The rupee gained 15 paise to 55 rupees 43 paise against the US dollar in early trade today as the American currency weakened against euro overseas.Dollar selling by exporters and banks amid a higher opening in the domestic equity market also supported therupee.Euro rose against the American currency overseas ahead of the European Central Bank meets on Thursday.The rupee had lost 24 paise to close at 55.58 against the dollar yesterday on heavy month-end dollar demand form oilimporters even as stock markets had gained 300 points