In our research we use the model organism C. elegans, a
free-living soil based roundworm. Dr. Portman's lab uses several
approaches, including a novel technique to sex-reverse the nervous
system of our worms, to study the above questions. Former students and
post-docs in the lab have investigated sex differences in olfaction and
locomotion. Currently, we are working on understanding a sex difference
in exploration. Males explore to a much greater extent than do
hermaphrodites in this species. We find that the difference in
exploration can be traced to a single gene product, expressed in a
single pair of sensory neurons in C. elegans hermaphrodites.
Forcing the expression of this gene in males, or sex reversing the
nervous system can lead to hermaphrodite-like behavior in male worms. We
are currently investigating the link between this gene and food
sensation as well as what kind of evolutionary advantage this sex
difference confers upon C. elegans males.
Additional projects that I am working on in Dr. Portman's lab, with
the help of two talented undergraduate students, Teigan Ruster and Andy
Spitzberg, include sex differences in neuropeptide signaling and sex
differences in the dauer alternate life stage decision. All of these
projects ultimately help us to understand how sex differences in the
brain are generated and regulated, what the physical substrates of the
differences are, and how such differences interact with environmental
stimuli to produce unique behavioral outputs and differential disease
Courses Offered (subject to change)
Basic Lab in Neurobiology
Lab in Cognitive Neuroscience
Neurochemical Foundations of Behavior
Biology of Mental Disorders
DA Ryan, RM Miller, KH Lee, S Neal, K Fagan, P Sengupta and DS Portman. Sex, age and hunger regulate behavioral prioritization through dynamic modulation of chemoreceptor expression. Curr Biol. 2014 Nov 3;24(21):2509-17.
Siehr MS, Koo PK, Sherlekar AL, Bian X, Bunkers MR, Miller RM, Portman DS, Lints R. Multiple doublesex-related genes specify critical cell fates in a C. elegans male neural circuit. Plos One. 2011;6(11):e26811.
Miller, RM and Portman, DS. Wnt-directed asymmetry of the bHLH factor LIN-32 controls cell fate specification in sensory rays of C. elegans. (2011) J. Neurosci. Sep 14;31(37):13281-91.
Zheng, B, Liao, Z, Locascio, JJ, Eklund, AC, Hauser, MA, Grunblatt, E, Moran, LB, Mandel, SA, Riederer, P, Miller, RM, Federoff, HJ, Wullner, U, Papapetropoulos, S, Youdim, MB, Cantuti-Castelvetri, I, Young, AB, Vance, JM, Davis, RL, Hedreen, JC, Adler, CH, Beach, TG, Graeber, MB, Middleton, FA, Rochet, J-C, and Scherzer, CR for the Global PD Gene Expression (GPEX) Consortium. (2010) PGC-1a, a potential therapeutic target for early intervention in Parkinson’s disease. Science Transl Med 2(52):52ra73.
Hurd, DD*, Miller, RM*, Nunez, LB, and Portman, DS. (2010) Specific a- and b-tubulin isotypes optimize the functions of sensory cilia in Caenorhabditis elegans. Genetics 185(3):883-96.
Miller, RM and Portman, DS. (2010) A latent capacity of the C. elegans polycystins to disrupt sensory transduction is repressed by the single-pass ciliary membrane protein CWP-5. Dis Model Mech. 3(7-8):441-50.
Miller, RM and Federoff, HJ. (2008) Isoform specific effects of Apo E on HSV immediate early gene expression and establishment of latency. Neurobiol. Aging. 29(1):71-77.
Miller, RM, Kiser, GL, Kaysser-Kranich, TM, Casaceli, C, Colla, E, Lee, MK, Palaniappan, C, and Federoff, HJ. (2007) Wild-type and mutant a-synuclein induce a multi-component gene expression profile consistent with shared pathophysiology in different transgenic mouse models of PD. Exp. Neurol. 204(1):421-432.
Miller, RM, Kiser, GL, Kaysser-Kranich, TM, Sendera, TJ, Palaniappan, C, and Federoff, HJ. (2006) Robust dysregulation of gene expression in substantia nigra and striatum in Parkinson’s disease. Neurobiol. Dis. 21(2):305-313.
Miller, RM, Chen, LL, Kiser, GL, Giesler, TL, Kaysser-Kranich, TM, Palaniappan, C, and Federoff, HJ. (2005) Temporal evolution of mouse striatal gene expression following MPTP injury. Neurobiol. Aging. 26(5):765-775.
Miller, RM, Callahan, LM, Kiser, GL, Casaceli, C, Chen L, Chui B, Kaysser-Kranich, TM, Sendera, TJ, Palaniappan, C, and Federoff, HJ. (2004) Dysregulation of gene expression in the MPTP-treated mouse substantia nigra. J Neurosci. 24(34):7445-7454.