Wnt/β-catenin signalling in the developing kidney is critical for ureteric bud branching morphogenesis. A mutation blocking Wnt9b specifically disrupts:
- A Induction of metanephric mesenchyme to undergo mesenchymal-to-epithelial transition (MET) ✓
- B Formation of the ureteric bud from the mesonephric duct
- C Glomerulogenesis via podocyte differentiation
- D Migration of renal progenitors from the intermediate mesoderm
Correct answer: A. Induction of metanephric mesenchyme to undergo mesenchymal-to-epithelial transition (MET)
Explanation
Wnt9b secreted from the ureteric bud epithelium signals to the surrounding metanephric mesenchyme, inducing the mesenchymal-to-epithelial transition (MET) that converts loose mesenchyme into the renal vesicle — the precursor of the nephron. Ureteric bud outgrowth from the mesonephric duct is driven by GDNF–RET signalling. Glomerulogenesis requires WT1 and VEGF from podocytes. Intermediate mesoderm specification involves Pax2/8.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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