Spatiotemporal expression patterns of histone acetyltransferase steroid receptor coactivator-1 in developing mouse heart

Abstract

Objective To study the spatiotemporal expression pattern of histone acetyltransferase steroid receptor coactivator-1(SRC1)in developing mouse heart,so as to explore the relationship of SRC1 with heart development.Methods The normal mouse hearts were collected at E7.5~E18 and 1 day and 3 months after birth;9 specimens were chosen for each time point to observe the spatial expression of SRC1 by immunohistochemistry technique,and 6 specimens of each time point were used to examine the temporal expression of SRC1 protein by Western blotting technique and to plot the time-dose curve.Results Immunohistochemistry showed no expression of SRC1 in the heart primordium at E7.5;only very weak SRC1 expression was found in the cardiac tube at E8.5~E9.5.Weak SRC1 expression was found in the trabeculae after E10.5 and relatively strong and widespread expression was found in other heart regions.Western blotting results demonstrated that SRC1 protein expression at E10.5 was significantly lower than those at E11.5 and E12.5(P0.05),and was not significantly different with those of other time points after E10.5(P0.05).SRC1 expression reached the peak at E11.5~E12.5,and there was no significant difference between the two time points(P0.05).SRC1 expression gradually decreased after E11.5~E12.5 till the adulthood,and there were no significant differences in the expression after E13.5(P0.05).Conclusion Widespread distribution of SRC1 is present in the developing mouse heart after E8.5,and the expression is in a dynamical spatiotemporal pattern,suggesting that SRC1 may take part in the overall regulation of the heart development,and it might has a closer relationship with the early induction of the heart septa.