Role of enzymes in the mechanism of shell penetration by the muricid gastropod, Thais lapillus (L.)
The role of the boring organ in the mechanism of shell penetration by Thais lapillus (L.), a muricid gastropod, has been investigated by cytochemistry and biochemistry. Sites of acid phosphatase and carbonic anhydrase activity were localized and the biochemical activities of these enzymes were measured in the boring organ of both nonboring and actively boring animals. The lysosomal marker enzyme, acid phosphatase, was investigated to assess the role of lysosomes in the boring mechanism. Acid phosphatase activity was localized on the microvillar membranes of the epithelial cells of the boring organ. There was no significant difference in the biochemical activity of acid phosphatase between actively boring and nonboring specimens. Carbonic anhydrase was localized prominently in the epithelium of the boring organ. The microvilli showed no localization but all other regions of the epithelium were dominated by reaction product. The boring organ demonstrated high levels of carbonic anhydrase activity but no significant difference could be detected between actively boring and nonboring specimens. The possible involvement of these enzymes and their role in the mechanism of shell penetration by muricid gastropods has been discussed.