Hist2h2be (histone cluster 2, H2be) is expressed exclusively in olfactory chemosensory neurons. Expression is reduced by sensory activity, and it alters gene expression and promotes neuronal cell death in mature olfactory sensory neurons, potentially modulating olfactory neuronal population dynamics to adapt the olfactory repertoire to the environment. These transgenic mice carry flag-tagged mouse Hist2h2be (histone cluster 2, H2be) downstream of the rat Omp (olfactory marker protein) promoter. The flag reporter facilitates and characterization and unambiguous identification of Hist2h2be and distinguishes it from canonical H2B. Immunofluorescent examination in the main olfactory epithelium (MOE), reveals a 10 fold increase in nuclear expression in a pattern similar to that of endogenous OMP, with the exception of a small patch of neurons in the medial part of the MOE that lack expression. High levels of FLAG-H2BE are seen in all mature olfactory neurons except for a subset in zone 2. Transgenic mice display higher levels of apoptosis among olfactory sensory neurons in the MOE.