CFTR structure and function: is there a role in the kidney?

Area of Science:

• Nephrology
• Genetics
• Molecular Biology

Background:

• Cystic fibrosis (CF) is a genetic disorder caused by CF transmembrane conductance regulator (CFTR) mutations.
• CFTR is expressed in the kidney, but major renal dysfunction is not typical in CF patients.
• However, altered urinary protein excretion and urine concentrating/diluting capacity are observed in CF.

Purpose of the Study:

• To review the structure and function of CFTR.
• To elucidate the role of CFTR in renal physiology.
• To explore CFTR modulation by hormones regulating extracellular fluid volume.

Main Methods:

• Review of existing literature on CFTR in renal physiology.
• Analysis of studies on CFTR expression and function in kidney tissues.
• Examination of CFTR's role in ion transport and protein handling in nephrons.

Main Results:

• CFTR mRNA is present in all nephron segments, with higher abundance in the renal cortex and outer medulla.
• CFTR protein is detected on the apical surface of proximal and distal tubules in rat kidneys.
• CFTR transports both Cl- and ATP, potentially influencing Na+ and K+ channels and protein endocytosis.

Conclusions:

• CFTR plays a significant role in renal physiology beyond chloride transport.
• Its function in ion transport and potential involvement in protein handling are critical for kidney function.
• Understanding CFTR's renal role is essential for managing CF patients and exploring therapeutic targets.