Biology subjects

Zheng, K.

Publications and source records attributed to Zheng, K..

At least 19 recordsLinked to original sources

bioRxiv2026

ANO6 Scaffolds ER Mitochondria Contacts to Govern Spatial Lipid Compartmentalization and Ferroptosis Evasion in Chemoresistant Breast Cancer

Background: Metabolic glycerophospholipid remodeling promotes tumor persistence under neoadjuvant chemotherapy in breast cancer; however, how resistant cells evade lipotoxicity from accumulating peroxidizable lipids presents an intriguing metabolic conundrum. The underlying organelle-level spatial mechanisms remain poorly defined. Methods: Integrated multi-omic profiling of paired pre- and post-NAC clinical specimens was performed. Engineered ANO6 models (wild-type, knockout, and conformational mutants) were characterized using subcellular lipidomics of purified mitochondria-associated ER membranes (MAMs), electron microscopy, in situ proximity ligation assays, and preclinical xenograft models. Results: Chemoresistant lesions exhibited marked ANO6 upregulation and polyunsaturated phospholipid (PUFA-PL) accumulation without enhanced apoptosis. Beyond its canonical role as a plasma membrane scramblase, ANO6 operates as an organelle contact scaffold at MAMs, leveraging its conformational activation to coordinate inter-organellar tethering. ANO6 directly recruits vimentin (VIM) and VAPB to assemble a VIM-ANO6-VAPB-PTPIP51 tethering platform, structurally bridging intermediate filaments to organelle contact sites. This complex tightens ER-mitochondria coupling, establishing a specialized structural platform that routes and sequesters peroxidizable lipids into protective cytoplasmic lipid droplets, thereby shielding functional membrane bilayers from ferroptotic peroxidation. Functional dissection revealed that the active scaffolding conformation (I612A) sustains MAMs integrity and lipid packaging, whereas scaffold deficiency (D703R) compromises contact architecture. Pharmacologically perturbing this platform with niclosamide destabilized lipid sequestration, selectively resensitizing chemoresistant cells to synthetic lethal ferroptosis in vitro and in vivo. Conclusions: ANO6-mediated contact scaffolding governs spatial lipid compartmentalization, establishing the ANO6-MAMs structural axis as a potential target to exploit lipid metabolic vulnerabilities in refractory breast cancer.

cancer biology↗

bioRxiv2026

Probing Physical Intuition in Large Language Models through Partner-Dependent Mutation Prediction

Structure-guided mutation design requires relating a proposed substitution to its molecular environment to anticipate its effects. Existing evaluations of large language models (LLMs) in protein engineering emphasize sequence-based prediction or tool-integrated workflows, leaving unclear whether LLMs themselves can infer mutation effects from structural evidence without dedicated predictors. We evaluate physical intuition-qualitative reasoning that connects structural observations with molecular interaction principles-using a benchmark that tests the same substitution in the same protein across different binding partners, with predictions based on local atomic coordinates and no dedicated mutation-effect predictors. In the tested comparisons, the best-performing LLM achieved group accuracy comparable to the evaluated energy predictors and Biomni, an LLM-driven tool workflow, while the methods differed in their prediction patterns. Most evaluated LLMs achieved higher group accuracy for larger affinity improvements. Structural interventions support selective dependence on mutation-site and partner information, while assessable structural claims largely agree with the supplied coordinates. These findings support direct LLM structural reasoning as a basis for developing rational mutation-design tools that connect molecular observations with partner-specific effects.

bioinformatics↗

bioRxiv2026

Temporal Organization of Synaptic Input and Intrinsic Excitability Shape Direction Selectivity in the Developing Xenopus laevis Optic Tectum

A moving object passes through locations in visual space in a particular order. To distinguish opposite directions of motion, visual circuits must convert this temporal order into different direction selective neuronal responses. This ability emerges and is refined as visual circuits develop. In Xenopus laevis tadpoles, direction selectivity in the optic tectum sharpens over development. Companion work by Zheng et al (2026) shows that direction selectivity sharpens between stage 45 (approximately 6 to 7 days postfertilization), when the retinotectal circuit is undergoing rapid refinement, and stage 48 (approximately 10 to 16 days postfertilization), when the projection has completed one phase of refinement and visual acuity has improved. The same study shows that, over this period, both the excitatory synaptic input received by tectal neurons and the intrinsic properties of those neurons change. How these synaptic and intrinsic changes work together to produce a sharpening of direction selectivity unclear. Here, we combined visually evoked excitatory postsynaptic current trains recorded at each stage with stage-specific single-compartment conductance-based models. These simulations reproduced the developmental increase in direction selectivity and reduction in spiking at stage 48. Changing intrinsic properties produced only modest changes in spike counts, while reassigning amplitudes among the original event times did not eliminate developmental sharpening. Together, these results suggest that the temporal organization of synaptic input carries much of the directional information, while intrinsic maturation lowers overall spike output, making the existing directional bias in the input more pronounced.

neuroscience↗

bioRxiv2026

Sensory experience drives glutamate spillover, presynaptic LTP and functional connectome remodeling in the barrel cortex

Information handling and storage by neural circuits is thought to involve dynamic changes in the synaptic connectome, yet how this process unfolds at the level of individual synapses in vivo remains unclear. We took advantage of a well-defined thalamocortical anatomical framework to monitor identifiable individual synapses in barrel cortex during rhythmic whisker stimulation (RWS). Multiplexed ratiometric readouts from genetically targeted optical sensors showed that RWS-induced long-term potentiation (LTP) increased glutamate release per action potential in RWS-responsive axons while recruiting previously silent thalamocortical connections. Fast high-resolution imaging revealed pronounced inter-synaptic glutamate transients and global extracellular GABA waves triggered by brief RWS. LTP induction had no detectable effect on the evoked GABA signal but further enhanced glutamate crosstalk beyond thalamocortical synapses. Strikingly, neural-network simulations suggest that such volume-transmitted excitatory signals can improve associative memory retrieval in sparsely connected networks. Together, these findings uncover key plasticity features of the cortical synaptic connectome and point to a potential computational consequence of glutamate spillover for brain circuit function.

neuroscience↗

bioRxiv2026

Prompting Beyond Pairs: Decoupled Semantic Supervision for Knowledge-Guided Multiplex Virtual Staining

Virtual staining provides a non-invasive alternative to fluorescence microscopy, yet existing deep learning approaches fundamentally rely on pixel-aligned, multiplexed fluorescence targets for supervision. This dependence on rigidly paired data limits scalability, constrains flexibility in generating diverse subcellular structures, and becomes impractical in data-scarce biological settings. In this work, we introduce a semantic supervision paradigm for virtual staining, demonstrating that domain-knowledge prompts can effectively replace conventional pixel-level supervision. Unlike existing methods constrained by rigidly paired multiplex targets, our framework leverages biological prompts to decouple structural guidance from image translation. This decoupling enables high-fidelity, independent synthesis of multiple subcellular structures using only single-channel data. To ensure high-fidelity generation under weak supervision, we integrate self-supervised representation learning to mitigate data scarcity and incorporate direct preference optimization to suppress structural artifacts. Evaluations on the JUMP benchmark demonstrate that our approach effectively balances flexibility and fidelity, outperforming supervised baselines with a 43.3 % reduction in Average FID and an Average PCC of 0.912, while exhibiting high robustness in channel-deficient scenarios. Furthermore, the model generalizes across four in-house datasets to successfully multiplex six subcellular structures, overcoming the physical constraints of conventional fluorescent staining.

bioengineering↗

bioRxiv2026

Homeostatic control of stem cell activity during intestinal regeneration.

Stem cells proliferate rapidly to maintain fast tissue turnover during regeneration. However, the feedback mechanisms in stem cells that prevent hyperproliferation remain unclear, and their dysregulation can lead to organ failure and cancer. Here, we identified nuclear factor-Y (NF-Y) as the transcriptional repressors to maintain the stem cell quiescence during intestinal homeostasis. We found that NF-Y negatively regulates intestinal stem cell (ISC) proliferation through preferentially occupying the promoters of EGFR signaling pathway components Egfr/Mkp3/Raf/Ras/pointed, via the action of histone acetyltransferase Nejire (Nej)/p300 dependent transcription regulation. While the loss of NF-Y enhances ISC proliferation, cell death and sensitivity to stress and tumor induced mortality. Moreover, NF-Y acts together with Nej to restrict Egfr expression and suppress ISC hyperproliferation. Together, these results demonstrate NF-Y acts with Nej serve as a key negative feedback module to orchestrate transcription initiation and termination of growth signaling in the control of stem cell activity in homeostatic and disease conditions.

cell biology↗

bioRxiv2026

Fibulin-2 transduces a matrix-to-metabolism signal in kidney fibrosis

Fibrotic extracellular matrix (ECM) is not merely a structural scaffold but an instructive signaling interface that shapes epithelial cell state. However, the molecular cues by which matrix remodeling controls tubular metabolism during kidney fibrosis remain poorly defined. Here, we identify Fibulin-2 (FBLN2) as a fibroblast-derived matrix cue that transduces fibrotic ECM remodeling into tubular mitochondrial metabolic reprogramming. Using fibroblast-selective deletion of Smoothened (Smo) across distinct fibroblast subpopulations, we found that loss of fibroblast Smo preserved kidney function and attenuated fibrosis in mouse models of chronic kidney injury. Multi-omics profiling revealed coordinated remodeling of the fibrotic matrisome, highlighted by suppression of FBLN2, an ECM glycoprotein genetically linked to kidney function in humans. Mechanistically, FBLN2 engaged EGFR in tubular epithelial cells and activated EGFR-AKT signaling in a non-canonical ligand-like manner. This signaling axis suppressed acetyl-CoA acetyltransferase 1 (ACAT1), a mitochondrial regulator of fatty acid oxidation and amino acid metabolism. Disruption of fibroblast Smo-FBLN2 signaling restored ACAT1-dependent oxidative metabolism and reduced tubular fibrotic activation. Spatial lipidomics revealed compartment-specific lipid remodeling associated with altered mitochondrial fatty acid metabolism, including acylcarnitine and phospholipid changes linked to reduced fibrotic injury. Together, these findings define a Fibulin-2-EGFR-ACAT1 matrix-to-metabolism signaling axis that couples fibrotic ECM remodeling to tubular mitochondrial metabolism during kidney fibrosis.

cell biology↗

bioRxiv2026

Polychrome activity profiling distinguishes Cys proteases and their isoforms in plants

Activity-based profiling with fluorescent probes is a powerful tool for the functional characterization of whole enzyme classes in crude proteomes. Here, we discovered that probe cocktails consisting of the E-64 warhead carrying different fluorophores via short linkers distinguishes the labeling of papain-like cysteine proteases and their isoforms because of their differential affinity to these probes. This causes polychrome labeling with specific apparent colors for different protease families and isoforms. Polychrome labeling revealed differential labeling of isoforms of RD21-like proteases carrying C-terminal granulin domains. Molecular modeling of the RD21 isoforms revealed that the C-terminal granulin may create a fluorophore-binding pocket with the substrate-binding groove, implying that the granulin domain influences substrate selectivity. The concept of polychrome labeling may be widely applicable to other chemical probes for the characterization of protein families in all kingdoms of life.

Plant Biology↗

bioRxiv2026

NbRD21 protease controls receptor kinase homeostasis in Nicotiana benthamiana

RD21-like proteases are papain-like cysteine proteases with a C-terminal granulin domain that are abundant and ubiquitous in angiosperms and have often been implicated in immunity. We previously found that the activity of RD21 in Nicotiana benthamiana (NbRD21) is suppressed during infection with Pseudomonas syringae. Here, we studied the role of NbRD21 in immunity and proteome processing. NbRD21 was disrupted by genome editing and rd21 mutants were subjected to disease assays and shot-gun proteomics. Dipeptide substrate zLR-AMC was used in protease assays and agroinfiltration was used to transiently express NbRD21 and candidate substrates. Genome edited lines lacking NbRD21 develop normally but have drastically reduced zLRase activity and are significantly more susceptible to P. syringae. Shot gun proteomics revealed an increased accumulation of [~]20 diverse receptor-like kinases (RLKs) in untreated rd21 knockout lines, but their transcript levels are unaltered when compared to wild-type plants. 35S-driven GFP-tagged RLKs accumulate more upon transient expression in rd21 plants than in wild- type plants. These data indicate that NbRD21 post-translationally controls RLK homeostasis, either by directly degrading RLKs, or indirectly by regulating endocytic RLK recycling.

plant biology↗

bioRxiv2026

Targeting TPO/MPL Signaling to Mitigate JAK2V617F-driven Cardiac Microvascular Disease

BackgroundIndividuals with JAK2V617F-mutant myeloproliferative neoplasms or clonal hematopoiesis of indeterminate potential have a markedly increased risk of cardiovascular disease, yet the mechanisms by which mutant blood cells drive vascular and cardiac dysfunction remain incompletely understood. Although the thrombopoietin (TPO) receptor MPL is central to hematopoiesis and is expressed in vascular endothelial cells (ECs), its role in JAK2V617F-associated cardiovascular complications is unknown. Methods and ResultsWe generated chimeric mice with JAK2V617F-mutant blood cells and wild-type endothelium by bone marrow transplantation and challenged them with a high-fat/high-cholesterol diet to model cardiometabolic stress. These mice developed a distinct cardiovascular phenotype characterized by microvascular disease, increased left ventricular mass, and relatively preserved left ventricular ejection fraction. Histological analysis revealed coronary arteriole stenosis, perivascular fibrosis, reduced microvascular density, and endocardial injury, without evidence of epicardial coronary stenosis or myocardium infarction. Single-cell RNA sequencing revealed activation of inflammatory, stress-response, and endothelial-to-mesenchymal transition gene signatures in ECs, most prominently within the endocardial ECs. Immunohistochemistry identified MPL expression predominantly in endocardial ECs. TPO/MPL signaling was upregulated in endocardial ECs in mice with JAK2V617F-mutant hematopoiesis, and treatment with an anti-MPL neutralizing antibody markedly improved cardiac pathology, restored endocardial integrity, and increased coronary microvascular density despite persistent systemic inflammation. ConclusionsJAK2V617F-mutant hematopoiesis induces coronary microvascular dysfunction. Endocardial ECs represent a key cellular target under cardiometabolic stress, and endocardial MPL signaling constitutes a potential targetable pathway in JAK2V617F-associated cardiovascular disease. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=122 SRC="FIGDIR/small/715884v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@15dcebdorg.highwire.dtl.DTLVardef@1b00a2eorg.highwire.dtl.DTLVardef@6c6f98org.highwire.dtl.DTLVardef@1128f75_HPS_FORMAT_FIGEXP M_FIG C_FIG Key PointsO_LIJAK2V617F-mutant hematopoiesis induces cardiac microvascular disease C_LIO_LIMPL is expressed in endocardial ECs and MPL inhibition restores endocardial integrity and improves cardiac microvascular function C_LI

cell biology↗

bioRxiv2026

A hidden T-DNA-linked inversion-duplication causes a pronounced light-dependent phenotype in Arabidopsis

T-DNA insertion mutants are widely used to disrupt genes and infer their functions, yet the insertions can also trigger unintended genomic changes that confound phenotypic interpretation. Here, we used T-DNA insertion mutants affecting the major mitochondrial malate dehydrogenase (MDH1) and the heterodimeric NAD-dependent malic enzymes (ME1 and ME2) to examine their functional coordination across photoperiods and irradiance regimes. Under short days, especially at low light intensity, mdh1xme2 mutants were markedly smaller than wild type and, unexpectedly, than the mdh1xme1xme2 triple mutant, and they showed a more pronounced reduction in photosynthetic capacity. ME1 was undetectable in mdh1xme2, implying that the double and triple mutants effectively lack heterodimeric ME and should therefore behave similarly, contrary to what we observed. Whole-genome analysis resolved this discrepancy by revealing that the MDH1 T-DNA insertion in mdh1xme2 is accompanied by a major rearrangement, a 137-kbp duplication downstream of the insertion site, which was absent in the mdh1xme1xme2 triple mutant. This duplication increased gene dosage and elevated transcript abundance across the duplicated interval, while proteomics detected 5 of the 38 encoded proteins, including PEPC1. mdh1xme2 accumulated oxaloacetate-derived amino acids and displayed an altered carbon/nitrogen balance, making PEPC1 a plausible contributor to the exacerbated mdh1xme2 phenotype. Together, our data indicate that a T-DNA-linked structural variant can amplify expression of dozens of genes and intensify phenotypes at specific conditions, thereby affecting the interpretation of genotype-phenotype relationships. Because Agrobacterium-mediated DNA transfer also underpins many genome-editing workflows, our findings argue that structural validation around insertion/editing loci should be considered essential when interpreting T-DNA-derived plant lines.

plant biology↗

bioRxiv2026

Mitochondrial malate metabolism acts as a control hub for photosynthesis and carbon-nitrogen balance in Arabidopsis

Malate is a central metabolite in plant energy metabolism and biosynthesis and serves as a major carrier of carbon and reducing equivalents between chloroplasts, the cytosol, and mitochondria. However, how individual malate-converting systems contribute to physiology in specific subcellular compartments remains incompletely understood. Here, we investigated the impact of combined loss of mitochondrial malate dehydrogenase (MDH) and NAD-dependent malic enzyme (NAD-ME) activity in Arabidopsis thaliana by integrating reverse genetics, physiological analyses, transcriptomics, quantitative proteomics, and metabolite profiling. Specifically, we generated triple mutants (mdh1xme1xme2) lacking the predominant mitochondrial isoform MDH1 together with both NAD-ME subunits, thereby reducing overall mitochondrial malate conversion capacity. By growing plants under contrasting photoperiod and irradiance regimes to vary photosynthetic demand on malate-linked fluxes, we uncovered a conditional phenotype that was most pronounced under short-day/low-light conditions. Under these conditions, mdh1xme1xme2 exhibited impaired growth and photosynthetic performance, accompanied by cytosolic redox imbalance and altered chloroplast ultrastructure. Transcriptomic profiling revealed that low light unmasks a dawn-phase bottleneck in establishing photosynthetic and redox homeostasis. Consistent with this, the low-light plastid proteome revealed a reallocation away from chloroplast translation and photosynthetic capacity toward proteome maintenance, photoprotection/repair, and iron/ROS management, consistent with a protective acclimation state that nevertheless constrains carbon gain under energy limitation. Low light also triggered C/N imbalance and ammonium accumulation in the mutants. In contrast, increasing irradiance or extending the photoperiod largely alleviated these defects. Together, our results identified mitochondrial malate conversion capacity as a key control point coupling respiratory energy supply and redox homeostasis to photosynthetic metabolism when photosynthetic energy input is limiting.

plant biology↗

bioRxiv2026

Macrophage Iron Metabolism in Allografts and Tumors

Macrophages are present at high frequencies in transplanted organs and solid tumors. These infiltrating macrophages are highly tuned by tissue niche signals. However, the underlying mechanisms that orchestrate the activation of distinct macrophage populations remain unclear. Here, using heart transplantation and tumor implantation models, we found that macrophages in cardiac allografts exhibited higher intracellular iron (Fe2+) level and higher expression of the iron transporter SLC11A1 than those in the solid tumors. In mice, the myeloid-specific deletion of Slc11a1 alleviated the proinflammatory state of macrophages and cardiac allografts rejection. Together, our findings identify SLC11A1 as a new player in immune response regulation, implicating SLC11A1 as a therapeutic target for both allograft and tumor rejection. This preprint reports initial findings; additional experiments are ongoing and will be included in a future full manuscript.

immunology↗

bioRxiv2026

Monitoring Gene Expression in Retina with Synthetic Serum Markers

Gene expression underlies retinal development, function, and pathogenesis. However, monitoring retinal gene expression in vivo is challenging. In this study, we apply synthetic serum markers, called Released Markers of Activity, or RMAs, to quantify gene expression in an intact retina through a simple blood test. We show that RMAs can quantify transduction of multiple retinal cell-types and monitor cell implantation or cell loss. We found RMAs are sensitive enough to measure transduction of rare cell populations, such as retinal ganglion cells and could detect transplantation of as few as 100 stem cells. Expression of RMAs showed no evidence of cell loss or immune activation in the retina. Overall, these findings demonstrate that RMAs are highly sensitive, tissue non-destructive gene expression reporters that can continuously track gene delivery and cell survival in intact retina through a simple blood test.

bioengineering↗

bioRxiv2025

De novo design of protein binders that target DELE1 to inhibit the mitochondrial stress response

Mitochondrial stress activates the integrated stress response (ISR) through the mitochondrial protein DELE1, which relays stress signals to the cytosolic kinase HRI to induce ATF4. Dysregulation of DELE1-mediated signaling has been implicated in pathological conditions, yet molecular strategies to modulate DELE1 remain unavailable. Here, we report de novo designed proteins that bind DELE1, block its oligomerization, and inhibit DELE1-mediated ISR activation. Several designs form stable complexes with DELE1 and disrupt its oligomerization in vitro while preserving DELE1s ability to bind HRI. In cells, these designs suppress ATF4 induction during mitochondrial stress and impair the recovery of elongated mitochondrial morphology following transient insult. Crystal structure of a representative binder, together with structural modeling and targeted mutagenesis, confirm that the designed proteins engage a critical interface required for DELE1 oligomerization. These findings establish DELE1 as a druggable target and demonstrate that de novo designed proteins offer precise tools to modulate this pathway, providing a foundation for future therapeutic exploration. SIGNIFICANCEMitochondrial stress activates the integrated stress response through the signaling protein DELE1, but no molecular tools have been available to directly target DELE1 and selectively modulate this pathway. We developed de novo designed protein binders that recognize a critical oligomerization interface in DELE1, disrupt its assembly, and suppress mitochondrial stress-induced ISR activation in cells. These binders also impair recovery of mitochondrial network morphology following transient stress, linking DELE1 assembly to adaptive remodeling. Our study establishes DELE1 as a tractable and druggable target in mitochondrial stress signaling and demonstrates that de novo protein design can generate precise modulators of intracellular stress-response pathways.

biochemistry↗

bioRxiv2025

Ecology of hydrocarbon degradation in widespread viruses

Hydrocarbons are vital for energy production and lead to serious environmental issues due to pollution. Microorganisms largely drive the production and degradation of hydrocarbons, yet little is known about viral contributions to hydrocarbon degradation. Here we identified 786 viral contigs from IMG/VR(v4), encoding five aerobic (alkB, ladA, almA, ndoB and dszC) and three anaerobic (bssA, ebdA and abcA) hydrocarbon-degrading genes (HDGs). vOTUs encoding HDGs span 26 distinct viral families, including 249 are mainly associated with host-associated environment and 463 are derived from aquatic habitat, respectively, implying that these viruses are broadly engaged in hydrocarbon-degradation processes across the entire biosphere. alkB (35%) and almA (28%) was tended to be encoded by Schizomimiviridae, bssA was tended to be encoded by T5-like bacteriophages (29%) and SPO1-like bacteriophages (22%), suggesting that the carriage of HDGs by viruses exhibits taxonomic specificity. With respect to host associations, Pseudomonadota and Bacillota constitute the two main potential host lineages, associated with 268 and 71 vOTUs, respectively. The profiling of ecological footprint reveals that viruses contribute a total of up to 30% gene abundance and 32% transcribing activity to hydrocarbon degradation in the global ocean. This study systematically revealed the distribution, diversity, virus-host correlation and activity of virus-encoded HDGs, underscoring the significant role of viruses in hydrocarbon metabolism on a global scale.

ecology↗

bioRxiv2025

Polyphenol oxidase mutant Nicotiana benthamiana plants increase yield and purity of recombinant proteins and enable studies of proteins in their native state.

Agroinfiltration of Nicotiana benthamiana is widely used for recombinant protein production in plant science and molecular pharming, but enzymatic browning and native protein crosslinking during extraction may limit protein integrity and purification efficiency. We generated genome-edited N. benthamiana lines lacking two polyphenol oxidases (PPOs) and analysed protein integrity, enzymatic activity profiles, and recombinant protein purification under non-denaturing extraction conditions. PPO-deficient plants showed reduced browning and native protein crosslinking, preserved endogenous proteins at their predicted molecular weights, displayed increased detectable enzyme activities, and achieved a significantly higher recovery and improved purity of a transiently expressed recombinant protein. These findings identify PPO-mediated oxidation as a major bottleneck during protein extraction and demonstrate that PPO depletion enhances recombinant protein purification while preserving native protein integrity.

plant biology↗

bioRxiv2025

Episodic-Like Memory in a Simulation of Cuttlefish Behavior

Episodic memory involves remembering the what, when, and where components of an event. It has been observed in humans, other vertebrates, and cephalopods. In clever behavioral experiments, cuttlefish have been shown to have episodic-like memory, where they demonstrate the ability to remember when and where a preferred food source will appear. The present work replicates this behavior with a parsimonious model of episodic memory. To further test this model and explore episodic-like memory, we introduce a predator-prey scenario in which the agent must remember what creatures (e.g. predator, desirable prey, or less desirable prey) appear at a given time and region of the model environment. This simulates similar situations that cephalopods face in the wild. They will typically hide when predators are in the area, and hunt for prey when available. When the memory model is queried for an action (e.g., hunt or hide), the cuttlefish agent hunts for preferred food, like shrimp, when available, and hides at other times when a predator appears. When the memory model is queried for a place, the cuttlefish agent acts opportunistically, seeking less-preferred food (e.g., crabs) if it is located farther from a predator. These differences show how behavior can be altered depending on how memory is accessed. Querying the model over time might mimic mental time travel, a hallmark of episodic memory. Although developed with cephalopods in mind, the model shares similarities with the hippocampal indexing theory and captures aspects of vertebrate episodic memory. This suggests that the underlying mechanisms supporting episodic-like behavior in the present model may not be unique to cephalopods.

animal behavior and cognition↗