Differential expression of embryonic and maternal activity-dependent neuroprotective protein during mouse development

OBJECTIVE: Activity-dependent neuroprotective protein (ADNP) potently enhances the survival of neurons and is regulated by vasoactive intestinal peptide, which also mediates postimplantation mouse embryonic growth. The objective of this study was to characterize ADNP in mouse embryonic tissues throughout development. STUDY DESIGN: Developmental tissues (embryo, decidua, placenta) from timed pregnant C57B16/J mice were harvested on days 6 though 18. To evaluate ADNP expression, RNA was extracted from at least three samples from three different mice per day. Five micrograms of total RNA from each sample was used per reverse transcriptase-polymerase chain reaction. Immunocytochemistry with anti-ADNP-derived peptide immunoglobulin and anti-gammadelta T-cell receptor was performed on 20 mum thick fixed sections of day 9.5 uteri. RESULTS: Embryonic ADNP messenger RNA (mRNA) has a temporal pattern with greater amounts present from gestational days 9 to 16. Placental ADNP mRNA was uniformly expressed on gestational days 11 to 18. Levels of decidual ADNP mRNA were greatest early in gestation and declined until delivery. Within the decidua, ADNP and gammadelta T-cell receptor immunoreactivity was present in the same cells. CONCLUSION: The expression of ADNP during pregnancy supports a developmental role for this protein. These data indicate both embryonic and maternal sources of ADNP during the critical period of organogenesis.