Analysis of xylan structure and quantity by DASH. Stem cell wall xylan of Wild type (WT) and mutant Arabidopsis irx7, irx8, irx9, irx14 and parvus was hydrolysed with xylanase Cj Xyn10A, and the resulting oligosaccharides mixed with quantitation standards QS1-QS4. (A) Aligned electropherograms showing Cj Xyn10A digests. † denotes background peaks. (B) Identification of xylan reducing end oligosaccharide (REO) in WT is confirmed by co-migration with a standard, and absence in irx7. (C) Amount of xylan and (D) Percentage of [Me]GlcA branching of xylan in WT and irx mutants, quantified from Cj Xyn10A digests, and analysed using DASHboard. Data are the average of three technical replicates, and are shown +/- s.d. Values significantly different from WT are marked with a * (Student’s t-test, p < 0.05).