Biology subjects

Cho, P.

Publications and source records attributed to Cho, P..

5 recordsLinked to original sources

bioRxiv2026

Parallel processing chains span cytoarchitectures to organize association cortex

Task fMRI1 and electrophysiology2 have revealed distributed, linked cortical patches with shared category preferences (e.g., faces, objects, places)1,3-5, smaller than cytoarchitectonic areas. Resting-state functional connectivity (RSFC) similarly showed that somato-cognitive action network (SCAN) nodes interleave with effectors (foot, hand, mouth), subdividing the precentral gyrus6. Here, using multiple precision functional mapping (PFM) modalities (RSFC, task, lags), we discovered that most of association cortex is organized like face processing and SCAN, with small, discrete patches interconnected into chains. Such patch-chains densely tile prefrontal cortex but are largely absent from primary cortex. Cortico-striatal connectivity is organized such that patches of the same chain connect to the same striatal location. Within chains, infra-slow fMRI signals are ordered in time. RSFC-defined chains align with task fMRI localizers (e.g., visual, motor, pain). Chains are absent at birth and emerge in the first year of life, suggesting their formation is at least partially experience-driven. Cytoarchitectonic areas are subdivided by patches, and patches in the same chain are distributed across different cytoarchitectures. Chains represent parallel ordered processing streams that are separated by information domain and behavioral goals, not cytoarchitectonics. Functional subdivision of architectonics into smaller patches, interlinked to form cross-architecture chains, enable greater parallelization and flexible specialization of processing.

neuroscience↗

bioRxiv2025

Evidence for hierarchical representations of written and spoken words from an open-science human neuroimaging dataset

Reading and speech recognition rely on multi-level processing that builds from basic visual or sound features to complete word representations, yet details of these processing hierarchies (in particular those for spoken words) are still poorly understood. We re-analyzed the functional magnetic resonance imaging (fMRI) data provided in the Mother Of all Unification Studies (MOUS) open-science dataset by using parametric regressions of word frequency and sublexical unit (bigram or syllable) frequency during reading and speech listening tasks in order to elucidate lexical processing hierarchies in the visual and auditory modalities. We first validated our approach in the written word domain, where the technique identified significant correlations for word frequency in the left mid-fusiform cortex (at the location of the Visual Word Form Area) with a left occipital region tracking bigram frequency, compatible with prior reports. During listening, low-frequency spoken words elicited greater responses in a left mid-superior temporal region consistent with the recently-described Auditory Word Form Area (AWFA), while a more posterior region of the superior temporal gyrus was sensitive to syllable frequency. Activation in the left inferior frontal gyrus correlated with both written and spoken word frequency. These findings demonstrate parallel hierarchical organizations in the anteroventral visual and auditory streams, with modality-specific lexica and upstream sublexical representations that converge in higher-order language areas.

neuroscience↗

bioRxiv2025

A pan-generic marker panel for apples to enable genetic research and breeding across Malus species

AbstractWild Malus species harbor untapped genetic diversity to advance apple breeding, particularly for disease resistance and stress tolerance. However, existing marker panels, developed mainly using Malus domestica accessions, introduce ascertainment bias and limit detecting rare variants in wild species. We developed and validated a medium-density and cost-effective pan-generic 3K apple DArTag panel optimized to capture genome-wide variation across the Malus genus. The panel was constructed using conserved, syntenic, and collinear genomic blocks identified within the core genome of 13 Malus accessions for cross-species transferability. The panel was validated across three bi-parental mapping populations totaling 593 progeny. Across these populations, 2,461-3,234 SNP markers were polymorphic and 1,482-2,620 were informative. Each population contained over 900 multiallelic micro-haplotype loci, with several hundred loci exhibiting three or four distinct haplotypes. Markers were uniformly distributed across all 17 chromosomes, each containing between 60- 230 informative SNPs. The panel was further evaluated on 174 diverse germplasm accessions from 20 Malus species. It exhibited strong cross-species transferability, exceptionally low rates of missing data (<0.5%), and clear genetic differentiation between wild and domesticated accessions. Genome-wide association studies (GWAS) identified a major locus on chromosome 4 significantly linked to fruit length, weight, and width in addition to trait-specific associations on chromosomes 1, 6, 9, and 11. The cost-effectiveness of genotyping per sample (<$15), combined with these results, underscore the panels broad utility for quantitative trait locus (QTL) mapping in bi- parental and diverse populations, marker-assisted selection in the breeding programs, and genetic diversity analysis across the Malus genus.

genetics↗

bioRxiv2025

Direct cerebellar control over motor production in a species with extreme cerebellar enlargement

The cerebellum is thought to fine-tune movement without being required for its production. However, this textbook view derives mainly from studies of mammalian species with highly developed cerebral cortices. Here we examined cerebellar function in the elephant-nose fish, a member of a family of African weakly electric fish (Mormyridae) in which the cerebellum is massively enlarged. The elephant-nose fish is named for a flexible facial appendage that is used to probe surfaces and extract prey from substrate. Results from microstimulation, electrophysiological recordings, and lesions support a direct role for the C1 region of the mormyrid cerebellum in controlling movement of this appendage. These findings suggest that the cerebellum is capable of performing functions typically ascribed to the cerebral cortex, emphasizing the importance of evolutionary history on the functional specialization of brain regions.

neuroscience↗

bioRxiv2022

Oncogenic metabolic rewiring independent of proliferative control in human mammary epithelial cells

The use of isotopic tracers and metabolic flux analysis (MFA) has unveiled a number of metabolic pathways differentially activated in cancer cells. To support efforts to design effective metabolic therapies for cancer, we sought to distinguish metabolic behavior in cancer versus normal cells growing at the same rate. To this end, we performed 13C-isotope tracing and MFA in human mammary epithelial cells (HMECs) harboring different combinations of oncogenes. By introducing a new quantity termed metabolic flux intensity, defined as pathway flux divided by specific growth rate, we showed that metabolism is dually controlled by proliferation and oncogenotypes. 13C-MFA further revealed that oxidative pentose phosphate pathway (oxPPP), malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) were most enhanced in cancerous HMECs. Drug targeting of these pathways selectively reduced growth in the tumorigenic HMEC line. Our study provides direct evidence that metabolism of cancer cells is different than that of normal proliferating cells.

biochemistry↗