title: Sequences and expression patterns of alkaline phosphatase isozymes in preattachment bovine embryos and the adult bovine.
abstract: We report the cloning and partial sequences of two novel bovine tissue-specific alkaline phosphatase (AP) isozymes (TSAP2 and TSAP3) from in vitro-produced bovine blastocysts. Using a reverse-transcribed polymerase chain reaction (RT-PCR)-based assay for mRNA expression and in vitro-produced preattachment bovine embryos, TSAP2 mRNA was detected first at the four-cell stage prior to the major burst of embryonic transcription in cattle and TSAP3 at the eight-cell stage with the major burst in transcription. Furthermore, the transcription of TSAP2 and TSAP3 displays a curious "on-off" pattern during early cleavages between 40 and 120 hr after insemination. Activity of bovine AP, measured by an azo-dye coupling technique, indicates that at least one AP isozyme is functional in oocytes and embryos throughout bovine preattachment development. However, maternal and embryonic-derived AP activity may have different cell-surface distributions. This novel expression pattern of the bovine AP isozymes could provide a useful tool for identifying and clarifying the events controlling transcription and gene expression during early embryo development.
authors.affiliation: Department of Biomedical Sciences, University of Guelph, Ontario, Canada.
authors.forename: K
authors.initials: K
authors.lastname: McDougall
authors.forename: J
authors.initials: J
authors.lastname: Beecroft
authors.forename: C
authors.initials: C
authors.lastname: Wasnidge
authors.forename: W A
authors.initials: WA
authors.lastname: King
authors.forename: A
authors.initials: A
authors.lastname: Hahnel
mesh_terms: D000469:Alkaline Phosphatase / Q000096:biosynthesis / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D001755:Blastocyst / Q000201:enzymology*; D002417:Cattle; D018076:DNA, Complementary; D015870:Gene Expression; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D007527:Isoenzymes; D000469:Alkaline Phosphatase