John D. Boughter, Jr., PhD

John D. Boughter, Jr., Ph.D.

Associate Professor
Department of Anatomy and Neurobiology
The University of Tennessee
Health Science Center


The University of Tennessee Health Science Center
855 Monroe Avenue, Suite 515
Memphis, TN 38163
Phone: (901) 448-1633
Fax: (901) 448-7193
Email: John D. Boughter, Jr.

 

Education

  • Undergraduate Institution: Binghamton University
  • PhD Institution: Florida State University, Psychology Department, Neuroscience Program
  • Postdoctoral: University of Maryland School of Medicine, Department of Anatomy & Neurobiology

Research Interests

Ingestive decisions play a key role in a number of human conditions including obesity, diabetes, anorexia, hypertension, and coronary artery disease. My lab uses neuroanatomical, neurophysiological, imaging and behavioral approaches towards the study of ingestive behaviors in laboratory mice.

Central pathways for taste and reward

The sense of taste is the most important factor in regulating ingestive decisions. This is not merely due to the location of taste buds and receptors at the beginning of the alimentary canal; it has long been appreciated that palatable tastes are inherently rewarding, and taste stimuli such as sucrose activate pathways in the CNS involved in homeostasis, ingestion and reward. We are studying these pathways in the mouse brain using functional neuroanatomical approaches including tract tracing and behavior-elicited immediate early gene (cFos) expression. In recent research, we have shown the taste-responsive neurons in a taste “center” of the brainstem (the parabrachial nucleus; PBN) project directly to a key midbrain substrate of reward processing, the ventral tegmental area (VTA). We have also demonstrated using both cFos expression and awake physiological recording that neurons in the VTA respond to tastes.

illustration
A: Schematic of ascending and descending gustatory pathways in the mouse (from Smith and Boughter, 2009). B. Sucrose-elicited neuronal activity (cFos expression) in Dopaminergic neurons in the VTA. TH = tyrosine hydroxylase. Unpublished image.

Organization of taste responses in cortex revealed by 2 photon imaging

The gustatory cortex plays a key role in the generation and maintenance of taste-related behaviors. To gain insight into how information about taste quality and hedonics are organized in cortical neurons, we used 2 photon imaging to measure taste-evoked activity in large sets of cells labeled with the fluorescent calcium reporter GCaMP6 (Fletcher et al., 2017). This work is a collaboration with my departmental colleague Max Fletcher (hyperlink). Roughly 64% of all cells responded to only single taste qualities, whereas others were more broadly “tuned” (n=783 cells). Multivariate analysis of this data demonstrates that stimuli of different primary taste qualities (sweet, sour, salty and bitter) evoke distinct patterns of responses across the cortical neuronal population. Current studies extend on these findings, investigating taste responses in specifically labeled neuronal subtypes, as well as using awake imaging techniques to examine taste responses in behaving mice.

chart
Cortical 2P imaging of taste responses. A. GCaMP6 expression in cortical neurons in the gustatory cortex, which can be identified via thalamic input (mCherry label). B. Representative taste responses in 4 different neurons reveals heterogeneity in response. C. Cells with best responses to individual taste qualities are randomly distributed in cortical space.

Other Research

Another long-running interest in our lab is the study of the genetic underpinnings of oromotor function, especially fluid licking, in mice. We have conducted surveys of licking and ingestive microstructure with large panels of inbred and BXD recombinant inbred mice, and have identified loci on Chr 1 and 10 with major effects on lick rate (Boughter et al., 2012; St. John et al., 2017). Finally, I also collaborate with Faculty and Residents in the Department of Otolaryngology - Head and Neck Surgery, with recent projects using either animal models or human tissue.

Representative Publications

  • Fletcher ML, Ogg MC, Lu L, Ogg RJ, Boughter JD Jr. Overlapping Representation of Primary Tastes in a Defined Region of the Gustatory Cortex. J Neurosci. 2017 Aug 9;37(32):7595-7605. doi: 10.1523/JNEUROSCI.0649-17.2017. Epub 2017 Jul 3. PubMed PMID: 28674169; PubMed Central PMCID: PMC5551059.
  • Smith A, Kortebein S, Eid A, Boughter J, Cary N, Brooks J, Sebelik M. Comparing Cancellous Bone Volume of the Manubrium to Iliac Crest in Fresh Cadavers. Otolaryngol Head Neck Surg. 2017 Jul;157(1):36-41. doi: 10.1177/0194599817692961. Epub 2017 Feb 1. PubMed PMID: 28669310.
  • St John SJ, Lu L, Williams RW, Saputra J, Boughter JD Jr. Genetic control of oromotor phenotypes: A survey of licking and ingestive behaviors in highly diverse strains of mice. Physiol Behav. 2017 Aug 1;177:34-43. doi: 10.1016/j.physbeh.2017.04.007. Epub 2017 Apr 12. PubMed PMID: 28411104; PubMed Central PMCID: PMC5540359.
  • Shires C, Smith A, Lee J, Boughter J, Sebelik M. Classification system for lateral pharyngotomy: systematic study of anatomic exposure in a human cadaver model. Surg Radiol Anat. 2017 Sep;39(9):975-979. doi: 10.1007/s00276-017-1827-x. Epub 2017 Feb 27. PubMed PMID: 28243697.
  • Tokita K, Boughter JD Jr. Topographic organizations of taste-responsive neurons in the parabrachial nucleus of C57BL/6J mice: An electrophysiological mapping study. Neuroscience. 2016 Mar 1;316:151-66. doi: 10.1016/j.neuroscience.2015.12.030. Epub 2015 Dec 19. PubMed PMID: 26708748; PubMed Central PMCID: PMC4724509.
  • Rebecca Glatt A, St John SJ, Lu L, Boughter JD Jr. Temporal and qualitative dynamics of conditioned taste aversions in C57BL/6J and DBA/2J mice self-administering LiCl. Physiol Behav. 2016 Jan 1;153:97-108. doi: 10.1016/j.physbeh.2015.10.033. Epub 2015 Oct 31. PubMed PMID: 26524511.

View more references (pubmed link)