Development Of The Musculoskeletal System Flashcards
Chondrocytes are coded for by which key gene?
Sox9.
Osteoblasts are coded for by which key gene?
Runx2.
By which process do all skeletal elements, except cranial vault and majority of facial bones, form?
Endochondral ossification.
A mutation in Sox9 causes which disease?
Campomelic dysplasia.
A mutation in Runx2 causes which disease?
Cleidocranial dysplasia.
Somites are formed from which type of mesoderm?
Paraxial mesoderm.
Which 2 signalling pathways are involved in the somite segmentation clock?
Notch and WNT.
What kind of polarity do somites have?
Rostrocaudal.
What happens during resegmentation of the somites?
Sclerotome will split along the midline and fuse with the adjacent sclerotome.
1 somite gives rise to how many vertebrae?
1.
Which protein expressed on the somites ensures that the pattern of the ventral roots is established?
Ephrin.
How many sets of hox genes are there in vertebrates?
4.
Which part of the mesoderm forms the sternum, limbs and pelvic girdle?
Lateral plate mesoderm.
Changes in which signalling pathway cause vertebral malformations?
Notch.
Name the 5 stages of development of skeletal elements?
- Condensation.
- Matrix production.
- Differentiation (cartilage zones established).
- Vascularisation and bone collar formation.
- After birth secondary growth centre formation.
What are BMPs required for?
Skeletal and cartilage development.
Name a BMP antagonist?
Noggin.
What does excess BMP lead to?
Synostosis.
What do mutations in Noggin lead to?
Multiple synostosis syndrome.
Achondroplasia comes about as a result of mutations in which receptor?
FGF3.
What is acromegaly?
Excess growth after epiphyseal plate closure.
Which disease is characterised by ossification of muscles provoked by injury?
Fibrodysplasia ossificans progressiva (FOP).
How can vascular smooth muscle cells become calcified?
Excess BMPs or decrease in BMP antagonists.
Osteoclasts are coded for by which key gene?
RANKL.
