Once transcription has been activated, the extent of transcription of the late trypsin gene is proportional to the amount of protein present in the meal. In addition, the amount of late trypsin protein translation is controlled by the amount of amino acid released during digestion of the meal proteins. Regulation at both transcriptional and translational levels allows the midgut to adjust the amount of late trypsin with remarkable flexibility in response to a particular meal. Supported by NIH Grant A131951. Such surface structures are in the form of invadopodia or lamellipodia, which contact and remodel the extracellular matrix at the leading edge of the migratory cell.
Recent evidence suggests two distinct, proteolytic localization systems at invadopodia.
In human malignant melanoma cell line LOX, a specific integrin, alpha3 beta1, docks seprase and localizes its proteolytic activity at invadopodia that may allow the cell to break alpha5 betel integrin-matrix adhesion. We suggest that invadopodiumassociated proteases are ideal targets for the diagnosis and treatment of cancer as their presence in association with activated malignant and tissue cells may signal increased metastatic potential. SUNY at Stony Brook, Stony Brook, NY 117948691. Endogenous antiproteinases with specificities against individual proteinases may show impressive potency when studied in isolation, but the synergistic actions of multiple proteinases, along with other components of the inflammatory response or the invasive phenotype, may inactivate these endogenous defenses. Inhibitors of multiple proteinases should be especially effective under these circumstances, blocking pathologically excessive proteolysis and protecting endogenous antiproteinaes.