Biochemical evidence for membrane-bound endoderm-specific alkaline phosphatase in larvae of the ascidian, Halocynthia roretzi.
An endoderm-specific alkaline phosphatase with a molecular mass of 86 kDa has been found in tadpole larvae of the ascidian, Halocynthia roretzi. The histochemical staining of sections of the larvae revealed that the enzyme is a membrane-associated protein. Two distinct bands were detected by zymographic technique on SDS/PAGE of the membrane preparation of the larvae. The two enzymes can be solubilized from the membrane preparation by sodium cholate and separated from each other by Cibacron blue-3GA affinity chromatography. The 86-kDa enzyme is likely to be the endoderm-specific one because the susceptibilities to alkaline phosphatase inhibitors coincide between the 86-kDa enzyme and that found in the endoderm of larvae by histochemical staining. The endoderm-specific alkaline phosphatase was purified and its N-terminal amino acid sequence was found to show little similarity to those of other proteins.
Kumano
G
G
Department of Life Science, Tokyo Institute of Technology, Japan.
Yokosawa
H
H
Nishida
H
H
D000469:Alkaline Phosphatase / Q000737:chemistry* / Q000302:isolation & purification; D000595:Amino Acid Sequence; D000818:Animals; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D004707:Endoderm / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006651:Histocytochemistry; D007202:Indicators and Reagents; D007814:Larva / Q000166:cytology / Q000201:enzymology; D008969:Molecular Sequence Data; D014561:Urochordata / Q000201:enzymology*
D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; D000469:Alkaline Phosphatase