Optinen kirkkaus. Filensiini ja fakiniini. Mykiön kerroksista

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2358922/

In the normal rat lens, the filensin rod domain and phakinin localized to the membrane lining region in shallow cortex cells and to the central region of the cytoplasm in deep cortex cells. These results are in agreement with previous studies of the mouse lens [29]. In cells of the deep cortex, the filensin tail domain localized to subcellular membranes, but the filensin rod domain did not. As beaded filaments are composed of both filensin and phakinin, the polymerized form of beaded filaments should localize to subcellular membranes in the shallow cortex and to the central region of lens fiber cells in the deep cortex.

 The physiologic significance of the transition from membrane lining regions to the central region of the fiber cell during fiber cell differentiation is unknown.  

It is possible that the beaded filament is necessary for the formation of adhesion structures in young elongated fiber cells or that the structure that underlies the fiber cell membrane may be necessary for beaded filament polymerization in the shallow cortex of the lens. 

Polymerized beaded filaments separate from the cell membrane and localize to the center of fiber cells where they may play an important role in the maintenance of lens transparency. In the deep cortex of pre-cataract SCR lenses, filensin and phakinin were distributed throughout the cytoplasm. This result indicates that filensin and phakinin are not incorporated into beaded filaments in the deep cortex of pre-cataract SCR lenses and that polymerized beaded filaments in deep cortex cells are important for lens transparency.

The 50 kDa form of filensin was markedly decreased in pre-cataract and cataract lenses, and the localization of filensin was disordered in the deep cortex of pre-cataract lenses. These results indicate that the 50 kDa form of filensin is important for the polymerization of beaded filaments and lens transparency. The 38 kDa form of filensin was detected at very low levels in the lens cortices of young animals, which indicates that the 38 kDa form of filensin is not required for beaded filament polymerization. In conclusion, we have shown that polymerized beaded filaments are important for lens transparency and that the 50 kDa form of filensin may be a critical component of beaded filaments.

KUVA mykiön kerroksista 

 http://www.molvis.org/molvis/v11/a107/ghosh-fig4.html
Katsokaapas tätä: Linssin mykiön säleikkö on kuin jokin magneettikenttä tässä kuvassa.
 http://rstb.royalsocietypublishing.org/content/366/1568/1204/F1.large.jpg