Plays a role in the cleavage of a residual cap structure following the degradation of mRNAs by the 3'->5' exosome-mediated mRNA decay pathway. Stress-induced regulatory protein that modulates the m7GpppX diphosphatase activity of DCS1. Homodimer. Forms heterodimer with DCS2; the interaction inhibits the DCS1 scavenger decapping activity during post-diauxic growth. Predominantly cytoplasmic. Localizes close to the perinuclear space before the diauxic growth shift. Recruited to the P-body after the post-diauxic growth shift. Colocalizes with the decapping activator protein LSM1 at P-body. By nutrient, osmotic, oxidative and heat stress. Up-regulated during the diauxic shift. Present with 1870 molecules/cell in log phase SD medium. Belongs to the HIT family. Although strongly related to the DcpS enzyme, it has apparently no scavenger mRNA-decapping activity. Extended N-terminus. Extended N-terminus.