Activating transcription factor 3 (ATF3) is a stress-responsive transcription factor and a well-established marker for nerve injury.3-5 ATF3 expression is induced in injured neurons and in pathological neurons damaged by disease or disease-associated gene mutants.6-9 ATF3 expression is also induced in motor neurons in presymptomatic stage ALS in response to pathological damage, and the number of ATF3+ motor neurons increases with disease progression.8 ATF3 initiates an injury-response transcriptional programme. The gene discussed is ATF3; the disease is amyotrophic lateral sclerosis.