Fig. 2. p24 protein expression in Xenopus pituitary. The neurointermediate lobe (NIL) was manually dissected from the anterior lobe (AL) of the pituitary of black- or white-adapted Xenopus. 20 µg of NIL and AL extracts were resolved together with tissue extracts from brain and hypothalamus (60 µg each) by SDS-PAGE. For immunoblotting, antisera directed against sequences in the lumenal domains of the respective p24 proteins or the anti-C antiserum recognizing Xp24₁ and -₂ were used. The asterisk indicates an AL protein band presumably resulting from crossreactivity of the anti-Xp24₁ antiserum with an abundant 23 kDa protein (likely growth hormone/prolactin).