Apoptosis induced by vitamin A signaling is crucial for connecting the ureters to the bladder.
Removal of toxic substances from the blood depends on patent connections between the kidney, ureters and bladder that are established when the ureter is transposed from its original insertion site in the male genital tract to the bladder. This transposition is thought to occur as the trigone forms from the common nephric duct and incorporates into the bladder. Here we re-examine this model in the context of normal and abnormal development. We show that the common nephric duct does not differentiate into the trigone but instead undergoes apoptosis, a crucial step for ureter transposition controlled by vitamin A-induced signals from the primitive bladder. Ureter abnormalities occur in 1-2% of the human population and can cause obstruction and end-stage renal disease. These studies provide an explanation for ureter defects underlying some forms of obstruction in humans and redefine the current model of ureter maturation.
Batourina
Ekatherina
E
Columbia University, Department of Urology, 650 West 168th Street, New York, New York 10032, USA.
Tsai
Sheaumei
S
Lambert
Sarah
S
Sprenkle
Preston
P
Viana
Renata
R
Dutta
Sonia
S
Hensle
Terry
T
Wang
Fengwei
F
Niederreither
Karen
K
McMahon
Andrew P
AP
Carroll
Thomas J
TJ
Mendelsohn
Cathy L
CL
D000818:Animals; D017209:Apoptosis; D018398:Homeodomain Proteins / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D009399:Nephrons / Q000166:cytology / Q000196:embryology*; D038081:Organogenesis / Q000235:genetics; D015398:Signal Transduction; D014513:Ureter / Q000196:embryology*; D001743:Urinary Bladder / Q000196:embryology*; D014801:Vitamin A / Q000502:physiology*
D018398:Homeodomain Proteins; C093253:Hoxb7 protein, mouse; D014801:Vitamin A