A long noncoding eRNA forms R-loops to shape emotional experience-induced behavioral adaptation.

Emotional experiences often evoke neural plasticity that supports adaptive changes in behavior, including maladaptive plasticity associated with mood and substance use disorders. These adaptations are supported in part by experience-dependent activation of immediate-early response genes, such as (neuronal PAS domain protein 4). Here we show that a conserved long noncoding enhancer RNA (lnc-eRNA), transcribed from an activity-sensitive enhancer, produces DNA:RNA hybrid R-loop structures that support three-dimensional chromatin looping between enhancer and proximal promoter and rapid gene induction.

Isomerization of Asp is essential for assembly of amyloid-like fibrils of αA-crystallin-derived peptide.

Post-translational modifications are often detected in age-related diseases associated with protein misfolding such as cataracts from aged lenses. One of the major post-translational modifications is the isomerization of aspartate residues (L-isoAsp), which could be non-enzymatically and spontaneously occurring in proteins, resulting in various effects on the structure and function of proteins including short peptides. We have reported that the structure and function of an αA66-80 peptide, corresponding to the 66-80 (66SDRDKFVIFLDVKHF80) fragment of human lens αA-crystallin, was dramatically altered by the isomerization of aspartate residue (Asp) at position 76.

A single Asp isomer substitution in an αA-crystallin-derived peptide induces a large change in peptide properties.

The eye lens is mainly composed of crystallins, which undergo modifications such as oxidation, deamidation and isomerization with aging. Asp58, Asp76, Asp84, and Asp151 residues of αA-crystallin are site-specifically isomerized to L-iso, D-, and D-iso isomers in aged-related cataract lenses. In addition, an αA66-80 peptide, corresponding to the 66-80 (SDRDKFVIFLDVKHF) fragment of human αA-crystallin, is detected in aged lens.