Table 4. H3K27me3 ChIP-seq read mapping and purity information.

Sample	No. trimmed reads	% of mapped reads	No. of Ler reads	No. of Col reads	Purity (%)
Ler x Col 4x	30,337,933	68.3	1,844,412	1,563,394	95.7
Replicate 1 Input
Ler x Col 4x	22,644,505	73.3	1,439,255	1,211,446
Replicate 1 H3 ChIP
Ler x Col 4x	27,448,642	61.5	1,214,486	681,823
Replicate 1 H3K27me3 ChIP
Ler x Col 4x	40,500,367	66.4	2,720,117	2,483,912	97.7
Replicate 2 Input
Ler x Col 4x	32,322,049	71.9	2,304,635	2,068,612
Replicate 2 H3 ChIP
Ler x Col 4x	34,978,215	63	2,681,981	1,636,717
Replicate 2 H3K27me3 ChIP

The purity of INTACT-extracted endosperm nuclei is indicated in the last column and was calculated as described in Moreno-Romero et al. (2017).