TI - p130Cas and Akt S473 PHOSphorylation is reduced in the AND-34-/- lens epithelium . AB - AND-34/BCAR3 induces serine PHOSphorylation of p130Cas in human breast cancer epithelial cells in an adhesion -dependent manner ( unpublished observation ) . Such serine PHOSphorylation results in reduced p130Cas PAGE migration that is easily detected on western blot analysis . To determine whether expression of AND-34 might also regulate p130Cas PHOSphorylation in murine lens epithelium , we examined p130Cas in lens fiber and lens epithelial preparations from AND-34-/- and wild type mice . A significant portion of p130Cas in wild type lens epithelial cells ran as a slowly migrating species , consistent with a PHOSphorylated form of p130Cas (Figure 9B) . In contrast , this slowly migrating form of p130Cas was absent in the lens epithelial cells from AND-34-/- mice . As PI3K signaling have been implicated in both lens cell differentiation and AND-34 mediated Rac activation , we next sought to determine whether signaling by this pathway was altered in the lens epithelium from AND-34-/- mice [26] . PI3K activation results in PHOSphorylation of the serine/threonine kinase , Akt , at Thr308 by 3-phosphoinositide dependent protein kinase-1 ( PDK-1 ) and at Ser473 by the TORC2 ( target of rapamycin complex 2 ) complex [27,28] . Akt Ser473 PHOSphorylation was readily detectable in wild type lens epithelial cells but was markedly reduced in lens epithelial cell preparations from AND-34-/- mice ( Figure 9B ) . Total levels of AKT protein were comparable in wild type and knockout lens epithelial cells and AKT was detected at only low levels in lens fiber cells . These results demonstrate that loss of BCAR3 expression results in a reduction in both p130Cas and Akt Ser473 PHOSphorylation in murine lens epithelium .