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zeng, l.

Publications and source records attributed to zeng, l..

3 recordsLinked to original sources

A plastidial retrograde-signal potentiates biosynthesis of systemic stress response activators

O_LIPlants employ an array of intricate and hierarchical signaling cascades to perceive and transduce informational cues to synchronize and tailor adaptive responses. Systemic stress response (SSR) is a recognized complex signaling and response network quintessential to plants local and distal responses to environmental triggers, however, the identity of the initiating signals has remained fragmented. C_LIO_LIHere, we show that both biotic (aphids and viral pathogens) and abiotic (high-light and wounding) stresses induce accumulation of the plastidial-retrograde-signaling metabolite, methylerythritol cyclodiphosphate (MEcPP), leading to reduction of the phytohormone, auxin, and the subsequent decreased expression of the phosphatase, PP2C.D1. C_LIO_LIThis enables phosphorylation of mitogen-activated protein kinases (MAPK3/6), and the consequential induction of the downstream events ultimately resulting in biosynthesis of the two SSR priming metabolites, pipecolic- and N-hydroxy-pipecolic acid. C_LIO_LIThis work identifies plastids as the initiation site, and the plastidial retrograde-signal, MEcPP as the initiator of a multi-component signaling cascade potentiating the biosynthesis of SSR activators, in response to biotic and abiotic triggers. C_LI

plant biology↗

CVB3 VP1 interacts with MAT1 to inhibit cell proliferation by interfering with Cdk-activating kinase complex activity in CVB3-induced acute pancreatitis

Coxsackievirus B3 (CVB3) belongs to the genus Enterovirus of the family Picornaviridae and can cause acute acinar pancreatitis in adults. However, the molecular mechanisms of pathogenesis underlying CVB3-induced acute pancreatitis have remained unclear. In this study, we discovered that CVB3 capsid protein VP1 inhibited pancreatic cell proliferation and exerted strong cytopathic effects on HPAC cells. Through yeast two-hybrid, co-immunoprecipitation, and confocal microscopy, we show that Menage a trois 1 (MAT1), a subunit of the Cdk-Activating Kinase (CAK) complex involved in cell proliferation and transcription, is a novel interaction protein with CVB3 VP1. Moreover, CVB3 VP1 inhibited MAT1 accumulation and localization, thus interfering with its interaction with CDK7. Furthermore, CVB3 VP1 could suppress CAK complex enzymic phosphorylation activity towards RNA Pol II and CDK4/6, direct substrates of CAK. VP1 also suppresses phosphorylation of retinoblastoma protein (pRb), an indirect CAK substrate, especially at phospho-pRb Ser780 and phospho-pRb Ser807/811 residues, which are associated with cell proliferation. Finally, we present evidence using deletion mutants that the C-terminal domain (VP1-D8, 768-859aa) is the minimal VP1 region required for its interaction with MAT1, and furthermore, VP1-D8 alone was sufficient to arrest cells in G1/S phase as observed during CVB3 infection. Taken together, we demonstrate that CVB3 VP1 can inhibit CAK complex assembly and activity through direct interaction with MAT1, to block MAT1-mediated CAK-CDK4/6-Rb signaling, and ultimately suppress cell proliferation in pancreatic cells. These findings substantially extend our basic understanding of CVB3-mediated pancreatitis, providing strong candidates for strategic therapeutic targeting.

microbiology↗

Integrated aqueous humor ceRNA and miRNA-TF-mRNA network analysis reveals potential molecular mechanisms governing primary open-angle glaucoma pathogenesis

Primary open-angle glaucoma (POAG) is the leading cause of blindness globally, which develops through complex and poorly understood biological mechanisms. Herein, we conducted an integrated bioinformatics analysis of extant aqueous humor (AH) gene expression datasets in order to identify key genes and regulatory mechanisms governing POAG progression. We downloaded AH gene expression datasets (GSE101727 and GSE105269) corresponding to healthy controls and POAG patients from the Gene Expression Omnibus. We then identified mRNAs, microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) that were differentially expressed (DE) between control and POAG patients. DEmRNAs and DElncRNAs were then subjected to pathway enrichment analyses, after which a protein-protein interaction (PPI) network was generated. This network was then expanded to establish lncRNA-miRNA-mRNA and miRNA-transcription factor(TF)-mRNA networks. In total, the GSE101727 dataset was used to identify 2746 DElncRNAs and 2208 DEmRNAs, while the GSE105269 dataset was used to identify 45 DEmiRNAs. We ultimately constructed a competing endogenous RNA (ceRNA) network incorporating 37, 5, and 14 of these lncRNAs, miRNAs and mRNAs, respectively. The proteins encoded by these 14 hub mRNAs were found to be significantly enriched for activities that may be linked to POAG pathogenesis. In addition, we generated a miRNA-TF-mRNA regulatory network containing 2 miRNAs (miR-135a-5p and miR-139-5p), 5 TFs (TGIF2, TBX5, HNF1A, TCF3, and FOS) and 5 mRNAs (SHISA7, ST6GAC2, TXNIP, FOS, and DCBLD2). The SHISA7, ST6GAC2, TXNIP, FOS, and DCBLD2 genes that may be viable therapeutic targets for the prevention or treatment of POAG, and regulated by the TFs (TGIF2, HNF1A, TCF3, and FOS).

molecular biology↗