TITLE:
Lens Capsule HSPG-Perlecan Regulates Lens Fibre Differentiation during Chick Embryo Development
AUTHORS:
Cristina Martín, María I. Alonso, Francisco Lamus, José A. Moro, A. De la Mano, José M. Fernandez, Alberto Caballero, Ángel Gato
KEYWORDS:
Eye Development, Lens Fibre Differentiation, HSPG-Perlecan, FGF-2, Chick Embryo
JOURNAL NAME:
Open Journal of Veterinary Medicine,
Vol.7 No.2,
February
28,
2017
ABSTRACT: Lens fibre differentiation is a life-long process
related with lens transparency, and is particularly intense during development,
being related with an FGF-2 antero-posterior gradient at the equator level as
the main growth factor involved which has been related with the basal membrane
of the lens anlagen known as “Lens capsule”. However the lens fibre differentiation induced by
FGF2 depends, as in other biological systems, on the local bioavailability of FGF-2 regulated by
their relationship with extracellular matrix molecules as Heparan Sulphate
Proteoglycans. Here, we try to clarify how Perlecan (a heparan sulphate proteoglycan specific from basement membranes) is
involved in lens fibre differentiation at earliest stages of eye
development. Our results show that Perlecan, is a major component in the lens capsule during the earliest
stages of lens development in chick embryos being present during lens plate
induction, lens vesicle stage and the onset of lens fibre differentiation. In
order to demonstrate a direct involvement of HSPG-Perlecan in lens fibre differentiation, we generate depleted lenses by
HSPG-Perlecan synthesis disruption and specific enzymatic digestion. The
HSPG-Perlecan depleted lens show a significant delay or abolition in the lens
fibre differentiation which remains in an immature cells displaying
DNA synthesis in the posterior epithelium and a decrease in FGF2 lens expression.
These data support the hypothesis that lens capsule HSPG-Perlecan is a
key molecule involved in lens fibre differentiation during development,
probably by involvement in FGF-2 biodisponibility.