A Guide for Graduate Students Interested in Postdoctoral Positions in Biology Education Research

Intended as a resource for life sciences graduate students, this essay discusses the diversity of postdoctoral positions in biology education and the careers to which they lead. The authors also provide advice to help graduate students develop the skills necessary to obtain a biology education research postdoctoral position

RPM-1 suppressors Act in synapse formation and axon termination in Caenorhabditis elegans

One prevailing question in developmental neurobiology is how neurons form precise connections with their targets. The PHR (Pam/Highwire/RPM-1) protein family is highly conserved from mammals to zebrafish and is important for both axon termination and synapse formation. Caenorhabditis elegans RPM-1 (Regulator of Presynaptic Morphology) is a large protein with multiple domains. One role of RPM-1 is to negatively regulate a mitogen- activated protein kinase (MAPK) cascade via proteasomal degradation. To learn more about the RPM-1 signaling pathway, a genetic suppressor screen was utilized to identify additional molecules downstream of RPM-1. Suppressors were initially tested by non-complementation against known rpm-1 suppressors to identify novel suppressors. One prevailing question in developmental neurobiology is how neurons form precise connections with their targets. The PHR (Pam/Highwire/RPM-1) protein family is highly conserved from mammals to zebrafish and is important for both axon termination and synapse formation. Caenorhabditis elegans RPM-1 (Regulator of Presynaptic Morphology) is a large protein with multiple domains. One role of RPM-1 is to negatively regulate a mitogen- activated protein kinase (MAPK) cascade via proteasomal degradation. To learn more about the RPM-1 signaling pathway, a genetic suppressor screen was utilized to identify additional molecules downstream of RPM-1. Suppressors were initially tested by non-complementation against known rpm-1 suppressors to identify novel suppressors. One prevailing question in developmental neurobiology is how neurons form precise connections with their targets. The PHR (Pam/Highwire/RPM-1) protein family is highly conserved from mammals to zebrafish and is important for both axon termination and synapse formation. Caenorhabditis elegans RPM-1 (Regulator of Presynaptic Morphology) is a large protein with multiple domains. One role of RPM-1 is to negatively regulate a mitogen- activated protein kinase (MAPK) cascade via proteasomal degradation. To learn more about the RPM-1 signaling pathway, a genetic suppressor screen was utilized to identify additional molecules downstream of RPM-1. Suppressors were initially tested by non-complementation against known rpm-1 suppressors to identify novel suppressors. My dissertation provides characterization of a novel protein involved in synaptogenesis and the addition of mapping information for additional proteins important in synapse formation downstream of RPM-

A Ubiquitin E2 Variant Protein Acts in Axon Termination and Synaptogenesis in Caenorhabditis elegans

In the developing nervous system, cohorts of events regulate the precise patterning of axons and formation of synapses between presynaptic neurons and their targets. The conserved PHR proteins play important roles in many aspects of axon and synapse development from C. elegans to mammals. The PHR proteins act as E3 ubiquitin ligases for the dual-leucine-zipper-bearing MAP kinase kinase kinase (DLK MAPKKK) to regulate the signal transduction cascade. In C. elegans, loss-of-function of the PHR protein RPM-1 (Regulator of Presynaptic Morphology-1) results in fewer synapses, disorganized presynaptic architecture, and axon overextension. Inactivation of the DLK-1 pathway suppresses these defects. By characterizing additional genetic suppressors of rpm-1, we present here a new member of the DLK-1 pathway, UEV-3, an E2 ubiquitin-conjugating enzyme variant. We show that uev-3 acts cell autonomously in neurons, despite its ubiquitous expression. Our genetic epistasis analysis supports a conclusion that uev-3 acts downstream of the MAPKK mkk-4 and upstream of the MAPKAPK mak-2. UEV-3 can interact with the p38 MAPK PMK-3. We postulate that UEV-3 may provide additional specificity in the DLK-1 pathway by contributing to activation of PMK-3 or limiting the substrates accessible to PMK-3