Neurobiology fellows win competitive travel awards
By Eddy Ball
Travel awards are making it possible for two NIEHS Developmental Neurobiology Group trainees to attend a major international conference.
With their travel and living expenses covered, postdoctoral fellows Sabrina Robertson, Ph.D., and Jacqueline de Marchena, Ph.D., will spend Sept. 9-13 in Pacific Grove, Calif. at the Tenth International Catecholamine Symposium (XICS). The meeting will focus on leading-edge research on catecholamines, a class of neuromodulating chemicals in the central nervous system known as aromatic amines, including dopamine, norepinephrine, and epinephrine.
An opportunity to shine among the stars of catecholamine research
Judged on the basis of the quality of their abstracts, letters of interest and commitment to catecholamine research, and external recommendations, Irwin J. Kopin Travel Awardee Robertson and Catecholamine Society Travel Awardee de Marchena joined a select group of young researchers selected from applicants worldwide whose $650 registration fee is waived as part of the award.
During the symposium, Robertson and de Marchena will make poster presentations (see text box), as well as have an opportunity to network with some of the leading researchers in their field. The impressive lineup of plenary and session speakers includes National Institute on Drug Abuse Director Nora Volkow, M.D., several NIEHS Centers for Neurodegeneration Science grantees, and previous NIEHS Distinctive Lecture Series speakers Robert Lefkowitz, M.D., and Susan Amara, Ph.D.
“The list of speakers is really phenomenal,” Robertson said. “It’s a great opportunity for us to stand out.” De Marchena added, “We’re developing novel genetic tools in the lab, and we feel there’s a potential for collaborating with some of the prominent people in the field [of catecholamine research].”
Potentially groundbreaking findings about neuronal transmission
For their mentor, lead researcher Patricia Jensen, Ph.D., showing off her trainees’ work, using genetics to define different neuronal subtypes to better understand cellular diversity, could raise the group’s profile and lead to new productive collaborations. “The goal is to be invited as key speakers at the next international symposium,” said Jensen, who will also be attending the meeting in September.
“I’m just thrilled that their work is being recognized,” Jensen explained. “The neurons that synthesize norepinephrine play an important role in diverse functions such as attention, mood, appetite, memory, and stress. Select subsets of these neurons are differentially susceptible to disease and environmental insult. Our research presents a whole new way of studying subpopulations of noradrenergic neurons based on differential gene expression.”
The work coming out of Jensen’s group promises to overcome major obstacles to studying the mechanism of selective neuronal dysfunction and vulnerability to environmental factors.
Rounding out scientific training with career development
Along with their outstanding work at the bench during their two years with Jensen’s group, Robertson and de Marchena have also worked to hone career skills in such areas as lab management and grant writing. “We take advantage of as much as we can,” de Marchena said. “Tricia has been really supportive in letting us do anything we can to move our careers forward, and I think the Institute does a pretty good job of giving us access to all kinds of [career development] workshops and career advisors,” Robertson added.
With a sign on her office door proclaiming “I love my postdocs… They’re awesome,” Jensen underscores her appreciation for her trainees’ hard work. “They [de Marchena and Robertson] have a clear vision of their future,” she said, “[and] I’m doing everything I can to support them.”
New insights into neurotransmission
Jacqueline de Marchena — A novel approach to isolate the function of the galanergic subpopulation of the locus coeruleus (LC)
Using a dual recombinase-based genetic strategy to specifically label noradrenergic neurons that express the neuropeptide galanin (GAL) in a mouse model, de Marchana and her team determine where these neurons are located and to which brain areas they project. The team was the first to make a genetic model that takes advantage of a unique developmental pattern of gene expression, alongside a dual recombinase-based strategy, to knock out gene expression.
The researchers observed a developmental upregulation in the number of GAL-expressing LC neurons. Ultimately, they plan to use these tools to uncover how the specific loss of GAL in the LC affects neurodevelopment as well as learning and memory, with potential applications for treatment of neurological disorders, including depression, Alzheimer’s disease, and epilepsy.
Robertson SD, Plummer NW, de Marchena J, Goulding D, Harry J, Jensen P — Genetic Lineage Dictates Noradrenergic Fate and Function
Using a newly developed norepinephrine (NE) neuron-specific Flpo recombinase driver allele, Robertson’s team produced fate-mapping results that reveal a novel organization of the NE system based on genetic lineage. The researchers found that the projection patterns of these genetically defined NE subpopulations are unique.
The ability to assess the role of NE in prenatal brain development has long been hindered by the embryonic lethality associated with developmental disruption of peripheral NE. Thus, by capitalizing on these fate mapping results, the researchers have utilized a unique genetic solution to this long-held challenge in the monoamine field. Indeed, mice expressing TeTxLC within the NE R1 lineage survive to adulthood and, for the first time, are investigated here for the behavioral consequences associated with silencing the LC throughout development.