Fig. 2.

Downregulated Pax3 probably resulted in reduced expression of FPN1 in PE placental tissues.

Both GSE50783 and GSE44667 data sets provided the data of genes that were aberrantly expressed in placental tissues from PE patients and physiologically normal pregnancies. Transcript factors that were implicated in the transcription of FPN1 were predicted using a Bioinformatics analysis website (http://bioinfo.life.hust.edu.cn/hTFtarget#!/). We analyzed the intersection between the aberrantly expressed genes and transcript factors targeting FPN1. As indicated by the Venn diagram, three of the transcript factors (Pax3, POU3F2 and BHLHE40) were found to be aberrantly expressed in placental tissues from PE patients (A). Bioinformatics analysis website Jasper (http://jaspar2016.genereg.net/) gave the highest score on POU3F2 followed by Pax3 (B). We performed western blot to test the protein levels of these three transcript factors in placental tissues from PE patients and physiologically normal pregnancies (C). Pax3 protein level was down-regulated in PE placental tissues, while BHLHE40 protein level was significantly up-regulated. Results from immunohistochemistry assay (D) and GSE10588 data set (E) also confirmed the down-regulation of PAX3 in PE placental tissues. Another transcript factor-predicting websit, Jasper (http://jaspar2016.genereg.net/), showed the motif, a sequence in gene promoter that is recognized by Pax3 (F). Moreover, Jasper revealed two potential binding sites of transcription factor Pax3 at the promoter of FPN1 and SLC7A11 genes. Our following study was performed to identify the regulatory effect of Pax3 on FPN1 and SLC7A11 expression. *p < 0.05, **p < 0.01, compared with the normal group.