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Xiaoling Liu

Publications and source records attributed to Xiaoling Liu.

3 recordsLinked to original sources

Repeat region engineering of Cas13a crRNA enables conformational gating-based autocatalytic CRISPR biosensing.

CrRNA engineering has emerged as a pivotal strategy for extending CRISPR-Cas13a biosensing. However, structural modulation of the direct repeat (DR) region remains exceptionally challenging due to its intricate architecture and the high energetic barrier of the Cas13a-crRNA interface, which is conventionally viewed as a rigid and immutable scaffold. Here, we demonstrate that the DR region is instead a programmable topological element with unexpected structural plasticity. By systematically engineering the DR through sequence insertion and structural splitting, we identified multiple DR variants that retain robust catalytic activity. Crucially, this topological reconfiguration enables Cas13a activity to be precisely gated by unmodified nucleic acid blockers, a level of regulation unattainable with the wild-type crRNA. Building on this flexible modulation, we developed Dre-CRISPR, a DR-engineered platform that couples target-triggered DR restoration to a self-reinforcing autocatalytic loop. This self-amplifying system provides a 2 × 106-fold sensitivity enhancement over nonamplified systems. Furthermore, the Dre-CRISPR platform extends the diagnostic scope of Cas13a to a broader spectrum of analytes, ranging from microRNAs to enzymatic activities and heavy metal ions. Our findings redefine the crRNA scaffold as a versatile signaling node and provide a generalizable framework for developing high-sensitivity, self-amplifying CRISPR biosensors through topology-driven guide RNA engineering.

CRISPR-Associated Proteins

Integrated single-cell RNA sequencing and mendelian randomization analysis identifies causal immune-related driver genes in the heart failure inflammatory microenvironment.

BACKGROUND: Heart failure (HF) is a major global cause of cardiovascular death and disability. Chronic inflammation and immune dysregulation are critical in its development. The cardiac immune microenvironment, especially macrophages, drives HF progression, yet its molecular mechanisms and prognostic impact are not fully clear. This study aimed to identify causal immune-related driver genes in the HF inflammatory microenvironment. METHODS: We combined single-cell RNA sequencing (scRNA-seq) and Mendelian randomization (MR) to study how the inflammatory immune microenvironment affects HF risk. Using two public scRNA-seq datasets, we identified differentially expressed genes (DEGs) in HF heart tissues and selected 489 candidate genes. Causal relationships between these genes and HF were tested using expression quantitative trait loci (eQTL) data and HF genome-wide association study (GWAS) summary statistics. RESULTS: MR analysis showed that 65 genes were causally linked to HF risk. These genes were enriched in pathways related to cardiomyopathy, leukocyte migration, natural killer (NK) cell cytotoxicity, neutrophil extracellular traps, and NF-κB signaling. HF hearts displayed increased levels of macrophages, T cells, B cells, lymphoid cells, and mast cells, while neutrophils were reduced. CONCLUSIONS: Our integrated analysis reveals the central role of the cardiac inflammatory immune microenvironment in HF and identifies 65 key genes causally associated with HF susceptibility. These genes influence specific immune pathways and cell infiltration, shaping HF progression, and provide a basis for developing new biomarkers and immune-targeted therapies.

Heart failure (HF)

OLFML2B promotes hepatocellular carcinoma malignancy via the PI3K/AKT-EMT axis and correlates with an immunosuppressive tumor microenvironment.

INTRODUCTION: Hepatocellular carcinoma (HCC) is a leading cause of global cancer-related mortality, highlighting the need for novel biomarkers and therapeutic targets. METHODS: The role of Olfactomedin-like 2B (OLFML2B) in HCC was investigated through multi-database analyses (The Cancer Genome Atlas, International Cancer Genome Consortium, Gene Expression Omnibus) and experimental validation. RESULTS: OLFML2B was significantly upregulated in HCC tissues, correlated with poor overall and disease-specific survival, clinicopathological features (tumor grade, stage, age, gender), and robust diagnostic performance (AUC > 0.7 across 14/15 datasets). Transcriptomic and single-cell analyses further revealed that high OLFML2B expression was associated with an immunosuppressive tumor microenvironment, characterized by increased infiltration of M2 macrophages, cancer-associated fibroblasts (CAFs), and regulatory T cells (Tregs), as well as reduced abundance of cytotoxic T cells and NK cells. Knockdown of OLFML2B suppressed malignant phenotypes, including cell proliferation, migration, invasion, and angiogenesis, attenuated PI3K/AKT-EMT signaling, and enhanced sensitivity to sorafenib, cabozantinib, and regorafenib in Huh7 and HepG2 cells. Additionally, OLFML2B knockdown suppressed tumor growth and metastasis in zebrafish xenografts. DISCUSSION: Collectively, these findings indicate that OLFML2B is required for HCC progression and represents a prognostic biomarker and potential therapeutic target.

Humans