Document Type



Alkaline phosphatase (AP) activity is stage specific in mouse embryos and may be associated with compaction and separation of trophectoderm from inner cell mass in preimplantation development. We previously sequenced a cDNA and two mouse AP genes that could contribute to the AP activity in embryos. Oligonucleotide primers were constructed from the three sequences and used in the reverse transcription-polymerase chain reaction technique to establish that two of the three AP isozymes are transcribed during preimplantation development. The predominant transcript (E-AP) is from a gene highly homologous to the human tissue-specific APs, but different from the mouse intestinal AP. Tissue non- specific (TN) AP also is transcribed, but there is approximately 10 times less TN-AP than E-AP tran- script. The TN-AP isozyme is the predominant tran- script of 7 to 14 day embryos and primordial germ cells. A switch in predominance from E-AP to TN-AP must occur during early postimplantation development. This study establishes a framework for experiments to determine the functions of the two isozymes during preimplantation development.


Obstetrics and Gynecology


Copyright (1990) The Company of Biologist Limited. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Company of Biologist Limited. This article is the publisher’s version (Company of Biologist Limited), previously appearing in DEVELOPMENT (110, 1990, pp. 555-564). Also available online at