2.2. Preparation of hemolymph samples and tissue extracts
Hemolymph was bled from the pericardial sinus with a
hypodermic syringe provided with an 18 gauge needle and
containing 1 mM PMSF. The hemolymph was allowed to clot
overnight at 4 -C. The serum collected by centrifugation at
2500g for 20 min at 4 -C to remove residues and cells was
then stored at 20 -C.
Ovaries and the hepatopancreas from vitellogenic females or
testis from mature shrimps were freshly dissected out and
washed three times with 50 mM Tris–HCl, pH 7.5 containing
0.15 M NaCl and 1 mM PMSF (TBSP). The tissues were then
homogenized using a hand held homogenizer in the same
buffer. The homogenate was centrifuged at 2500 g for 30 min
at 4 -C and the supernatant was collected and subjected to
electrophoresis, double immunodiffusion, ELISA and Western
blotting. Protein was determined by the method of Markwell et
al. (1978) using BSA as the standard.