CSB331H1 Lecture Notes - Lecture 14: Inverted Microscope, Chordin, Platelet-Derived Growth Factor
Document Summary
Early amphibian development- continued from the lecture 13 notes. Verbatim from developmental biology, 7th ed, gilbert s, sinauer, chapter 10 (with some minor modifications and information unrelated to the lecture removed) During gastrulation in xenopus, internalization of the mesoderm and endoderm occurs simultaneously. Mesoderm internalization occurs by involution; whereas endoderm internalization is promoted in part by rotation of the endoderm cells and association with the migrating mesoderm. As illustrated by a slide focused on epiboly, mesoderm involution begins dorsally, spreading laterally and ventrally to form a ring-like blastopore enveloping the yolk plug. Once internalized, the mesoendoderm (a combination of mesoderm and endodermal cells at the leading edge) moves as a coherent unit towards the animal pole, using the blastocoel roof (bcr) as a migratory surface. Fibronectin is expressed early during embryonic development, however, it precise biological functions were until recently unknown.