Topic: ectopic synapses

The large, homologous proteins Bassoon (Bsn) and Piccolo are part of the cytomatrix at the active zone (AZ) of conventional chemical synapses, where they can partially compensate for each other’s function. At the highly specialized photoreceptor ribbon synapses, Piccolino (Pclo), a C-terminally truncated splice variant of Piccolo, is the functional partner of Bsn. In earlier studies, we detected free-floating photoreceptor synaptic ribbons and disrupted AZs in Bsn single knockout (sKO) mice1 and a loss of the plate‑like ribbon structure, but attached photoreceptor synaptic ribbons, in Pclo sKO