Origins of tissues

Question 21

How does fate mapping work?

Answer 21

Following development of cells through development and then see where their progeny end up later on in development

Question 22

How is a cell fate mapped?

Answer 22

Tagged w/ smthn and look to see where the tag is expressed in the organism

Question 23

What are the four main families of secreted proteins involved in germ later specification and patterning in xenopus?

Answer 23

Wnts, FGFs, BMPs, Nodals

Question 24

Wnt active?

Answer 24

Beta catenin isnt degraded so it enters the nucleus and activates TFs

Question 25

Why is B-catenin no degraded when nt is active?

Answer 25

Wnt recruits dishevelled and proteins from the beta catenin destruction complex to the plasma membrane

Question 26

WHat does FGF bind to?

Answer 26

Tyrosine kinase recpor

Question 27

Result of FGF binding to an RTK?

Answer 27

Receptor is phosphorylated, leading to RAS/RAF activation

Question 28

Result of RAS/RAF activation?

Answer 28

Cascade of phosphorylation events w/ MAPKinase--> MAPKinase becomes phosphorylated

Question 29

Result of MAPKinase being phosphorylated?

Answer 29

Translocates to the nucleus where it can activate TFs