Biology subjects

Zhang, C.-M.

Publications and source records attributed to Zhang, C.-M..

4 recordsLinked to original sources

bioRxiv2025

Multiple-level organizational logic of the locus coeruleus-norepinephrine system in structure and function

The locus coeruleus (LC) regulates various neural processes through a limited number of norepinephrine (NE)-releasing neurons with widespread axon projections. However, how the LC is organized to exert brain-wide regulatory functions remain elusive. Utilizing larval zebrafish as a whole-brain-scale model, we reveal that morphologically heterogenous but physiologically comparable LC-NE neurons assemble complementarily to implement region-specific regulation of brain-wide neural dynamics. Individual LC-NE neurons exhibit diverse axon projections with ipsilateral bias and region preference, but share comparable electrophysiological properties, sensory responses and neural function-related genes expression. Moreover, population LC-NE neurons display bilaterally symmetrical yet regionally different axon projections and fire synchronously, causing regionally patterned NE release. Along with the regional comparability of NE receptor expression, these enable the LC to tune brain-wide neural dynamics in an inverted-U manner with region difference. Thus, our study provides a comprehensive understanding of the organizational logic of the LC system.

neuroscience↗

bioRxiv2020

CREB1 contributes colorectal cancer cell plasticity by regulating lncRNA CCAT1 and NF-κB pathways

The CREB1 gene encodes a pleiotropic transcription factor that frequently dysregulated in cancers. CREB1 can regulates tumour cell status of proliferation or migration, however, the molecular basis for this switch involvement in cell plasticity has not been fully understood. Here, we show that knocking out CREB1 triggered a remarkable effect of epithelial-mesenchymal transition (EMT) and led to the occurrence of inhibited proliferation and enhanced motility in cancer cells. Mechanistically, CREB1-knockout cells showed arrest in the G0/G1 phase as a result of impaired CREB1-dependent transcription of CCAT1 and E2F1. Interestingly, the competition between the coactivator CBP/p300 for CREB1 and p65 leads to the activation of the NF-{kappa}B pathway in cells with CREB1 disrupted, which induces an EMT phenotype and enhances motility. These studies identified previously unknown mechanisms of CREB1 in cell plasticity via its lncRNA and protein effector pathways, revealing an important feature that should be considered in CREB1-targeted tumour therapies.

cell biology↗

bioRxiv2019

Chromatin 3D structure reconstruction with consideration of adjacency relationship among genomic loci

Chromatin 3D conformation plays important roles in regulating gene or protein functions. High-throughout chromosome conformation capture (3C)-based technologies, such as Hi-C, have been exploited to acquire the contact frequencies among genomic loci at genome-scale. Various computational tools have been proposed to recover the underlying chromatin 3D structures from in situ Hi-C contact map data. As connected residuals in a polymer, neighboring genomic loci have intrinsic mutual dependencies in building a 3D conformation. However, current methods seldom take this feature into account. We present a method called ShNeigh, which combines the classical MDS technique with local dependence of neighboring loci modelled by a Gaussian formula, to infer the best 3D structure from noisy and incomplete contact frequency matrices. The results obtained on simulations and real Hi-C data showed, while keeping the high-speed nature of classical MDS, ShNeigh is more accurate and robust than existing methods, especially for sparse contact maps. A Matlab implementation of the proposed method is available at https://github.com/fangzhen-li/ShNeigh.\n\nAuthor summaryWe propose a new method to infer a consensus 3D genome structure from a Hi-C contact map. The novelty of our method is that it takes into accounts the adjacency of genomic loci along chromosomes. Specifically, the proposed method penalizes the optimization problem of the classical multidimensional scaling method with a smoothness constraint weighted by a function of the genomic distance between the pairs of genomic loci. We demonstrate this optimization problem can still be solved efficiently by a classical multidimensional scaling method. We then show that the method can recover stable structures in high noise settings. We also show that it can reconstruct similar structures from data obtained using different restriction enzymes.

bioinformatics↗

bioRxiv2017

Discovering the Interactions between Circular RNAs and RNA-binding Proteins from CLIP-seq Data using circScan

Although tens of thousands of circular RNAs (circRNAs) have been identified in mammalian genomes, only few of them have been characterized with biological functions. Here, we report a new approach, circScan, to identify regulatory interactions between circRNAs and RNA-binding proteins (RBPs) by discovering back-splicing reads from Cross-Linking and Immunoprecipitation followed by high-throughput sequencing (CLIP-seq) data. By using our method, we have systematically scanned ~1500 CLIP-seq datasets, and identified ~12540 and ~1090 novel circRNA-RBP interactions in human and mouse genomes, respectively, which include all known interactions between circRNAs and Argonaute (AGO) proteins. More than twenty novel interactions were further experimentally confirmed by RNA Immunoprecipitation quantitative PCR (RIP-qPCR). Importantly, we uncovered that some natural circRNAs interacted with cap-independent translation factors eukaryotic initiation factor 3 (eIF3) and N6-Methyladenosine (m6A), indicating they can be translated into proteins. These findings demonstrate that circRNAs are regulated by various RBPs, suggesting they may play important roles in diverse biological processes.

molecular biology↗