Merlau, P. R. | bioRxiv Science

bioRxiv2024

Behavioral screening of conserved RNA-binding proteins reveals CEY-1/YBX RNA-binding protein dysfunction leads to impairments in memory and cognition

RNA-binding proteins (RBPs) regulate translation and plasticity which are required for memory. RBP dysfunction has been linked to a range of neurological disorders where cognitive impairments are a key symptom. However, of the 2,000 RBPs in the human genome, many are uncharacterized with regards to neurological phenotypes. To address this, we used the model organism C. elegans to assess the role of 20 conserved RBPs in memory. We identified eight previously uncharacterized memory regulators, three of which are in the C. elegans Y-Box (CEY) RBP family. Of these, we determined that cey-1 is the closest ortholog to the mammalian Y-Box (YBX) RBPs. We found that CEY-1 is both necessary in the nervous system for memory ability and sufficient to increase memory. Leveraging human datasets, we found both copy number variation losses and single nucleotide variants in YBX1 and YBX3 in individuals with neurological symptoms. We identified one predicted deleterious YBX3 variant of unknown significance, p.Asn127Tyr, in two individuals with neurological symptoms. Introducing this variant into endogenous cey-1 locus caused memory deficits in the worm. We further generated two humanized worm lines expressing human YBX3 or YBX1 at the cey-1 locus to test evolutionary conservation of YBXs in memory and the potential functional significance of the p.Asn127Tyr variant. Both YBX1/3 can functionally replace cey-1, and introduction of p.Asn127Tyr into the humanized YBX3 locus caused memory deficits. Our study highlights the worm as a model to reveal memory regulators and identifies YBX dysfunction as a potential new source of rare neurological disease. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=66 SRC="FIGDIR/small/574402v2_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@c1e04forg.highwire.dtl.DTLVardef@6d82b9org.highwire.dtl.DTLVardef@1a15571org.highwire.dtl.DTLVardef@f0ad20_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2020

Simultaneous in vitro simulation of multiple antimicrobial agents with different elimination half-lives in a pre-clinical infection model

Combination therapy for treatment of multi-drug resistant bacterial infections is becoming increasingly common. In vitro testing of drug combinations under realistic pharmacokinetic conditions is needed before a corresponding combination is eventually put into clinical use. The current standard for in vitro simulation of the pharmacokinetics of two drugs with distinct elimination half-lives cannot be extended for combinations of three or more agents, posing a growing need. To address that need we develop a general method to design an in vitro model for simultaneous simulation of the kinetics of an arbitrary number of N drugs with different half-lives. The method developed entails two possible configurations: (a) An in-series configuration, which generalizes the standard two-drug design for N drugs and offers additional flexibility even for two drugs, and (b) an in-parallel configuration, which is new, and offers yet additional flexibility over the in-series configuration. Corresponding design equations for sizing and operation of each configuration are rigorously developed for immediate use by experimenters. These equations were used for experimental verification using a combination of three antibiotics with distinctly different half-lives (meropenem, ceftazidime, and levofloxacin). While experimental verification involved antibiotics, the method is applicable to any anti-infective or anti-cancer drugs with distinct elimination pharmacokinetics. With increasing importance of in vitro simulation of the kinetics of an arbitrary number of drugs in combination, the methods developed here are an important new tool for the design of such in vitro models.

pharmacology and toxicology↗