Two distinct proteolytic activities were demonstrated in developing ovarian follicles of the stick insect Carausius morosus using aldolase as a substrate. One has an optimum activity around pH 5 and it is strongly inhibited by pepstatin A. Because of these properties, it is classifiable as an aspartic proteinase. The second one has an alkaline pH optimum and it is inhibited by aprotinin. Based on these properties it is classifiable as a serine, trypsin‐like, proteinase. This latter activity has also been visualized as a negatively stained protein fraction of about 26 kD on polyacrylamide gels containing casein as substrate. While the aspartic proteinase is predominantly associated with follicles approaching chorionogenesis, the serine proteinase is restricted to immature follicles and disappears prior to completion of ovarian development.
On the occurrence of proteolytic activities in ovarian follicles of the stick insect Carausius morosus (Br.)
CECCHETTINI, ANTONELLA
1994-01-01
Abstract
Two distinct proteolytic activities were demonstrated in developing ovarian follicles of the stick insect Carausius morosus using aldolase as a substrate. One has an optimum activity around pH 5 and it is strongly inhibited by pepstatin A. Because of these properties, it is classifiable as an aspartic proteinase. The second one has an alkaline pH optimum and it is inhibited by aprotinin. Based on these properties it is classifiable as a serine, trypsin‐like, proteinase. This latter activity has also been visualized as a negatively stained protein fraction of about 26 kD on polyacrylamide gels containing casein as substrate. While the aspartic proteinase is predominantly associated with follicles approaching chorionogenesis, the serine proteinase is restricted to immature follicles and disappears prior to completion of ovarian development.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
