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Liguo Zhang

Publications and source records attributed to Liguo Zhang.

3 recordsLinked to original sources

Genome-Wide Characterization of the ScLOR Gene Family in Wild Tomato Solanum lycopersicoides Reveals ScLOR16 as a Negative Regulator of Cold-and Drought-Stress Tolerance.

The LOR (LURP-one related) gene family encodes proteins containing conserved LOR domains; however, its functions in plant abiotic stress responses remain largely unexplored. In this study, we systematically identified and characterized the LOR gene family in the stress-tolerant wild tomato Solanum lycopersicoides using comprehensive bioinformatic analyses and conducted functional validation of the candidate gene ScLOR16. A total of 19 ScLOR members were identified and classified into eight phylogenetic subgroups. Numerous cis-acting elements associated with responses to abscisic acid (ABA), cold, and drought, including ABRE, LTR, and MBS, were detected in the promoter regions, suggesting that the ScLOR family may be broadly involved in ABA-mediated stress signaling pathways. RT-qPCR analysis revealed that ScLOR16 expression was significantly induced by both cold and drought treatments. Subcellular localization assays demonstrated that ScLOR16 is localized in both the nucleus and cytoplasm. Virus-induced gene silencing (VIGS) was subsequently employed to generate ScLOR16-silenced plants. Following 24 h of cold treatment at 4 °C and four days of drought stress, ScLOR16-silenced seedlings exhibited significantly less severe wilting symptoms than empty-vector controls. Physiological analyses showed that silenced plants exhibited enhanced superoxide dismutase (SOD) and peroxidase (POD) activities, increased proline accumulation, and decreased thiobarbituric acid-reactive substances (TBARS) content. Collectively, these results indicate that reduced ScLOR16 transcript levels are associated with enhanced cold and drought tolerance, accompanied by alterations in antioxidant defense and osmoprotection-related physiological markers. This study yields new insights into the evolution and stress-related functions of the ScLOR family.

LOR gene family

Acidic transcription factors position the genome at nuclear speckles through transcription-dependent and -independent mechanisms.

A small fraction of the genome reproducibly positions near nuclear speckles (NSs), increasing the expression and/or splicing efficiency of NS-associated genes. How specific genomic regions in mammalian cells are targeted to NSs remains unclear. Here, we demonstrate the establishment of genome-wide NS association without active transcription. We show that DNA sequences derived from NS-associated regions, when integrated as transgenes, are autonomously targeted to NSs. By systematically dissecting one such genomic locus, the COL1A1-SGCA locus, we identified redundant NS-targeting cis-regulatory elements, including an ∼600-bp fragment with 17 binding motifs for 8 transcription factors (TFs). Four NS-targeting TFs within this fragment contain acidic activation domains (AADs) that provide both chromatin-context and transcription-dependent NS targeting, properties that appear to be common among several other tested AADs. A subset of acidic activator TFs contains an additional, transcription-independent NS-targeting activity. Our findings establish diverse and partially redundant NS-targeting activities, which may facilitate dynamic gene positioning at the NS periphery for context-specific transcriptional responses.

Transcription, Genetic

Genome-Wide Identification of the TIFY Family in Cannabis sativa L. and Its Potential Functional Analysis in Response to Alkaline Stress and in Cannabinoid Metabolism.

TIFY transcription factors play crucial regulatory roles in secondary metabolism and stress response. However, the expression patterns of the Cannabis sativa L. TIFY gene family under alkali stress, their involvement in cannabinoid metabolism, and their underlying genetic evolutionary mechanisms remain largely unexplored. In this study, we used bioinformatics approaches to conduct genome-wide identification and functional characterization of the C. sativa TIFY gene family. Fourteen TIFY genes were identified and mapped onto seven chromosomes. These genes were classified into four subfamilies: TIFY, JAZ, ZML, and PPD, with the JAZ subfamily further subdivided into five distinct branches. Collinearity analysis suggested that gene duplication events contributed to the expansion of the TIFY gene family in C. sativa. Weighted gene coexpression network analysis (WGCNA) revealed that CsJAZ2, CsJAZ3, and CsJAZ6 participated in the cannabinoid regulatory network. Cis-element analysis indicated that the promoter regions of TIFY genes were enriched in hormone- and stress-responsive elements. Furthermore, transcriptome and RT-qPCR analyses were conducted to examine gene expression patterns under alkaline stress (the RNA employed in RT-qPCR was extracted from the apical leaves of samples subjected to short-duration alkaline stress treatment). The results showed that CsJAZ5 and CsJAZ6 were downregulated, whereas CsPPD1, CsTIFY1, and CsZML1 were upregulated in response to alkali stress. In summary, CsJAZ5, CsPPD1, and CsTIFY1 may serve as candidate genes for the development of alkali-tolerant cultivars, while CsJAZ2 and CsJAZ3 may be valuable targets for enhancing cannabinoid production. This study provides important molecular insights and a theoretical basis for future research on the evolutionary dynamics and functional roles of TIFY transcription factors, particularly in stress adaptation and cannabinoid metabolism.

Cannabis