Prox1 function is crucial for mouse lens-fibre elongation

Nat Genet. 1999 Mar;21(3):318-22. doi: 10.1038/6844.


Although insights have emerged regarding genes controlling the early stages of eye formation, little is known about lens-fibre differentiation and elongation. The expression pattern of the Prox1 homeobox gene suggests it has a role in a variety of embryonic tissues, including lens. To analyse the requirement for Prox1 during mammalian development, we inactivated the locus in mice. Homozygous Prox1-null mice die at mid-gestation from multiple developmental defects; here we describe the specific effect on lens development. Prox1 inactivation causes abnormal cellular proliferation, downregulated expression of the cell-cycle inhibitors Cdkn1b (also known as p27KIP1) and Cdkn1c (also known as p57KIP2), misexpression of E-cadherin and inappropriate apoptosis. Consequently, mutant lens cells fail to polarize and elongate properly, resulting in a hollow lens. Our data provide evidence that the progression of terminal fibre differentiation and elongation is dependent on Prox1 activity during lens development.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Bromodeoxyuridine / analysis
  • Bromodeoxyuridine / metabolism
  • Cell Cycle Proteins*
  • Cell Differentiation / genetics
  • Cell Division / genetics
  • Crystallins / genetics
  • Cyclin-Dependent Kinase Inhibitor p27
  • Embryonic Induction / genetics
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Gene Expression Regulation, Developmental*
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / physiology
  • Immunohistochemistry
  • Lens, Crystalline / abnormalities
  • Lens, Crystalline / cytology*
  • Lens, Crystalline / embryology*
  • Mice
  • Mice, Mutant Strains
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism
  • Molecular Motor Proteins
  • Mutation
  • Saccharomyces cerevisiae Proteins*
  • Tumor Suppressor Proteins*
  • beta-Galactosidase / genetics


  • Cdkn1b protein, mouse
  • Cell Cycle Proteins
  • Crystallins
  • Fungal Proteins
  • Homeodomain Proteins
  • KIP2 protein, S cerevisiae
  • Microtubule-Associated Proteins
  • Molecular Motor Proteins
  • Saccharomyces cerevisiae Proteins
  • Tumor Suppressor Proteins
  • prospero-related homeobox 1 protein
  • Cyclin-Dependent Kinase Inhibitor p27
  • beta-Galactosidase
  • Bromodeoxyuridine