an inositol-1-phosphoceramide + GDP-alpha-D-mannose <=> a mannosylinositol-1-phospho-N-acyl-sphingoid base + GDP + H(+)
an inositol-1-phosphoceramide + gdp-alpha-d-mannose <=> a mannosylinositol-1-phospho-n-acyl-sphingoid base + gdp + h(+)