Biomarkers.

Background: Alzheimer's disease (AD), the most common type of dementia, affects at least twenty-four million people globally, yet, the causation, mechanisms of progression, and therapeutic strategies remain elusive. Currently, tRNA-derived RNA fragments (tRFs), a family of recently discovered small non-coding RNAs (sncRNAs), have surfaced as promising biomarkers for many diseases, including AD. Our work revealed that several AD-impacted tRFs in human hippocampus, CSF, and serum.

represses short-wavelength cone genes to preserve long-wavelength cone and rod photoreceptor identity.

The role of transcription factors in photoreceptor gene regulation is fairly well understood, but knowledge of the cell-type-specific function of transcriptional cofactors remains incomplete. Here, we show that the transcriptional corepressor promotes rod differentiation and represses short-wavelength cone genes in long-wavelength cones in zebrafish. In retinas, red cones are transformed into hybrid red/ultraviolet (UV) cones, green cones are absent, the number of blue cones is approximately doubled, and the number of rods is greatly reduced.