ThewstGene Regulates Multiple Forms of Thymocyte Apoptosis

Mice homozygous for the autosomal recessive mutation Wasted (wst/wst) display a disease characterized by immunodeficiency, cerebellar dysfunction, and sensitivity of their hematopoeitic cells to gamma radiation. Wasted mice die by 30 days of age. In this report, we show that the Wasted thymus shows evidence of dramatically increased apoptosisin situ.Moreover,wst/wstthymocytes are more sensitive to apoptosis induced by gamma radiation, heat shock, α-CD3 stimulation, and dexamethasone treatmentin vitro.Thus,wstgene is a regulator of thymocyte apoptosis bothin vitroandin vivo.The elevated levels of thymocyte apoptosis may be a major contributor to the lymphoid dysfunction and ultimate death inwst/wstmice.