The primary goal of this project is to characterize the ocular zonule biochemically, ultrastructurally and immunologically, to provide tools for investigating diseases of this basic unit in the elastic tissue system. The glycoprotein composing the zonular fibers will be isolated and characterized in bovine and human eyes, to better define zonular microfibrillar protein. Polyclonal and monoclonal antibodies made to these purified proteins will be used in tissues for investigating abnormalities of the zonule and the ocular elastic tissues. These diseases result in zonular breakage and dislocation of the lens, but are frequently associated with disorders of ocular growth, especially myopia, and so have a broader significance. The dermal elastic system will also be studied in these diseases, as well as in the pseudo-exfoliative syndrome to determine whether the changes in the elastic micro- brillar system are generalized. The structural organization of the zonular fiber and its components will be studied by rotary shadowing and by immuno-electron microscopy using zonular and matrix antibodies. The cells involved in zonular fibrillogenesis will be investigated in fetal rabbit and bovine eyes by immunochemistry, and evidence sought for zonular receptors on the ciliary and lens epithelial cell surfaces. Adhesion proteins mediating zonular-basement membrane attachment will also be investigated immunologically. In collaborative work, zonular antibodies will be used to obtain cDNAs for sequencing zonular protein and for developing specific zonular probes.