BSCI430 Exam III - Mesoderm

What are the four major subdivisions of mesoderm?

Chordamesoderm, Paraxial mesoderm, Intermediate mesoderm, Lateral plate mesoderm

What are the derivatives of chordamesoderm?

Notochord, which signals surrounding tissues and contributes to axis formation

What structures are derived from paraxial mesoderm?

Head mesoderm, somites (which give rise to sclerotome, myotome, dermatome)

What are the two components of lateral plate mesoderm and their fates?

Splanchnic mesoderm (forms heart, blood vessels, gut connective tissue); Somatic mesoderm (forms body wall, limbs)

What role does BMP play in mesodermal patterning?

High BMP specifies lateral plate; intermediate BMP specifies intermediate mesoderm; low BMP specifies paraxial mesoderm

What transcription factors are involved in paraxial mesoderm specification?

Fgf8, Wnt3a, Retinoic acid, Tbx6, Msgn1, Cyp26b

What is the mesenchymal to epithelial transition (MET) in somitogenesis?

A process where mesenchymal cells in presomitic mesoderm transition into epithelial somites

Which genes regulate MET in somitogenesis?

Mesp, Eph, Ephrin

What is the clock-wavefront model of somitogenesis?

Somite formation depends on oscillating Notch signaling and a wavefront of Fgf8 gradient

What are the three main compartments of a somite and what do they become?

Sclerotome (vertebrae), Myotome (skeletal muscle), Dermatome (dermis of back)

What are the stages of kidney development from intermediate mesoderm?

Pronephros, Mesonephros, Metanephros

What transcription factors are involved in intermediate mesoderm and kidney specification?

Lim1, Pax2, Pax8

What is the role of the ureteric bud?

It induces metanephric mesenchyme to form the definitive kidney

What does the coelom become?

The body cavity separating visceral and parietal mesodermal layers

What genes are important for cardiogenic mesoderm and heart development?

BMP, Fgf8, Nkx2-5, Mesp1, BMP antagonists, Wnt inhibition

What is vasculogenesis?

Formation of blood vessels from mesoderm-derived hemangioblasts

What is angiogenesis?

Sprouting and branching of new blood vessels from existing ones

What factors specify hemangioblasts?

BMP, Wnt, Notch, Fgf2, VEGF