MM Embryology 1 Flashcards
1
Q
eventual identity of the cell
A
cell fate
2
Q
population of daughter cells from a single parent
A
cell lineage
3
Q
a cell’s fate is _______ if it generates a certain cell type when cultured in isolation
A
specified
4
Q
a cell’s fate is ____ if it generates a certan cell type even when exposed to abnormal influences
A
determined
5
Q
hedgehog ligands
A
SHH, IHH, DHH
6
Q
hedgehog receptor actions
A
patch binding disinhibits smoothened
7
Q
hedgehog transducer
A
smoothened activates glia
8
Q
hedgehog output
A
Gli goes to nucleus
9
Q
TGFbeta/BMP ligand
A
many TGFs/BMPs
10
Q
TGFbeta/BMP receptor action
A
serine/threonine kinases dimerize, autphosphorylate
11
Q
TGFbeta/BMP tranducer
A
Smad is phosphoylated
12
Q
TGFbeta/BMP output
A
Smad and other factors go to nucleus
13
Q
Wnt ligand
A
Many Wnts
14
Q
Wnt receptor actions
A
Frizzled and arrow binding inhibits kinase
15
Q
Wnt transducer
A
beta catenin is not degraded
16
Q
Wnt output
A
B catenin enters nucleus and promotes transcription
17
Q
FGF ligand
A
many FGFs
18
Q
FGF receptor actions
A
tyrosine kinase activation sets off phosphorylation cascade
19
Q
FGF transducer
A
MAPK pathway
20
Q
FGF output
A
Phosphorlyated Erk activates transcription
21
Q
Retinoic acid ligand
A
retinol (lipid soluble steriod)
22
Q
retinoic acid receptor action
A
retinol, metabolized to retinal in the cell
23
Q
retinoic acid transducer
A
Crabp binds retinal and transfers it to the nucleus
24
Q
retinoic acid output
A
retinal/RXR complex activated transcription
25
notch delta ligand
delta
26
notch delta receptor action
notch binding cleaves intracellular portion of notch
27
notch delta transducer
cleaved portion of notch
28
notch delta output
cleaved portion regulates transcription
29
dorsal side of bilaminar embryo
amniotic cavity
30
ventral side of bilaminar embryo
yolk sac
31
bilaminar embryo surrounded by
extraembryonic coelum
32
nervous system, skin
ectoderm
33
notocord extends from rostral end of primitive streak and induces ectoderm to thicken and become nervous system
neurulation
34
invaginates to form neural tube and closes in opposite directions starting in cervical region
ectoderm
35
neural crest cells migrate and give rise to
PNS
36
CT, bone, muscle, GU organs
mesoderm
37
develops into somites that give rise to axial skeleton, musculature, skin, dermis
paraxial mesoderm
38
GU system
intermediate mesoderm
39
interembryonic coelum develops within this, will give rise to body cavities, blood vessels and heart
lateral mesoderm
40
Gut
endoderm
41
IEC becomes continuous around
the midgut
42
combo of yolk sac and connecting stalk, lined by same cells as amniotic cavity
umbilical cord
43
delivers oxygenated blood
umbilical vein
44
returns blood to placenta
umbilical arteries
45
surrounds heart and lungs, paritions into 2 pleural and one pericardial cavity
interembryonic coelum
46
becomes foregut, midgut, and hindgut
yolk sac
47
diverts blood around liver to IVC
ductus venosus
48
hole between atriums where blood enters to bypass lungs
foramen ovale
49
shunt from pulmonary artery to aorta to bypass lungs
ductus arteriosus
50
supply the bladder for a while
umbilical arteries
51
Cdx to blastocyst
be trophectoderm!
52
Gata6 to blastocyst
be endoderm
53
Nanog to blastocyst
be epiblast
54
Hippo to blastocyst
determines inside or outside
55
Yap turns on Cdx
in outer cells (be trophectoderm!)
56
Nodal and Crypto inhibitor
Lefty
57
Wnt Inhibitor
DKK1
58
Lhx1 (from anterior visceral endoderm)
allows for neural plate formation by stimulating inhibitors of anterior-headed growth
59
blastopore, using Wnt and Nodal
Axis induction in gastrulation
60
head formation, from AVE via Lhx1
anterior posterior axis in gastrulation
61
notocord (from axial mesoderm) and neural plate via SHH
dorsal -ventral axis in gastrulation
62
cilia, nodal and lefty, Pitx2 and Islet 1
Left-rigth axis
63
somite formation takes place in the ____ week, and somites form from ______
3rd, paraxial mesoderm
64
the clock drives _____ tissue to ______ somites
mesenchymal presomitic, epithelial
65
the clock uses ______ to activate ________
delta/notch, Lfng & Hes
66
Lfng inhibits _____, and Hes downregulates _______
notch, Lfng and Hes
67
defect in notch that leads to missing vertebra
Alagille syndrome
68
Lfng mutation that leads to missing/irregular ribs
spondylocostal dysostosis
69
wavefront uses a ____ gradient from _____ to prevent somite growth
FGF/Wnt, notochord
70
wavefront signal also promotes ______ growth
Tail-end (so inhibition is pulled caudally)
71
dermatome, myotome, sclerotome, syndetome
4 somite differentiations
72
dermatome
skin.
73
myotome
spinal, body wall and limb muscle
74
sclerotome
axial skeleton but not sternum
75
segmental nerves run ____ somites, blood vessels run _____ them.
through, between
76
syndetome
tendons, between myotome and sclerotome
77
determine axial patterning of somites
Hox genes
78
Hox genes default to
rostral
79
all hox genes are homeobox, but
not all homeobox are hox
80
limbs are made of
mesoderm and ectoderm
81
mesoderm lateral plate makes what in limbs?
skeleton and tendons of limbs. (somite makes muscles)
82
ectoderm makes what in limbs?
motor innervation (spinal cord) sensory neurons (dorsal ganglia/neural crest) skin
83
mesoderm FGF10 to Ectoderm FGF8
positive feedback loop in limbs
84
limbs form when
Week 4
85
limbs rotate when
Week 6-8
86
localized FGF, FGF10-8 feedback
limb initiation
87
TBX5
forelimb coorelate
88
TBX4, Pitx1
hindlimb correlate
89
FGF and Wnt, retinoic acid flank
Proximal/Distal in limb
90
RA promotes what in limb
proximal growth in limb
91
Wnt and FGF in proximal to distal limb promotes what
distal growth in limb
92
what center controls proximal/distal in limb?
apical Ectodermal Ridge
93
what center controls anterior/posterior in limb?
zone of polarizing activity
94
what is expressed on posterior side at ZPA?
SHH
95
SHH constrains Gli, which contrains what in limb?
number of digits
96
Wnt to Lmx in limb determines what
dorsal cell fate
97
En-1 (preventing Wnt) determines what
ventral cell fate
98
AD, mut TBX5, cardiac defects
Holt Oram syndrome
99
Mut Tbx3
Ulnar-mammary syndrome
100
AD Mut LMX1B, nail diplasia, no patella, nephropathy, ocular malformation
Nail Patella syndrom
101
AR, SHH deletion in limb, lack formed distal extermities
Acheriopodia
102
Ectopic SHH exppression, many digits
Preaxial polydactyly
103
p63 mutation, reduced AER maintenance
split hand/foot malformation
104
Ectopic AER
diplopodia and eudiplodia
105
axial skeleton comes from
somitic mesoderm
106
appendicular skeleton and sternum come from
lateral mesoderm
107
craniofacial skeleton comes from
neural crest ectoderm
108
osteoclasts comes from
monocytes
109
determines location and shape of all skeletal elements
patterning
110
early skeletal patterning defects are ____, late are _____ .
lethal, local (local are called dysostoses)
111
establishes the cellular structure of the skeleton
skeleotgenesis
112
skeletogenesis defects are called _____, and are ______, not local
dysplasia, generalized
113
no RANKL so too much bone forms
osteopetrosis
114
no OPG, so too much bone loss
osteopenia
115
Runx2/Msx2 haploinsufficiency
slow fusion, gaps in skull
116
activating mutations in FGFR or Msx2, OR haploinsufficiency of Twist (neg. regulator of Runx2)
craniosynostosis (accelerated fusion)
117
Sox 9 role in skeleton
chondrocyte differentiation
118
Sox 9 knockout
lethal
119
Sox9 haplo
campomelic dysplasia
120
IHH role in skeleton
chondrocyte proliferation and maturation
121
IHH knockout and haplo
normal bones, smaller size (less proliferation in growth plate)
122
PTHrP role in skeleton
inhibits IHH, slows maturation on chondrocytes into hypertrophics
123
PTHrP knockout and haplo
normal bones, reduces size. Less severe than IHH. Jansen and Blomstrand chondrodysplasia
124
Runx role in skeleton
regulates expression of osteoblasts (turns cartilage to bone)
125
Runx knockout
lethal
126
Runx haplo
cleidocranial dysplasia (smaller or mishapen bones)
127
Atf4 role in skeleton
regulates expression of osteoblasts and AA transport, phosphorylated by Rsk2
128
Atf4 without Rsk2
inactive: Coffin-Lowry syndrome (low bone mass)
129
Atf4 overexpression
bone phenotype of neurofibromatosis 1
130
Hox role in skeleton
patterning gene cluster (segmented organization)
131
Hox knockout
messed up pattern
132
epidermis (no blood vessels) comes from
ectoderm
133
dermis comes from
mesoderm
134
keratinocytes, melanocytes, merkel cells, langerhans cells, and t cell
are all residents of epidermis
135
keratinocytes come from
ectoderm
136
melanocytes comes from
ectoderm, via dorsal neural crest
137
merkel cells comes from
ectoderm, via keratinocytes
138
langerhans cells comes from
mesoderm, via blood line
139
T-cells come from
skin! In the skin. Are not replenished from thymus
140
connective tissue, blood and nerves live in
the dermis
141
skin stem cells work
alone. Unless there is injury and healing
142
If ectoderm progenitors see Wnt
BMP is promoted, giving SKIN!
143
If ectoderm progenitors see FGF
BMP is inhibited, giving CNS!
144
ectoderm differentiation at 4 weeks
CNS or skin
145
skin differentiation at 7-21 weeks
hairy or not hairy
146
if skin sees BMP, notch +
stratified epidermis, not hairy
147
if skin sees Wnt10b
we're going down the hair pathway
148
hair follicle: wnt induces
the placode
149
hair follicle: EDA induces
Wnt10b in the placode
150
hair follicle: Shh in the placode
drives proliferation in placode
151
all cells of bud, peg and follicle come from
SHH expressing cells
152
hair follicle: Dkk1 inhibits
Wnt, to keep cells around hair from becoming hair
153
EDA defects resulting in loss of Wnt10b (affects hair, teeth and glands)
hypohidrotic ectodermal dysplasias
154
PTCH mutation, no SMO inhibition, unwanted cell proliferation
gorlin syndrome/basal cell carcinoma
155
since notch is part of stratified epidermis pathway, it is mystically involved in
squamous cell carcinoma
