OBJECTIVETo investigate the mechanisms of DelCD11-279 of factor XIII subunit A mRNA in the pathogenesis of hereditary factor XIII deficiency.

METHODSThe recombinant plasmids containing pET-22b(+)/FXIIIA of normal subject and proband's mother and pET-22b(+)/FXIIIA-Del of the proband were constructed and transformed into E. coli BL21. Expressing protein was analyzed by the SDS-PAGE and purified by Ni-NTA resin. Purified proteins were detected by the Western-blot. The activity of purified protein was detected by the incorporation test with EZ-LinkTM5-(Biotinamido) Pentylamine.

RESULTSThe recombinant plasmids containing pET-22b(+)/FXIIIA and pET-22b(+)/FXIIIA-Del which constructed and identified successfully by enzyme digestion and PCR, were transformed into E. coli BL21 and efficiently expressed by IPTG induction. The molecular weights of expressing proteins are 83 200 and 51 900 by the SDS-PAGE. Expressing proteins were purified by Ni-NTA resin, and were proved to be human FXIIIA proteins by Western-blot. Purified protein activity of proband's mother and proband was 95.87% and 0 of the purified FXIIIA protein activity from the normal subject, respectively.

CONCLUSIONDelCD11-279 of FXIIIA mRNA which encoding a 464 amino acids of inactive FXIIIA protein is one of the molecular mechanisms resulting in FXIII deficiency in the patient.