[Screening of differentially expressed genes in placentas with hepatitis B virus infection by suppression subtractive hybridization technique].

OBJECTIVE

To screen differentially expressed genes in placentas with hepatitis B virus (HBV) infection and to discuss the molecular mechanism of HBV intrauterine infection.

METHODS

Thirty placenta tissue specimens from HBsAg and HBV DNA positive pregnant women were used as the study group and 30 placenta tissue specimens from normal pregnant women with HBsAg and HBV DNA negativity were served as the control group. The suppression subtractive hybridization (SSH) technique was used. Total RNAs of placenta tissue of the study group were mixed as the tester, and total RNAs of placenta tissue of the control group were mixed as the driver. A subtractive cDNA library was constructed by PCR-selective cDNA subtraction systems. Amplifications of the library were carried out with E. coli strain DH5alpha by reverse spot hybridization. RT-PCR confirmed that phosphatidylinositol 3-kinase (PI3K) was up-regulated in placenta tissue with HBV infection.

RESULTS

Colony PCR showed that the clones contained 200 - 1000 bp inserts. Thirty five clones were confirmed by reverse spot hybridization and analyzed by sequencing and bioinformatics. Thirty three known genes and 2 genes with unknown function were obtained. RT-PCR preliminarily confirmed that PI3K gene was up-regulated in HBV infected placenta.

CONCLUSIONS

The differentially expressed genes in placentas with hepatitis B virus (HBV) infection using SSH technique has been screened out successfully. These differentially expressed genes encoding proteins participating in cell vital metabolism and malformation, and signal conduction-antiapoptosis pathway. This finding brings some new clues for studying the mechanisms of HBV intrauterine infection.