© 2016 The Authors. There is a considerable interest in understanding the dependence of one-nucleon removal cross sections on the asymmetry of the neutron Sn and proton Sp separation energies, following a large amount of experimental data and theoretical analyses in a framework of sudden and eikonal approximations of the reaction dynamics. These theoretical calculations involve both the single-particle cross section and the shell-model description of the projectile initial state and final states of the reaction residues. The configuration mixing in shell-model description of nuclear states depends on the proximity of one-nucleon decay threshold but does it depend sensitively on Sn-Sp? To answer this question, we use the shell model embedded in the continuum to investigate the dependence of one-nucleon spectroscopic factors on the asymmetry of Sn and Sp for mirror nuclei 24Si, 24Ne and 28S, 28Mg and for a series of neon isotopes (20≤A≤28).