Isoform 2 of Endophilin-B2

Endophilin-B2 (SH3GLB2) is a membrane-associated protein implicated in vesicular trafficking and endocytic processes (UniProt: Q9NR46-2). The protein contains SH3 domains characteristic of endocytic regulatory proteins and participates in membrane remodeling pathways essential for neuronal function. Isoform 2 is a 44.8 kDa variant encoded by the SH3GLB2 gene in humans.

Endophilin-B2 localizes to intracellular membrane compartments and is involved in synaptic vesicle dynamics and clathrin-mediated endocytosis. While not flagged for specific tissue pathology in the UniProt record, the protein's role in membrane trafficking connects it to neuronal homeostasis and synaptic plasticity relevant to neurodegeneration.

In Alzheimer's disease, this isoform shows elevated protein abundance in post-mortem AD brain tissue compared to age-matched controls (Chaparral AD proteomics). Specifically, Endophilin-B2 isoform 2 is upregulated with a mean log2 fold-change of +0.29 in human post-mortem AD brain across subcellular fractions (TMT-labeled quantitative proteomics). This upregulation may reflect compensatory responses or pathological alterations in vesicular trafficking during AD neurodegeneration.