The cutin-deficient mutant cud1 is not affected in the polymerization of 9(10),16-dihydroxyhexadecanoic acid. A, Quantification of major cutin monomers. 16-OHC16 acid, 16-Hydroxyhexadecanoic acid; 9(10),16-diOHC16 acid, 9(10),16-dihydroxyhexadecanoic acid; 9-OH-1,16-C16 diacid, 9-hydroxy-1,16-hexadecanedioic acid. B, Esterification level of 9(10),16-dihydroxyhexadecanoic acid OH groups from cud1 cutin compared with wild-type (WT) and cus1-a cutins. Data are expressed as mean values, and error bars represent sd (n = 3). Significant differences from the wild type are indicated by asterisks (Student’s t test; *, P < 0.05 and **, P < 0.01).