Additionally, similar directional changes in transcript levels for Atf5, Hsp10 and mtHsp70 and protein levels for LONP1, CLPP and SIRT3 (Fig. 5) were observed in the lungs of HPS-2 mice, illustrating the reproducibility of our findings across in vivo and in vitro model systems. Here, ATF5 is linked to Hermansky-Pudlak syndrome.