The metanephrogenic blastema or metanephric blastema (or metanephric mesenchyme, or metanephric mesoderm) is one of the two
embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...
logical structures that give rise to the
kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...
, the other being the
ureteric bud
The ureteric bud, also known as the metanephric diverticulum, is a protrusion from the mesonephric duct during the development of the urinary and reproductive organs. It later develops into a conduit for urine drainage from the kidneys, which, in c ...
.
The metanephric blastema mostly develops into
nephrons
The nephron is the minute or microscopic structural and functional unit of the kidney. It is composed of a renal corpuscle and a renal tubule. The renal corpuscle consists of a tuft of capillaries called a glomerulus and a cup-shaped structure ca ...
, but can also form parts of the
collecting duct system
The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis. The collecting duct system is the last part of nephron and participates in elect ...
.
The system of tissue induction between the ureteric bud and the metanephric blastema is a reciprocal control system. GDNF,
glial cell-derived neurotrophic factor, is produced by the metanephric blastema and is essential in binding to the
Ret receptor on the ureteric bud, which bifurcates and coalesces as a result to form the
renal pelvis
The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the ureter in the kidney. It is formed by the covnvergence of the major calyces, acting as a funnel for urine flowing from the major calyces to the ureter. It has a mucous ...
, major and minor
calyces and collecting ducts. Mutations in the ''
EYA1
Eyes absent homolog 1 is a protein that in humans is encoded by the ''EYA1'' gene.
This gene encodes a member of the eyes absent (EYA) subfamily of proteins. The encoded protein may play a role in the developing kidney, branchial arches, eye, an ...
'' gene, whose product regulates ''GDNF'' expression in the developing kidney,
lead to the renal abnormalities of BOR syndrome (
branchio-oto-renal syndrome
Branchio-oto-renal syndrome (BOR) is an autosomal dominant genetic disorder involving the kidneys, ears, and neck. It often has also been described as Melnick-Fraser syndrome.
Signs and symptoms
The signs and symptoms of branchio-oto-renal syndrom ...
).
See also
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Mesenchyme
Mesenchyme () is a type of loosely organized animal embryonic connective tissue of undifferentiated cells that give rise to most tissues, such as skin, blood or bone. The interactions between mesenchyme and epithelium help to form nearly every o ...
*
Metanephros Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system. This article covers a 3 part developmental process that is observed in most reptiles, birds and mammals, including humans. N ...
*
Blastema
A blastema (Greek ''βλάστημα'', "offspring") is a mass of cells capable of growth and regeneration into organs or body parts. The changing definition of the word "blastema" has been reviewed by Holland (2021). A broad survey of how blast ...
*
Kidney development Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system. This article covers a 3 part developmental process that is observed in most reptiles, birds and mammals, including humans. N ...
References
External links
*
*
Diagram at mcgill.ca 1*
{{Authority control
Embryology