test 2 lecture 13 urogenital 1 Flashcards
BMP4 gradients set up 4 divisions of mesoderm:
paraxial
intermediate mesoderm
chorda mesoderm- notochord
lateral mesoderm
urogenital system is made of __ and is derived form __
urinary and genital system
intermediate mesoderm
The intermediate mesoderm is specified by ___ transcription factors whose expression is required to form the kidney.
homeodomain
three stages of kidney development
pronephros
mesonephros
metanephros
why did cutting the embryo prevent kidney from forming
intermediate mesoderm needs to be connected to paraxial mesoderm to receive the correct signals and form a kidney
pronephros
transient 1st stage of kidney formation
most cranial
Wolffian duct/ nephric duct induces adjacent mesenchyme to form tubules of pronephros
__ induces adjacent mesenchyme to form tubules of pronephros
anterior nephric duct/wolffian duct
Mesonephros
forms as pronephros starts to degrade
very long forms mesonephric duct
will eventually degrade when last stage (metanephros) starts
the mesonephros tube will form the ___ at one side and __ at the other side
bowmann’s capsule
mesonephric duct (future male development)
the __ develop alongside the mesonephros
gonad
paramesopnephric duct
future female development
also called the mullerian duct
another name for paramesonephric duct
mullerian duct
Metanephros
last stage of kidney
metanephrogenic meschenchyme is attached to the ureteric bud
metanephrogenic meschenchyme is attached to the ___
ureteric bud
Metanephros turns into
: ureter, renal pelvis, clayces, collecting tubules
collecting ducts develop from ___
ureteric bud
how do Ureteric bud invades the metanephrogenic mesenchyme (blastema) interact
metanephric tissue caps condense into
renal vesicles which elongate and attach to collecting tubes formed by ureteric buds
renal vesicles will continue to grow and loop to form bowman’s capsule and surround the golmerulus
urerteric buds branch into ___
major calyx and then branch even more to form minor calyx and collecting tubes
factors that control kidney
Mesenchyme will produce WT1 which will allow tissue to respond to BMP7 and FGF2 produced by ureteric bud, this induces mesenchyme to make vesicles by proliferation and maintaining WT1 expression
WT1 regulates GDNF and HGF production by mesenchyme
this process is controlled by MET mesechyme-epithelial transition: PAX2 promotes condensation, WNT4 causes meschenchyme to epithelialize and form tubules
Ureteric bud growth is dependent on ___and its receptor __
GDNF -made by metanephrogenic mesenchyme
Ret- receptors on ureteric bud
how does budding of ureteric bud happen
GDNF is secreted by metanephrogenic mesenchyme, these bind to Ret receptors on ureteric bud and stimulate growth
Ret receptors on tips of ureteric buds and keep dividing/budding
Lim1 (Lhx1)
Lim1 is expressed in a dynamic pattern throughout urinary system development: intermediate mesoderm, nephric duct, mesonephric tubules, ureteric bud, pretubular aggregates & their derivatives.
Lim1 is transiently expressed in mesenchyme (when primary vesicles formed)
Lim1 is continuously expressed in ureteric bud & derivatives
Lim1 null mice die at E10 because they lack ___. The nephric duct never forms properly (preventing induction of ___)
metanephros.
metanephros
Lim1 functions in distinct tissue compartments of the developing metanephros:
- for both proper development of the ureteric buds & patterning of renal vesicles for nephron formation.
Pax2 and Pax8 are expressed in ___ stage
pronephros
Pax2 and Pax8 are necessary & sufficient to specify the ___ lineage
nephric
•Pax2 null embryos still form mesonephric duct which degrades, thus it cannot interact with ___
metanephric mesenchyme
•Pax2 null embryos lack metanephros & genital tract
•Pax2 null embryos lack ___
metanephros & genital tract
•Pax8 null embryos still develop ___ because ___
kidneys
redundancies of Pax Family
Pax2/5/8 family members have similar functions & can substitute for each other during development
•Pax2/8 null embryos cannot form ___
pronephros or mesonephros
•Pax2/8 null embryos unable to initiate mesenchymal epithelial transition and do not express __
Lim1
genetic markers needed for development of Anterior IM
Lim1
yellow part
genetic markers needed for development of wolffian duct
Lim1
Pax2/8
genetic markers needed for development of Ureteric bud
Gata3
Lim1
Pax2/8
Wnt9B
Ret
BMP7
FGF2/9
Wnt6
genetic markers needed for development of metanephric mescenchyme
WT1
lim1
Pax2/8
genetic markers needed for development of cap mesenchyme, pretubular aggregate and renal vesicle
WT1
genetic markers needed for development of cap mesenchyme
WT1 and GDNF
genetic markers needed for development of pre tubular aggregate and renal vesicle
Wnt4
lim1
WT1
Pax2/8
during development kidneys move ___ and gonads move __
up
down
XY
male
ZZ
male bird
ZW
female bird
ZZ
male bird
Insects: ratio of X to autosomes determines sex. ___ has no role
Y
XX female
XY or X male
Grasshoppers: ___females and ___ males
XX
XO
primary sex deterimination
is Y chromosome then male
secondary sex deterimination
hormones produced by gonads influence physiological phenotype outside the gonads
SRY gene= male (sorry your a boy)
activated Sox9 and induces testis formation
is SYR present then __ form, if SYR is absent then __ form
testes
ovaries: female sex organs
___ induce gonadal development
PGC
primordial germ cells
PGC enter genital ridge, form primitive sex cords that can become male or female
when PGCs enter the genital ridge they form the ___
primitive sex cords (indifferent gonad)
week 8 testes development
mesonephric duct degrading, rete testis cords forming and growing to make testis cords, outer membrane tunica albuginea forming
week 16 testes development
testis cords have formed horseshoe shape and are connected to rete testis cords which is connected to the excretory mesonephric tubules (ductuli efferentes) which is connected to the mesonephric duct (ductus deferens)
the testis cords are made of: PGCs, sertoli cells and leydig cells (testosterone)
the testis cords are made of:
PGCs, sertoli cells and leydig cells (testosterone)
ovary development week 7
mesonephric tubule degrading
medullary cords degrade
surface epithelium thickens
PGCs dissociate into cell clusters in the medulla and form cortical cords
ovary development week 20
2nd generation of cortical cord invading the mesenchyme
mesonephric tubule becomes ductuli efferentes which leads to mesonephric duct
clusters of PGCs become primary oocytes, follicular cells develop
2 pairs of genital ducts
mesonephric
in females medullary cords degrade
in males testes cords connect to rete testis connect to mesonephric duct
paramesonephric
Mullerian duct in females
transcription factors for sexual dimorphism
transcription factors for males
SRY → Sox9→ SF1 and other genes → testes
Sox 9 inhibits WNT4 the female transcription factor
Female Transcription factors
WNT4→ DAX1 and other genes(TAFII 105) → ovaries
DAX1 inhibits SOX9
Metanephrogenic mesenchyme causes the ___ to elongate and branch
ureteric bud
explain metanephric tissue caps
Tissue caps make WT1 (transcription factor), this gets mesenchyme ready to bind (makes competent) to FGF2 and BMP7 (growth factors) from ureteric bud,
this stimulates mesenchyme proliferation (make renal vesicles by MET which is induced by PAX2 and WNT4 that is produced by the ureteric bud) and maintain WT1 expression
WT1 also regulates GDNF ( used to bind and branch ureteric bud) and HGF
excretory units comes from
metanephric mesenchyme
collecting system comes from
ureteric bud
The intermediate mesoderm is specified by ___ whose expression is required to form the kidney.
homeodomain transcription factors
3 homeodomain transcription factors necessary for intermediate mesoderm to form the ___
Pax2, Pax8, and Lim1
kidney
The intermediate mesoderm acquires its ability to form the kidneys through its interactions with the ___
paraxial mesoderm.
___ have overlapping boundaries in the frog, and kidney development starts with cells that express both genes.
Pax8 and Lim1
Ectopic co-expression of Pax8 & Lim1 will make ___ in other tissues.
kidneys
If Pax2 is experimentally expressed in the presomitic mesoderm, it converts that paraxial mesoderm into ___, expresses Lim1 and forms kidneys.
intermediate mesoderm
In mouse embryos, knockout of ___ genes, the mesenchyme-to-epithelium transition needed to form the kidney duct fails, and the cells undergo apoptosis, and no nephric structures form.
Pax2 and Pax8
Pax2 and Lim1 induce ___ of each other in the mouse.
expression
Lim1 is necessary for converting intermediate mesenchyme into ___
kidney duct.
Lim1 is also required for forming ___ in mesonephric and metanephric mesenchyme.
ureteric bud & tubular structure
___ is the earliest stage of kidney formation that forms cranially in the nephrogenic plate.
Pronephros
The pronephros has 7-8 pairs of ___ that develop at the level of somites 7-14.
pronephric tubules
The pronephros persists in ___. In ____, the pronephros regresses.
fish and lower vertebrates
mammals
___ is the second stage of kidney development
Mesonephros
Each tubule in the mesonephros is associated with a blood vessel on the cranial end and attaches to the ___ on the posterior end.
pronephric duct
The mesonephric duct extends to the cloaca and will persist in ___.
males
pronephric duct grows caudally to the cloaca and becomes the ___.
mesonephric duct (Wolffian duct)
mesonephric tubules grow and form an S-shaped loop that are associated with a tuft of capillaries called a ___ medially which will form the Bowman’s capsule. These structures form a ___.
glomerulus
renal corpuscle
The mesonephros persists in ___. The mesonephros degenerates rapidly in ___. But the mesonephric duct will persist in ___.
amphibians
mammals
males
__ is the third stage of renal development and becomes the kidney in reptiles, birds and mammals.
Metanephros
The ___ branches from the mesonephric duct and interacts with the surrounding mesenchyme.
Ureteric bud
Metanephros or permanent kidney develops ___ to the mesonephros.
caudal
___ cells condense around the terminal buds of the branching ureteric bud and develop into a renal tubule.
Mesenchymal blastema/ metanephrogenic mesenchyme
Precursors of vascular endothelial cells migrate into the vicinity of metanephric blastema/ metanephrogenic mesenchyme and form capillaries that will form the ___ and connect to the aorta.
glomerulus
A basal lamina forms between the developing tubules and the glomerular endothelial cells which later will be the ___
renal filtration barrier
In the metanephros, the comma-shaped tubule becomes S-shaped and then elongates to form a hairpin shaped ___
loop of Henle.
The metanephros is derived from:
- *Ureteric bud** – outgrowth of mesonephric duct
- *Metanephric blastema/ mesenchyme**– mesoderm located at the caudal endo of the nephrogenic cord
Functional nephrons develop from 3 cell types:
- Epithelial cells from the ureteric bud
- Mesenchymal cells from the metanephric blastema
- Endothelial cells of the developing capillaries
Outgrowth of the ureteric bud from the mesonephric duct is a response to the secretion of ___ by the undifferentiated mesenchyme of the metanephrogenic blastema.
glial cell line–derived neurotrophic factor
(GDNF )
GDNF is bound by ___, a member of the tyrosine kinase receptor superfamily, which is located in the plasma membranes of the epithelial cells of the early ureteric bud.
cRet
The formation of GDNF in the metanephric mesenchyme is regulated by ___
WT-1
___ signaling in the surrounding mesoderm is also inhibitory to outgrowth of the ureteric bud, but within the metanephrogenic blastema its action is counteracted by the___ , which is produced within the blastema itself.
Bone morphogenetic protein (BMP)
BMP-inhibitory actions of gremlin
these two types of mesenchyme, ___ and ___, create a sharp border between the forming ureter (associated with ___mesenchyme) and the intrarenal collecting duct system (associated with ___ mesoderm).
intermediate mesoderm and tailbud mesenchyme
tailbud
intermediate
the ____ of the adult kidney shares properties with the ureter and the collecting system, and its cellular origins are unclear.
renal pelvis
The morphological foundations for the development of the metanephric kidney are the elongation and branching (up to 14 or 15 times) of the ureteric bud, which becomes the ___ system of the metanephros, and the formation of renal tubules from mesenchymal condensations (metanephrogenic blastema) located around the tips of the branches.
collecting (metanephric) duct