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The Vertebrate Eye and Its Adaptive Radiation.

Junctional intercellular communication and the control of growth

Lens Differentiation in Vertebrates: A Review of Cellular and Molecular Features

https://www.cell.com/cell/pdf/0092-8674(84)90190-9.pdf

The major intrinsic protein (MIP) of the bovine lens fiber membrane : characterization and structure based on cDNA cloning

https://science.sciencemag.org/content/sci/197/4299/127.full.pdf

The vertebrate eye lens.

A portrait of plasma membrane specializations in eye lens epithelium and fibers.

In this paper evidence is provided that one of the protein components of the water-soluble fraction of the calf lens binds specifically to deoxyribonuclease I (DNAse I). On the basis of this property, the polypeptide could be purified by applying DNAse I affinity chromatography. Concomitantly a protein of Mr 55000 and a rather large amount of α-crystallin copurify with this polypeptide, which has a molecular weight of 42000.



Highly purified 42000-Mr protein was also obtained by extraction of the water-insoluble fraction of the calf lens with 2-{[tris(hydroxymethyl)methyl]amino}ethanesulfonic acid followed by gel filtration. Amino acid analyses, peptide mapping and electron microscopy show that the protein obtained from both lens fractions is identical to non-muscle actin. Furthermore the amino acid composition of the 55000-Mr protein is identical to hog stomach skeletin and very similar to calf brain desmin.

https://febs.onlinelibrary.wiley.com/doi/epdf/10.1111/j.1432-1033.1979.tb12995.x

Actin in mammalian lens.

Actin has been purified from varius non-muscle cells and characterized by its molecular weight and ability to polymerize into filaments. Although the occurrence of this protein has been postulated in the mammalian eye lens after observation of actin-like filaments in the electron microscope, definite (bio)chemical proof has been provided only recently. Amino acid analysis, peptide mapping and affinity chromatography revealed the identity of lens actin with the corresponding protein in other tissues. As the filaments could be obtained by co-isolation with highly purified lens plasma membranes, we were interested to know how the actin-containing structures wre located in situ. In the experimental approach reported here, the indirect immunofluorescence technique (IFT) was applied to unfixed cryostat sections of lens tissue. The distribution of actin in calf, rat and pigeon lens is described, and evidence from this for the role of actin in visual accommodation discussed.

M. A. Kibbelaar

Papers

A portrait of plasma membrane specializations in eye lens epithelium and fibers.

Actin in mammalian lens.

Is actin in eye lens a possible factor in visual accomodation

Nomenclature for the polypeptide chains of lens plasma membranes.

Fractionation of the water-insoluble proteins from calf lens