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Jing, T.

Publications and source records attributed to Jing, T..

3 recordsLinked to original sources

Oligomeric HIV-1 Integrase Structures Reveal Functional Plasticity for Intasome Assembly and RNA Binding

Integrase (IN) performs dual essential roles during HIV-1 replication. During ingress, IN functions within an oligomeric "intasome" assembly to catalyze viral DNA integration into host chromatin. During late stages of infection, tetrameric IN binds viral RNA and orchestrates the condensation of ribonucleoprotein complexes into the capsid core. The molecular architectures of HIV-1 IN assemblies that mediate these distinct events remain unknown. Furthermore, the tetramer is an important antiviral target for allosteric IN inhibitors. Here, we determined cryo-EM structures of wildtype HIV-1 IN tetramers and intasome hexadecamers. Our structures unveil a remarkable plasticity that leverages IN C-terminal domains and abutting linkers to assemble functionally distinct oligomeric forms. Alteration of a newly recognized conserved interface revealed that both IN functions track with tetramerization in vitro and during HIV-1 infection. Collectively, our findings reveal how IN plasticity orchestrates its diverse molecular functions, suggest a working model for IN-viral RNA binding, and provide atomic blueprints for allosteric IN inhibitor development.

biochemistry↗

Single-cell atlas of human developing and azoospermia patients' testicles reveals the roadmap and defects in somatic microenvironment

Non-obstructive azoospermia (NOA) affects 1% of men. However, the unknowns of NOA pathogenesis and even normal spermatogenic microenvironment establishment severely limit the clinical efficacy of NOA treatment. We profiled > 80,000 human testicular single-cell transcriptomes from 10 healthy donors spanning the range from infant to adult and 7 NOA patients. Sertoli cells, which form the scaffold in the testicular microenvironment, exhibited the most obvious damages in NOA patients. We identified the roadmap of Sertoli cell maturation. Notably, Sertoli cells of patients with congenital causes (Klinefelter syndrome and Y chromosome microdeletions) are mature but with abnormal immune response, while the cells in idiopathic NOA (iNOA) are basically physiologically immature. Furthermore, inhibition of Wnt signaling promotes the maturation of Sertoli cells from iNOA patients, allowing these cells to regain their ability to support germ cell survival. We provide a novel perspective on the development of diagnostic methods and therapeutic targets for NOA.

developmental biology↗

TRIM14 is a key regulator of the type I interferon response during Mycobacterium tuberculosis infection

Tripartite motif-containing proteins (TRIMs) play a variety of recently described roles in innate immunity. While many TRIMs regulate type I interferon (IFN) expression following cytosolic nucleic acid sensing of viruses, their contribution to innate immune signaling and gene expression during bacterial infection remains largely unknown. Because Mycobacterium tuberculosis is a potent activator of cGAS-dependent cytosolic DNA sensing, we set out to investigate a role for TRIM proteins in regulating macrophage responses to M. tuberculosis. Here we demonstrate that TRIM14, a non-canonical TRIM that lacks an E3 ligase RING domain, is a critical negative regulator of the type I IFN response in macrophages. We show that TRIM14 physically interacts with both cGAS and TBK1 and that macrophages lacking TRIM14 dramatically hyperinduce interferon stimulated gene (ISG) expression following cytosolic nucleic acid transfection, IFN-{beta} treatment, and M. tuberculosis infection. Consistent with a defect in resolution of the type I IFN response, Trim14 knockout (KO) macrophages have more phospho-Ser754 STAT3 relative to phospho-727 and fail to upregulate the STAT3 target Socs3 (Suppressor of Cytokine Signaling 3), which is required to turn off IFNAR signaling. These data support a model whereby TRIM14 acts as a scaffold between TBK1 and STAT3 to promote phosphorylation of STAT3 at Ser727 and enhance negative regulation of ISG expression. Remarkably, Trim14 KO macrophages hyperinduce antimicrobials like Inos2 and are significantly better than control cells at limiting M. tuberculosis replication. Collectively, these data reveal a previously unappreciated role for TRIM14 in resolving type I IFN responses and controlling M. tuberculosis infection.

immunology↗