Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 233.6 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 267.2 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 267.2 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Deprecated: Implicit conversion from float 267.2 to int loses precision in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 534
Warning: imagejpeg(C:\Inetpub\vhosts\kidney.de\httpdocs\phplern\27144443
.jpg): Failed to open stream: No such file or directory in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 117 PLoS+One
2016 ; 11
(5
): e0153422
Nephropedia Template TP
gab.com Text
Twit Text FOAVip
Twit Text #
English Wikipedia
Postembryonic Nephrogenesis and Persistence of Six2-Expressing Nephron Progenitor
Cells in the Reptilian Kidney
#MMPMID27144443
Camarata T
; Howard A
; Elsey RM
; Raza S
; O'Connor A
; Beatty B
; Conrad J
; Solounias N
; Chow P
; Mukta S
; Vasilyev A
PLoS One
2016[]; 11
(5
): e0153422
PMID27144443
show ga
New nephron formation (nephrogenesis) ceases in mammals around birth and is
completely absent in adults. In contrast, postembryonic nephrogenesis is well
documented in the mesonephric kidneys of fishes and amphibians. The transient
mesonephros in reptiles (including birds) and mammals is replaced by the
metanephros during embryogenesis. Thus, one may speculate that postembryonic
nephrogenesis is restricted to the mesonephric kidney. Previous reports have
suggested the metanephros of non-avian reptiles (hereafter reptiles) may
continually form nephrons throughout life. We investigated the presence of adult
nephrogenesis in reptiles by examining adult kidneys from several species
including Trachemys scripta, Chrysemys picta, Boa constrictor, Tupinambis tegu,
Anolis carolinensis, and Alligator mississipiensis among others. We found that
all major reptilian groups (Testudines, Crocodylia, and Squamates) showed the
presence of adult nephrogenesis. The total amount of nephrogenesis varied greatly
between species with turtles displaying the highest density of nephrogenesis. In
contrast, we were unable to detect adult nephrogenesis in monotremes, and in the
iguanid A. carolinensis. Nephron progenitor cells express the transcription
factor Six2, which in mammals, becomes downregulated as the progenitor cell
population is exhausted and nephrogenesis ends. Using the alligator as a model,
we were able to detect Six2-positive cap mesenchyme cells in the adult kidney,
which spatially correlated with areas of nephrogenesis. These results suggest
that the metanephric kidney of reptiles has maintained the ability to continually
grow new nephrons during postembryonic life, a process lost early in mammalian
evolution, likely due to the persistence of a Six2-expressing progenitor cell
population.