Expressions of bone development related protein BMP5, HMGA1 and PLAG1 varied with the expression of HOXA1 in mouse osteoblasts

Abstract

Background: To investigate if the expression of bone development causal genes BMP5, HMGA1 and PLAG1 in animals could be affected by HOXA1 with small molecule interfering RNA (siRNA) experiment in mouse embryonic osteoblast precursor cells.Methods: Four HOXA1 target siRNA sequences (siRNA1-4) were designed to transfect Mc3t3-e1-24 cells with LipofectamineTM2000 liposomes. The transcription and protein expression levels of HOXA1 were compared between siRNA groups. The mRNA and protein expressions of BMP5, HMGA1 and PLAG1 were compared before and after HOXA1 transfection. The mRNA expressions of bone cell proliferation marker genes Runx2, ALP, OCN, FGF3 and IGF2 were measured.Results: SiRNA1 has the strongest interference efficiency. The expressions of HOXA1 transfected with siRNA1 in Mc3t3-e1-24 cells were significantly down-regulated (P < 0.05). After the expression of HOXA1 was suppressed, the mRNA and protein expressions of BMP5 (P < 0.01), HMGA1 (P < 0.05) and PLAG1 (P < 0.05) were significantly increased. And, the transcription levels of Runx2, ALP, OCN, FGF3 and IGF2 genes were significantly increased (P < 0.05, P < 0.01), which indicated the increasing of osteoblast proliferation.Conclusions: In mouse embryonic osteoblast precursor cells, the expression levels of BMP5, HMGA1 and PLAG1 could be affected by the inhibition of HOXA1, and the changes of their expression levels were consistent that they all increased with the decreased HOXA1 and the increased cell proliferation. The molecular mechanisms under the interaction among these genes needs to be further studied.