Professor Zhengfan Jiang from Peking University was invited by the Institute of Biophysics (IBP) to give a report entitled Mn²⁺-cGAS/sGAGs-STING and Mn²⁺-mediated adjuvant and immunotherapy on August 30, 2021. The lecture was presided by Professor Pu Gao. Principal investigators and students from IBP and other institutes attended the report.

Professor Jiang has been committed to the research of infection-immunity-tumor and its cell signal for a long time, focusing on exploring the field of immune surveillance and treatment of virus/tumor by cGAS-STING pathway, and has conducted a series of researches on its physiological function and regulation. Significant progress has been made in related fields, including STING dimerization and activation of transcription factors NFkB and STAT6, which are very important for the immune response to infection; sulfated glycosaminoglycans (sGAGs) are the second type of ligands necessary for STING activation and STING Golgi; STING regulates innate immunity by forming a "phase separator"; Caspases negatively regulates innate immune response, including Caspase activated by inflammasomes and Caspase activated by apoptosis, to avoid excessive immune response and ensure cell apoptosis "immune silence"; 3'3'-cGAMP specific phosphodiesterase was found. In addition, it was found that the PCBPs-AIP4-mediated protein degradation pathway negatively regulates the key molecule of innate immunity, MAVS to reduce or avoid the overreaction caused by RNA virus infection, and NEMO-IKKα/β is essential for activating TBK1/IKKε in the RIG-I-MAVS pathway.

In the report, Professor Jiang introduced his recent research progress on cGAS-STING signaling pathway. Professor Jiang's team conducted a CRISPR-Cas9 genome-wide screening and found that the sulfated glycosaminoglycan synthesized by the Golgi apparatus is the second ligand activated by STING. They also discovered that sulfated glycosaminoglycans directly interact with positive and negative charges to promote the multimerization of STING and activate downstream reactions. They revealed that the high concentration of cGAMP produced in the late stage of virus infection will trigger STING to form a phase separator. In addition, the research team disclosed that manganese ion is the second activator of cGAS in addition to dsDNA.

The report aroused a warm response from the audience, who raised questions of their interest and discussed actively with him.

Prof. Pu Gao hosted the lecture

Prof. Zhengfan Jiang was giving the lecture

Prof. Zhengfan Jiang, Hongyu Deng and Pu Gao

The audience