Regional Differences in Catheptic Activity inXenopus laevisembryos

Open Access
Publisher Website
Google Scholar
Abstract
That the intracellular proteolytic enzymes known collectively as ‘cathepsins’ may have a special function in newly forming tissues was first suggested by the findings of Orechowitsch, Bromley, & Kusmina (1935). These authors observed that in certain amphibians regenerating tail-tissue had a much higher catheptic activity than the normal, non-regenerating tail. Their findings have been confirmed and extended recently in work on Xenopus laevis larvae, where it has been shown (Jensen, Lehmann, & Weber, 1956) that a peak in catheptic activity is reached in the regenerating tail-tip on about the 7th day after amputation. A further finding (Deuchar, Weber, & Lehmann, 1957) was that the early regenerate had a much higher catheptic activity relative to total nitrogen than had the stump-tissue immediately adjacent to it. The cathepsins seemed, therefore, to have the highest activity in the region of most active protein synthesis.