Scott LL et al. (2018) Neuropsychopharmacology "Small molecule modulators of 2R/Tmem97 reduce alcohol withdrawal-induced behaviors."

Ferragud A, Scott LL, Satarasinghe PN, Shen A, Hodges TR, Friese KM, Prakash BA, Sabino V, Martin SF, Pierce JT, Wood MD, Sahn JJ, Yen RC, Shi T

[Neuropsychopharmacology, 2018]

Repeated cycles of intoxication and withdrawal enhance the negative reinforcing properties of alcohol and lead to neuroadaptations that underlie withdrawal symptoms driving alcohol dependence. Pharmacotherapies that target these neuroadaptations may help break the cycle of dependence. The sigma-1 receptor (1R) subtype has attracted interest as a possible modulator of the rewarding and reinforcing effects of alcohol. However, whether the sigma-2 receptor, recently cloned and identified as transmembrane protein 97 (2R/TMEM97), plays a role in alcohol-related behaviors is currently unknown. Using a Caenorhabditis elegans model, we identified two novel, selective 2R/Tmem97 modulators that reduce alcohol withdrawal behavior via an ortholog of 2R/TMEM97. We then show that one of these compounds blunted withdrawal-induced excessive alcohol drinking in a well-established rodent model of alcohol dependence. These discoveries provide the first evidence that 2R/TMEM97 is involved in alcohol withdrawal behaviors and that this receptor is a potential new target for treating alcohol use disorder.

Scott, L.L. et al. (2015) International Worm Meeting "A novel target protects against APP-induced age-related neurodegeneration ."

Mondal, S., Pierce-Shimomura, J., Ben-Yakar, A., Sahn, J., Satarasinghe, P., Zuniga, G., Scott, L.L., Martin, S., Iyer, S.V.

[International Worm Meeting, 2015]

Alzheimer's disease (AD) is the sixth leading cause of death in the US, affecting more than 5 million people with sadly no treatment in sight. AD is a neurodegenerative disorder characterized by protein aggregates and selective degeneration of cholinergic neurons. The sigma receptor family has been implicated as mediators of cell death, though a specific role for the sigma receptor 2/progesterone receptor membrane component 1 (Sig2R/PGRMC1) in neurodegeneration has not been shown. To test for a neuroprotective role of Sig2R/PGRMC1, we used a C. elegans model of neurodegeneration with a single copy insertion of the human Amyloid Precursor Protein (APP) gene. This SC_APP strain displays progressive, age-dependent changes in APP protein regulation in specific cholinergic neurons that subsequently die. Moreover, Sig2R/PGRMC1, or VEM-1, has a highly conserved sequence and function in this animal. We found that Sig2R/PGRMC1 null alleles significantly reduced the selective degeneration of cholinergic neurons in older adult SC_APP animals but had little effect on baseline neurodegeneration in control animals. To find molecules that might influence the Sig2R/PGRMC1 pathway we screened novel compounds for the ability to reduce neurodegeneration. We found two compounds that increase neurodegeneration in both the SC_APP model and control strains. More importantly, we found two compounds that decrease neurodegeneration in the SC_APP model. The latter compounds do not further reduce neurodegeneration when coupled with Sig2R/PGRMC1-directed knockdown suggesting that these compounds act in a Sig2R/PGRMC1-mediated pathway. Together, our results indicate that Sig2R/PGRMC1 can be targeted to reduce neurodegeneration and that small molecules that bind to Sig2R/PGRMC1 may be developed into promising therapeutic leads for age-related neurodegenerative diseases. In order to accelerate the speed of drug screening in our SC_APP model we are currently developing an automated large scale microfluidic imaging platform in a high-throughput manner.

Scott LL et al. (2017) Genetics "Behavioral Deficits Following Withdrawal from Chronic Ethanol Are Influenced by SLO Channel Function in Caenorhabditis elegans."

Pierce JT, Scott LL, Ordemann GJ, Nordquist SK, Bannai D, Yen RC, Davis SJ

[Genetics, 2017]

Symptoms of withdrawal from chronic alcohol use are a driving force for relapse in alcohol dependence. Thus, uncovering molecular targets to lessen their severity is key to breaking the cycle of dependence. Using the nematode Caenorhabditis elegans, we tested whether one highly conserved ethanol target, the large-conductance, calcium-activated potassium channel (known as the BK channel or Slo1), modulates ethanol withdrawal. Consistent with a previous report, we found that C. elegans displays withdrawal-related behavioral impairments after cessation of chronic ethanol exposure. We found that the degree of impairment is exacerbated in worms lacking the worm BK channel, SLO-1, and is reduced by selective rescue of this channel in the nervous system. Enhanced SLO-1 function, via gain-of-function mutation or overexpression, also dramatically reduced behavioral impairment during withdrawal. Consistent with these results, we found that chronic ethanol exposure decreased SLO-1 expression in a subset of neurons. In addition, we found that the function of a distinct, conserved Slo family channel, SLO-2, showed an inverse relationship to withdrawal behavior, and this influence depended on SLO-1 function. Together, our findings show that modulation of either Slo family ion channel bidirectionally regulates withdrawal behaviors in worm, supporting further exploration of the Slo family as targets for normalizing behaviors during alcohol withdrawal.

Scott LL et al. (2017) Sci Rep "A novel BK channel-targeted peptide suppresses sound evoked activity in the mouse inferior colliculus."

Brecht EJ, Scott LL, Mihic SJ, Walton JP, Wu NS, Iyer S, Pierce J, Philpo A, Aldrich RW

[Sci Rep, 2017]

Large conductance calcium-activated (BK) channels are broadly expressed in neurons and muscle where they modulate cellular activity. Decades of research support an interest in pharmaceutical applications for modulating BK channel function. Here we report a novel BK channel-targeted peptide with functional activity in vitro and in vivo. This 9-amino acid peptide, LS3, has a unique action, suppressing channel gating rather than blocking the pore of heterologously expressed human BK channels. With an IC50 in the high picomolar range, the apparent affinity is higher than known high affinity BK channel toxins. LS3 suppresses locomotor activity via a BK channel-specific mechanism in wild-type or BK channel-humanized Caenorhabditis elegans. Topical application on the dural surface of the auditory midbrain in mouse suppresses sound evoked neural activity, similar to a well-characterized pore blocker of the BK channel. Moreover, this novel ion channel-targeted peptide rapidly crosses the BBB after systemic delivery to modulate auditory processing. Thus, a potent BK channel peptide modulator is open to neurological applications, such as preventing audiogenic seizures that originate in the auditory midbrain.

Scott LL et al. (2018) J Pharmacol Exp Ther "A novel peptide restricts ethanol modulation of the BK channel in vitro and in vivo."

Aldrich RW, Avalos MN, Nguyen TT, Prakash BA, Mihic SJ, Shi T, Pierce JT, Philpo AE, Scott LL, Iyer S, Wu NS

[J Pharmacol Exp Ther, 2018]

Alcohol is a widely used and abused substance. A major unresolved issue in the alcohol research field is determining which of the many alcohol target proteins identified to date is responsible for shaping each specific alcohol-related behavior. The large-conductance, calcium- and voltage-activated potassium channel, or BK channel, is a conserved target of ethanol. Genetic manipulation of the highly conserved BK channel influences alcohol-related behaviors across phylogenetically diverse species that include worm, fly, mouse, and man. A pharmacological tool that prevents alcohol's action at a single target, like the BK channel, would complement genetic approaches in the quest to define the behavioral consequences of alcohol at each target. To identify agents that specifically modulate the action of ethanol at the BK channel, we executed a high-throughput phagemid-display screen in combination with a <i>C. elegans</i> behavioral genetics assay. This screen selected a novel nonapeptide, LS10, that moderated acute ethanol intoxication in a BK channel-humanized <i>C. elegans</i> strain without altering basal behavior. LS10's action <i>in vivo</i> was dependent upon BK channel functional activity. Single-channel electrophysiological recordings <i>in vitro</i> showed that pre-incubation with a sub-micromolar concentration of LS10 restricted ethanol-induced changes in human BK channel gating. In contrast, no substantial changes in basal human BK channel function were observed after LS10 application. The LS10 peptide provides a proof of concept that a combined phagemid-display/behavioral genetics screening approach can provide novel tools for understanding the action of alcohol at the BK channel and how this, in turn, exerts influence over CNS function.

Zhao C et al. (1993) Worm Breeder's Gazette "Cloning of the lin-32 Gene"

Emmons SW, Zhao C

[Worm Breeder's Gazette, 1993]

Cloning of the lin-32 gene Connie Zhao and Scott W. Emmons, Department of Molecular Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461

Townsend SR et al. (1994) Worm Breeder's Gazette "C. elegans Molecular Genetics and Long PCR."

Finelli AL, Savage C, Xie T, Padgett RW, Townsend SR

[Worm Breeder's Gazette, 1994]

C. elegans Molecular Genetics and Long PCR Scott R. Townsend, Cathy Savage, Alyce L. Finelli, Ting Xie, and Richard W. Padgett, Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08855

Emmons SW et al. (1994) Worm Breeder's Gazette "Strain Names for non-C. elegans Species."

Emmons SW, Fitch DHA, Leroi AM

[Worm Breeder's Gazette, 1994]

Strain names for non-C. elegans species Scott W. Emmonst, Armand Leroit, and David Fitch, Department of Molecular Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, Department of Biology, New York University, RmlOO9 Main Bldg., Washington Square, New York, NY 10003

Vrbanac A et al. (2017) Cell Host Microbe "An Elegan(t) Screen for Drug-Microbe Interactions."

Morton JT, Debelius JW, Knight R, Jiang L, Dorrestein P, Vrbanac A

[Cell Host Microbe, 2017]

Microbes affect drug responses, but mechanisms remain elusive. Two papers in Cell exploit C.elegans to infer anticancer drug mechanisms. Through high-throughput screens of drug-microbe-host interactions, Garcia-Gonzalez etal. (2017) and Scott etal. (2017) determine that bacterial metabolism underpins fluoropyrimidine cytotoxicity, providing a paradigm for unraveling bacterial mechanisms in drug metabolism.

Greenwald IS et al. (1983) Worm Breeder's Gazette "Tc1 polymorphisms on the right arm of LGIII."

Greenwald IS, Hodgkin JA

[Worm Breeder's Gazette, 1983]

As starting points for the molecular cloning of lin-12 III and tra-1 III, we have identified several Tc1 polymorphisms linked to these genes. Genomic DNA was prepared from appropriate Bristol/Bergerac hybrid strains, cut with EcoRI, and probed with Tc1 (kindly provided by Scott Emmons). Our data are summarized in the maps below, which give the approximate map locations and EcoRI fragment sizes of the Bergerac-specific Tc1's. [See Figure 1]