SQSTM1 and chronic obstructive pulmonary disease: Although no differences were found in protein levels or gene-expression for the downstream autophagy-receptors sequestosome 1 (SQSTM1) and Calcium Binding And Coiled-Coil Domain 2 (CALCOCO2) (Fig. 1C,D), gene-expression of autophagy-receptor Optineurin (OPTN) was higher in COPD patients (Fig. 1D).