mRNA transcript levels of ABC1–4 genes in Y. lipolytica . Quantitative RT-PCR analyses of ABC1, ABC2, ABC3 and ABC4 in Y. lipolytica cells upon treatment with octane, nonane, decane, undecane and dodecane (C8-C12). Each value of qRT-PCR was normalized to β-actin expression levels and expressed as the fold change relative to the levels detected in control samples, which were cells without alkane treatment and set equal to 1. Error bars represent the standard deviation (SD) of three biological replicates. Primers for qRT-PCR are listed in Table S1.