C-C motif chemokine ligand 2 (CCL2) is a member of the monocyte chemokine protein family, which binds to its receptor CCR2 to induce monocyte infiltration and mediate inflammation. The CCL2/CCR2 signaling pathway participates in the transduction of neuroinflammatory information between all types of cells in the central nervous system. Animal studies and clinical trials have shown that CCL2/CCR2 mediate the pathological process of ischemic stroke, and a higher CCL2 level in serum is associated with a higher risk of any form of stroke. In the acute phase of cerebral ischemia-reperfusion, the expression of CCL2/CCR2 is increased in the ischemic penumbra, which promotes neuroinflammation and enhances brain injury. In the later phase, it participates in the migration of neuroblasts to the ischemic area and promotes the recovery of neurological function. CCL2/CCR2 gene knockout or activity inhibition can reduce the nerve inflammation and brain injury induced by cerebral ischemia-reperfusion, suggesting that the development of drugs regulating the activity of the CCL2/CCR2 signaling pathway could be used to prevent and treat the cell injury in the acute phase and promote the recovery of neurological function in the chronic phase in ischemic stroke patients.

Ulleung Island is a biodiversity hot spot harboring approximately 700 species of vascular plants with high number of endemic taxa. Physocarpus insularis, one of the 41 endemic species, has an extremely restricted distribution range on the very small, geologically young oceanic island. Phylogenetic relationship of P. insularis, however, remained highly controversial whether it is conspecific with Spiraea chamaedryfolia or a distinct species in Physocarpus, making it difficult to establish necessary conservation programs. We examined comparative morphology of Physocarpus and Spiraea and reconstructed the phylogeny of the rbcL, matK, ndhF, and trnL-trnF regions from the exemplars of Rosaceae. The results strongly supported the placement of P. insularis within Spiraea. Further phylogenetic analyses of tribe Spiraeeae based on the trnL-trnF and internal transcribed spacer data showed that P. insularis is closely related to S. chamaedryfolia. Morphological analysis revealed that P. insularis differs from S. chamaedryfolia by having larger leaf blades that are subcordate or truncate at base. Results of this study suggest that P. insularis should be recognized as a distinct taxon in Spiraea and that conservation efforts on Ulleung Island should focus on protecting its natural environment to conserve evolutionary patterns and processes in addition to specific conservation programs for species in peril.

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Pyruvate kinase (PK) is one of the three rate-limiting enzymes of glycolysis, and it plays a pivotal role in energy metabolism. In this study, we have identified 10 PK genes from the rice genome. Initially, these genes were divided into two categories: cytoplasmic pyruvate kinase (PKc) and plastid pyruvate kinase (PKp). Then, an expression analysis revealed that OsPK1, OsPK3, OsPK4, OsPK6, and OsPK9 were highly expressed in grains. Moreover, PKs can form heteropolymers. In addition, it was found that ABA significantly regulates the expression of PK genes (OsPK1, OsPK4, OsPK9, and OsPK10) in rice. Intriguingly, all the genes were found to be substantially involved in the regulation of rice grain quality and yield. For example, the disruption of OsPK3, OsPK5, OsPK7, OsPK8, and OsPK10 and OsPK4, OsPK5, OsPK6, and OsPK10 decreased the 1000-grain weight and the seed setting rate, respectively. Further, the disruption of OsPK4, OsPK6, OsPK8, and OsPK10 through the CRISPR/Cas9 system showed an increase in the content of total starch and a decrease in protein content compared to the WT. Similarly, manipulations of the OsPK4, OsPK8, and OsPK10 genes increased the amylose content. Meanwhile, the grains of all CRISPR mutants and RNAi lines, except ospk6, showed a significant increase in the chalkiness rate compared to the wild type. Overall, this study characterizes the functions of all the genes of the PK gene family and shows their untapped potential to improve rice yield and quality traits.