Anatomy of Development

Question 1

morphogenesis

Answer 1

separation of cells as distinct entities.

Question 2

which cell types can interconvert?

Answer 2

early epithelial and mesenchyme

Question 3

cadherins can be

Answer 3

stabilizers of groups of cells, defining the population

Question 4

Hans Driesch

Answer 4

dissociated cells give rise to whole embryos

Question 5

Spemann and Mangold

Answer 5

dorsal blastopore, siamese twin. Transplant material made original material form the twin

Question 6

permissive induction

Answer 6

required to allow participant to continue what it would have become anyway

Question 7

instructive induction

Answer 7

causes cells to choose among many fates

Question 8

morphogen

Answer 8

induces along a gradient, imposing different identities

Question 9

relay signal

Answer 9

one signal makes another signal

Question 10

Shh release

Answer 10

autocatalytic cleavage of N-terminal SHH, which is given a cholesterol moiety and palmated

Question 11

Shh action

Answer 11

binds and inhibits Patch1

Question 12

Ptch1

Answer 12

a repressor receptor which inhibits Smo

Question 13

Smo

Answer 13

transmembrane protein, => Gli 1,2,3

Question 14

without SSH, Gli2

Answer 14

is degraded and Gli3 is a repressor (cleaved form)

Question 15

in the presence of SSH

Answer 15

uncleaved Gli3 is an activator! Gli 2 is not degraded, activators Gli1 transcription

Question 16

Is SHH signalling dose dependent?

Answer 16

yes

Question 17

activating mutations in SHH

Answer 17

Ptch inactivation of Smo mutant, results in basal cell cancers, medullablastoma

Question 18

SHH mutations cause midline errors such as

Answer 18

cyclopia, holoprosencephaly, cleft palate

Question 19

TGFbeta or BMP

Answer 19

dimers are serine/threonine kinases. Transphosphorylate, then phosphorylate to activate SMADs and coSMADS

Question 20

SMADs and coSMADs

Answer 20

enter nucleus and regulate target genes

Question 21

Wnt coreceptors

Answer 21

Frizzled, Lrp5/6

Question 22

Wnt reception recruits

Answer 22

Axin-DSH, GSK3, APC complex

Question 23

Axin-DSH, GSK3, APC complex prevents

Answer 23

Beta-catenin degradation

Question 24

What does beta-catenin do in the the nucleus

Answer 24

complexes w/TCF/LEF transcription factors already bound to chromatin, turns them into activators.

Question 25

FGFs interact with

Answer 25

heparin sulfate prteopglycans and TK receptors called FGFR 1-4

Question 26

FGFs activate

Answer 26

RAS-Raf-Mek-Mapk=> Erk via serine/thronine crossphos cascade

Question 27

FGF is an on/off signal because

Answer 27

the cascade activates so rapidly

Question 28

Notch-delta, long range or short?

Answer 28

short

Question 29

Notch-delta activated

Answer 29

ligand includes delta, causes notch receptor cleavage.

Question 30

Notch fragment binds ____ then goes ____

Answer 30

Cbf1 cofactor, to nucleus to regulate target (including Hes genes)

Question 31

regulation typical of notch-delta?

Answer 31

negative feedback

Question 32

retinoic acid

Answer 32

retinol is made by cell, converted to soluble acid, enters nucleus and binds Tfs, converting them to activators

Question 33

retinoic acid receptors

Answer 33

RARs dimerized with RTRs

Question 34

EphrinA, B ligands bind

Answer 34

Eph receptors

Question 35

Ephrin signalling is special because

Answer 35

both ligands and receptors can act as receptors.

Question 36

Ephrin signal function

Answer 36

changes cytoskeleton proteins in eph+ cells

Question 37

inhibitors of BMP

Answer 37

i.e., chordin. Bind BMP and associated complex with glypican membrane-tethered protein to limit its mobility outside of cell

Question 38

Tolloid

Answer 38

proteases cleave chordin, causing rerelease of BMP

Question 39

homeotic genes

Answer 39

cahnge identiy of tissue (e.g., legs in the wrong place)

Question 40

E-cadherins bind

Answer 40

E-caherins

Question 41

N-cadherins bind

Answer 41

N-cadherins

Question 42

totipotent

Answer 42

can generate all tissues of the embryo, including extraembryonic

Question 43

pluripotent

Answer 43

can form all germ layers, but not extraembryonic

Question 44

C-Kit receptor mutation

Answer 44

white patches on head and chest

Question 45

thalidomide

Answer 45

change in limb growth without genetic lesion

Question 46

fetal alcohol

Answer 46

change in head shape, etc.