PURPOSE To examine the expression of maf-1 and maf-2 protocogenes in the developing rat lens. METHODS Maf-1 and maf-2 transcripts were assayed in rat lenses on embryonic days 13 and 16 (E13 and E16) by in situ hybridization using single-stranded RNA probes. Proteins encoded by the maf-2 gene were assayed immunocytochemically in embryonic (E12, 13, 16, 19) and postnatal day 14 and 90 (P14 and ...

PURPOSE Insulin and insulin-like growth factors (IGFs) are putative regulators of cell proliferation and differentiation during lens development. Transgenic mice that overexpress IGF-1 in the lens have been previously described. To further understand the ocular functions of this growth factor family, the in vivo effects of insulin expression on lens development were investigated using transgeni...

PURPOSE To map changes in the structure and function of fiber cell gap junctions that occur with lens differentiation. METHODS Equatorial lens sections were fluorescently labeled with antibodies to the gap junction protein connexin (Cx)46, the membrane marker wheat germ agglutinin, and the nuclear stain propidium iodide. Two-photon microscopy and digital image analysis were used to quantify l...

Sip1, a Smad-binding zinc-finger homeodomain transcription factor, has essential functions in embryonic development, but its role in individual tissues and the significance of its interaction with Smad proteins have not been fully characterized. In the lens lineage, Sip1 expression is activated after lens placode induction, and as the lens develops, the expression is localized in the lens epith...

PURPOSE To analyze the dynamics of N- and B-cadherin cell adhesion molecule expression and cytoskeletal interaction during embryonic chick lens development. METHODS Localization of N- and B-cadherin, F-actin, and connexin 56 were determined by immunohistochemistry of developing lenses or immunocytochemistry of differentiating primary lens cultures. Biochemical analysis of cytoskeletal linkage...

Tumor suppressor proteins are believed to play a role in regulating cell cycle control during mammalian development. The E6 and E7 oncoproteins from human papillomavirus type 16 are known to affect cell growth control, at least in part, through their inactivation of cellular tumor suppressor gene products, p53 and Rb, respectively. Therefore, these viral proteins can serve as trans-dominant rep...

PURPOSE Exposure of organ-cultured lenses to Cl(-) channel blockers under isotonic conditions induces a localized cortical zone of extracellular space dilations. The purpose of this study was to investigate whether elongated lens fiber cells from this zone contain an anion conductance that mediates Cl(-) influx and whether two chloride channel isoforms known to be expressed in the lens (ClC-2 a...

Recently, the use of stem cells has expanded into numerous areas including cell therapy. In this study, we investigated the differentiation capacity of human Wharton's jelly stem cells (hWJSCs) into lens fiber cells. Morphological changes and expressions of four crystallin genes (αA, αB, βB1 and βB3) were studied. The bovine vitreous body has been shown to induce expression of crystallin genes ...

Aldose reductase (AR) is implicated in the development of sugar cataracts by its reduction of galactose or glucose to polyols. The authors' recent work suggested that AR mRNA is found to be expressed in high concentrations in rat-lens epithelial cells after exposure of the animal to a diet containing 50% galactose. They localized the AR mRNA in the lens cells by in situ hybridization with a pre...

Lens epithelial cells communicate with two different cell types. They communicate with other epithelial cells via gap junctions on their lateral membranes, and with fiber cells via junctions on their apices. We tested independently these two routes of cell-cell communication to determine if treatment with a 90% CO2-equilibrated medium caused a decrease in junctional permeability; the transfer o...