Kerriann Badal, a first-year Integrative Biology (IB) Ph.D. student recently published in the top-tier, peer-reviewed scientific journal Cell Reports. Badal is being supervised by Dr. Sathya Puthanveettil of Scripps Florida and affiliate faculty member of the IB program. Kerriann, Sathya and colleagues published an exciting set of results in the January 2019 issue. Not only was the paper published in Cell Reports but also artwork related to their research report was chosen for the cover image! Badal et al. describe persistent changes in bidirectional mitochondrial transport and in the transcriptome of the presynaptic neuron following synapse formation. The abstract art cover represents changes induced in the presynaptic neuron by the postsynaptic cell. Cover art idea by Kerriann Badal, and illustration by Casey Bartlett.
The paper entitled "Synapse Formation Activates a Transcriptional Program for Persistent Enhancement in the Bi-directional Transport of Mitochondria" investigates mechanisms that regulate the bi-directional transport of mitochondria in neurons for maintaining functional synaptic connections are poorly understood. Here, we show that in the pre-synaptic sensory neurons of the Aplysia gill withdrawal reflex, the formation of functional synapses leads to persistent enhancement in the flux of bi-directional mitochondrial transport. In the absence of a functional synapse, activation of cAMP signaling is sufficient to enhance bi-directional transport in sensory neurons. Furthermore, persistent enhancement in transport does not depend on NMDA and AMPA receptor signaling nor signaling from the post-synaptic neuronal cell body, but it is dependent on transcription and protein synthesis in the pre-synaptic neuron. We identified ∼4,000 differentially enriched transcripts in pre-synaptic neurons, suggesting a long-term change in the transcriptional program produced by synapse formation. These results provide insights into the regulation of bi-directional mitochondrial transport for synapse maintenance.