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Jing Zhang

Publications and source records attributed to Jing Zhang.

4 recordsLinked to original sources

The Amyloid Structure of Mouse RIPK3 (Receptor Interacting Protein Kinase 3) in Cell Necroptosis

RIPK3 amyloid complex plays crucial roles in execution of TNF-induced necroptosis and in response to immune defense in both human and mouse. We have structurally characterized the mouse RIPK3 homogeneous self-assembly using solid-state NMR, illustrating a well-ordered N-shaped amyloid core structure featured with 3 parallel in-register {beta}-sheets. The structure is different from previously published human RIPK1/RIPK3 hetero-amyloid complex. Functional studies indicate both RIPK1-RIPK3 binding and RIPK3 amyloid formation are essential but not sufficient for RIPK3-mediated necroptosis. The structural integrity of RIPK3 fibril with three {beta}-strands is necessary for the signaling. Molecular dynamics simulation of the mouse RIPK1/RIPK3 model indicates less stable for the hetero-amyloid to adopt RIPK3 fibril conformation, suggesting a structural transformation of RIPK3 from RIPK1-RIPK3 binding to RIPK3 amyloid formation. This structural transformation is revealed for the first time, providing a missing link connecting RIPK1-RIPK3 binding to RIPK3 homo-oligomer formation in the signal transduction.

biochemistry↗

Kindlin2-mediated phase separation underlies integrin adhesion formation

Formation of cell-extracellular matrix adhesion requires assembly of the transmembrane receptor integrins and their intracellular activators, kindlin and talin proteins in minutes. The mechanisms governing the rapid formation and dynamics of the adhesion remain enigmatic. Here, we reported that the dimerized-kindlin2 underwent phase separation with clustered-integrin in solution and on lipid bilayer. The kindlin2/integrin condensate can further enrich other components for the adhesion complex assembly. The full-length structure of kindlin2 was solved and revealed that the kindlin2 dimers can further pack with each other to form a higher oligomer. Disrupting the intermolecular interaction between the kindlin2 dimer inhibits the phase formation on 2D membrane in vitro and impaired the adhesion formation, integrin activation, and cell spreading in cultured cells. We also determined the full-length structure of kindlin2 in its monomeric conformation. Structural analysis and biochemical characterization indicate that the interdomain interaction control the monomer-dimer transition of kindlin2, providing a regulation mechanism of the kindlin2-mediated phase separation. Our findings not only provide a mechanistic explanation for the formation and dynamic regulation of the integrin-based adhesion, but also shed light on understanding of how the clustered receptors participate in assembly of the functional membrane domains via phase separation.

biochemistry↗

Genome-wide characterization of PRE-1 reveals a hidden evolutionary relationship between suidae and primates

We identified and characterized a free PRE-1 element inserted into the promoter region of the porcine IGFBP7 gene whose integration mechanisms into the genome, including copy number, distribution preferences, capacity to exonize and phyloclustering pattern are similar to that of the primate Alu element. 98% of these PRE-1 elements also contain two conserved internal AluI restriction enzyme recognition sites, and the RNA structure of PRE1 can be folded into a two arms model like the Alu RNA structure. It is more surprising that the length of the PRE-1 fragments is nearly the same in 20 chromosomes and positively correlated to its fracture site frequency. All of these fracture sites are close to the mutation hot spots of PRE-1 families, and most of these hot spots are located in the non-complementary fragile regions of the PRE-1 RNA structure. Sequence homology analysis showed that the PRE-1 element seemed to share a common ancestor 7SL RNA with primates but was generated by different evolutionary model, which suggests that the suidae may be the closest relatives to primates in laurasiatheria.

Genomics↗

Genome of octoploid plant maca (Lepidium meyenii) illuminates genomic basis for high altitude adaptation in the central Andes

Maca (Lepidium meyenii Walp, 2n = 8x = 64) of Brassicaceae family is an Andean economic plant cultivated on the 4000-4500 meters central sierra in Peru. Considering the rapid uplift of central Andes occurred 5 to 10 million years ago (Mya), an evolutionary question arises on how plants like maca acquire high altitude adaptation within short geological period. Here, we report the high-quality genome assembly of maca, in which two close-spaced maca-specific whole genome duplications (WGDs, [~] 6.7 Mya) were identified. Comparative genomics between maca and close-related Brassicaceae species revealed expansions of maca genes and gene families involved in abiotic stress response, hormone signaling pathway and secondary metabolite biosynthesis via WGDs. Retention and subsequent evolution of many duplicated genes may account for the morphological and physiological changes (i.e. small leaf shape and loss of vernalization) in maca for high altitude environment. Additionally, some duplicated maca genes under positive selection were identified with functions in morphological adaptation (i.e. MYB59) and development (i.e. GDPD5 and HDA9). Collectively, the octoploid maca genome sheds light on the important roles of WGDs in plant high altitude adaptation in the Andes.

Genomics↗