Premium
A novel antigen Apsi is expressed in a half population of endoderm cells in normal and LiCI‐treated starfish embryos
Author(s) -
Yoshikawa ShunIchi
Publication year - 1996
Publication title -
development, growth and differentiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.864
H-Index - 66
eISSN - 1440-169X
pISSN - 0012-1592
DOI - 10.1046/j.1440-169x.1996.t01-3-00007.x
Subject(s) - endoderm , ectoderm , biology , mesoderm , medicine , embryo , endocrinology , embryogenesis , microbiology and biotechnology , cellular differentiation , embryonic stem cell , genetics , gene
A novel antigen, Apsi, revealed a tissue specific expression in the starfish embryo. Apsi was detected in the stomach and intestine of the bipinnaria larva by immunofluorescence microscopy, but was not detected in the esophagus or ectoderm. The expression of Apsi was zygotic and first detected at day 3 after fertilization. Using this antigen as a molecular marker, the effect of LiCI treatment on development was examined by counting the cell number of each germ layer and endoderm tissues on serial paraffin sections. At day 5 larva stage, the ratio of the cell number of ectoderm, esophagus, Apsi‐expressing tissue (stomach and intestine) and mesoderm was 75:10:10:5. The corresponding ratio in LiCI‐treated embryo was 68:14:14:4. LiCI treatment increased the cell number of endoderm by 40%, at the expense of a 10% decrease in the cell number of ectoderm. In intact embryos, approximately half the endoderm cells expressed Apsi antigen, while the other half did not. LiCI treatment did not change this ratio of Apsi expression in endoderm tissues. These observations indicate that LiCI treatment of early blastulae affects the commitment of ectoderm/endoderm but does not affect the differentiation of the esophagus/stomach and intestine.