Dynamin Binding Protein Is Required for Xenopus laevis Kidney Development.

Area of Science:

• Developmental Biology
• Cell Biology
• Nephrology

Background:

• The human kidney has over a million nephrons, each with specialized tubular segments for absorption and excretion.
• The embryonic Xenopus laevis kidney, a single nephron model, shares functional analogies with human nephrons, aiding nephrogenesis studies.
• The exocyst complex, involving CDC42, is vital for protein trafficking and normal kidney development.

Purpose of the Study:

• To investigate the role of dynamin binding protein (Dnmbp/Tuba), a CDC42-guanine nucleotide exchange factor, in Xenopus kidney development (nephrogenesis).

Main Methods:

• Studied Dnmbp expression in Xenopus embryos.
• Utilized morpholino antisense oligonucleotides for Dnmbp knockdown.
• Generated dnmbp knockout Xenopus embryos using CRISPR.
• Investigated the effects of Dnmbp overexpression in developing kidneys.

Main Results:

• Dnmbp knockdown reduced late pronephric markers but not early ones, with greater impact on distal/connecting tubules.
• Dnmbp reduction caused glomus and ciliary defects.
• CRISPR knockout led to similar marker reductions and embryonic edema.
• Dnmbp overexpression also disrupted pronephric tubules, indicating tight regulation is necessary.

Conclusions:

• Dynamin binding protein (Dnmbp) is essential for normal nephrogenesis in Xenopus.
• Both reduced and increased Dnmbp levels disrupt kidney development.
• Dnmbp plays a critical role in pronephric tubule development and differentiation.