Ps. Glas et al., OXIDASE ACTIVITY ASSOCIATED WITH THE ELEVATION OF THE PENAEOID SHRIMPHATCHING ENVELOPE, The Biological bulletin, 189(1), 1995, pp. 13-21
When penaeoid shrimp spawn into seawater, the ova elevate a hatching e
nvelope (HE) within 30-50 min. By 60 min after spawning, the bilayered
HE is completely formed. In other animal systems, peroxidatic enzymes
are responsible for the hardening of the extraembryonic coat. In this
study, observations are made consistent with the involvement of an ox
idase in the assembly of the shrimp HE. As observed by electron micros
copy, eggs of Sicyonia ingentis and Trachypenaeus similis spawned in s
eawaters containing peroxidase inhibitors had abnormally assembled HEs
compared to control eggs in seawater. Dihydrotetramethylrosamine, an
oxidase-sensitive fluorescent dye, supravitally stained the cortex of
S. ingentis eggs at the time of initial HE formation. The HE fluoresce
d from elevation (40-50 min postspawn in S. ingentis) until 60-70 min
postspawn. By first cleavage (90-120 min postspawn), HE staining was n
o longer visible, although staining persisted in the egg cortex. In eg
gs treated with the peroxidase inhibitors 3-amino-1,2,4-triazole or so
dium sulfite, the egg cortex fluoresced, but no fluorescence appeared
in the HE before, during, or after its elevation.