Meeting Abstract
Aplysia californica is a valuable model organism for the cellular analysis of behavior, including learning and memory. The neural circuits controlling the defensive withdrawal reflexes of this organism have been analyzed extensively, to the level of individual, functionally identified neurons. These circuits are capable of several forms of learning, including sensitization, habituation, and classical conditioning. We utilized single-cell RNA-seq to profile individual sensory and motor neurons known to control both the tail-withdrawal reflex (TWR) and siphon/gill-withdrawal reflex (S/GWR). We discovered a multitude of transcripts to be differentially expressed between the pleural ventrocaudal (VC) sensory neurons of the TWR and the abdominal LE sensory neurons of the S/GWR. These included transcripts encoding glutathione S-transferase, zinc-finger containing proteins, RNA-binding and processing proteins, a ribonucleoprotein, a 5-hydroxymethylcytosine-binding protein, and multiple uncharacterized transcripts (among others). We also analyzed differential expression between the LFs motor neurons contributing to siphon withdrawal of the S/GWR and the L7 motor neurons contributing to the gill withdrawal component of the S/GWR. Several transcripts were found to be differentially expressed including those encoding kinesin heavy chain, a G protein coupled receptor kinase, an NFX1-type zinc finger protein, a polyadenylate-binding protein, and uncharacterized transcripts. These differentially expressed transcripts may help us to distinguish between functionally similar neurons involved in defensive withdrawal reflexes and highlight the unique repertoire of molecules utilized by each circuit. Supported by NSF and NIH.
