Lecture 1 - Molecular Genetics of Salivary Gland Development

Question 1

Three Fundamental Processes of Salivary Gland Organogenesis

Answer 1

Positional Information, Morphogenesis, Differentiation

Question 2

Assembly of Multicellular salivary glands involved what four changes

Answer 2

Shape Changes - Invagination
Cell Migration - Using extension to move
Axis Elongation - Using convergent extension, which cells build up and then collapse into one line
Changes in Tissue Gene expression

Question 3

Branching Morphogenesis of Salivary Gland (Initiation)

Answer 3

Reciprocal Signaling result in repetitive clefting, and new bud formation and branching

Question 4

The processes involved in progenitor cell maintence

Answer 4

Proliferation
Lineage Commitment
Differentiation

Question 5

Importance of FGF in Salivary Gland Formation

Answer 5

Inhibition results in lose of branching

Overexpression results in overbranching

Question 6

Cell Types Differentiated Into

Answer 6

Myoepithelial, Epithelial, Mesenchymal, Neuronal, Endothelial

Question 7

Fibronectin Importance

Answer 7

Accumulates in location of cleft formation and therefore branching
Expresses in epithelial deposiited in mesenchym

Question 8

Acinar and Ductal Cell differentiation

Answer 8

Acinar - from outer buds (signaled from basement membrane)
Ductal - from inner cell buds
Both seen v early in morphogenesis

Question 9

ZO-1 Function In Salivary Gland Formation

Answer 9

Distributed to apical domain (opposite of the lumen) in cells reorganizing into ducts
Makes domain in the cell
It sets up polarity

Question 10

F-Actin Function in Salivary Gland Formation

Answer 10

Works with ZO-1 to elongate ductal Axis for duct extension into the newly forming buds.

Question 11

Parasympathetics in Salivary Gland Formation

Answer 11

innervation regulates tubulogenesis

A loss will decrease maintenance of K5 progenitor

Question 12

E-Cadherin Importance for Salivary Gland formation

Answer 12

Cell-cell adhesion molecule, required for survival of differentiating ductal cells and maintenance
E-Cadherins are a tumor suppresoe
With a problem with E Cahderins you get abnormal lumen and duct formation (Larger)

Question 13

Hippo Signaling Pathway (purpose and result of mutation)

Answer 13

interacts with E-Cadherin cell cell adhesion receptor to drive normal duct formation
Deforming pathway leads to huge growth
importance in maintain size, polarity and shape of duct

Question 14

Lats 1/2 Importance

Answer 14

Conserved in all eukaryotes, allows for phosphorylation of TAZ and YAP
Without Lats they dont get phosphorylated so excess growth

Question 15

TAZ and YAP Function

Answer 15

When phosphorylated cell goes toward morphogenesis (shaping)
When they are not phosphorylated then there is growth and replication
If inhibit Lat lose shape and branching

Question 16

Sjogren Patient Risk Factors

Answer 16

Loss of Cell Polarity
E Cadherin Junction problems
YAP nuclear localization
Salivary function will be problematic

Question 17

Sjogrens Syndrome

Answer 17

Autoimmune disease with decrease salivary flow, because glands are infiltrated with T lymphocytes