Quantification of poly-ubiquitinated proteins in wild type Arabidopsis and amiNAA10 plants

Wild type Arabidopsis Col-0 plants and mutants depleted of the catalytic subunit of the ribosome-associated N-acetyltransferase A (NatA) complex (amiNAA10) were grown on soil for six weeks under short-day conditions (8h light, light intensity: 100 µE, 21 °C/18 °C temperature (day/night), 50 % humidity). Proteasome and deubiquitinase activity were inhibited at 10 am (2 h of light) by floating leaf discs on ½ Hoagland supplemented with 50 µM MG132 and 20 µM PR-619 for 5 h.