Lecture 23

Question 1

Reciprocal interactions between which two structures are responsible for the induction of the definitive kidney

Answer 1

Ureteric bud and metanephric mesenchyme

Question 2

Which structure involved in the interactions that form the definitive kidney is derived from a small outpocketing of intermediate mesoderm

Answer 2

Ureteric bud

Question 3

Which structure of the early developing kidney will give rise to the calyces

Answer 3

Ureteric bud

Question 4

Which structure of the early developing kidney will form the definitive nephric tubules

Answer 4

Metanephric mesenchyme

Question 5

Explain how the reciprocal inductive interactions of the 2 structures that form the definitive kidney lead to the formation of the renal vesicles

Answer 5

The ureteric bud induces the nephrogenic mesenchyme to condense around the bud and undergo a mesenchymal-to-epithelial (MET) cell transition to form the renal epithelium and later, the renal vesicles

Question 6

What type of cell transition does the metanephric mesenchyme undergo to form the renal vesicles

Answer 6

Mesenchymal to epithelial cell transition

Question 7

The renal vesicles grow and differentiate to form the nephrons of the kidney. Describe the different events occurring proximally and distally

Answer 7

The proximal regions of the renal vesicles will fuse with the ureteric bud whereas the distal regions will develop into the Bowman’s capsule and attract the blood endothelium that form the glomerulus

Question 8

The distal convoluted tubule develops most distally to the uretic bud whereas the proximal convoluted tubule develops most proximally, T or F

Answer 8

F – in fact, this is vice versa, the anatomical terms were coined before understanding the development of the nephron

Question 9

Put these stages of nephrogenesis in order. A - comma-shaped body, B - nephron, C - S-shaped body, D - Metanephric mesenchyme

Answer 9

d, a, c, b

Question 10

Nephrons arise from pretubular aggregates, a subpopulation of the cap mesenchyme, in response to which signal

Answer 10

Wnt9b

Question 11

What 3 genes are early molecular markers of pretubular aggregates

Answer 11

Pax8, FGF8 and Wnt4

Question 12

Which two signals are responsible for causing the conversion of the pretubular aggregates into epithelial vesicles

Answer 12

Lhx1 and wnt4

Question 13

Which transcription factor does the renal vesicle then display a polarised expression of in presumptive distal nephron precursors

Answer 13

Brn1/Pou3f3

Question 14

Which proximal nephrons fates is notch2 signalling necessary for the specification of

Answer 14

Podocytes and the proximal tubule

Question 15

Which cells invade the proximal cleft of the S-shaped body

Answer 15

Angioblasts that later contribute to the glomerulus

Question 16

What happens at the distal portion of the S-shaped body

Answer 16

It fuses with the collecting duct

Question 17

What process does the ureteric bud undergo to form the millions of renal vesicles required to form the nephrons of the mature kidney and which genes are likely to play a role in this

Answer 17

Branching morphogenesis – under the unfluence of FGF, sprouty and BMPs

Question 18

Which structure induces the branching of the ureteric bud

Answer 18

Metanephric mesenchyme

Question 19

Hox7b is a gene normally expressed by the cells of the ureteric bud, as it is a transcription factor, what sort of experimental evidence proves this

Answer 19

Transgene created with GFP marker under the control of the Hox7b promoter