No abstract

Extracellular vesicles (EVs) hold great promise for transporting CRISPR–Cas9 RNA-guided endonucleases (RNP) throughout the body. However, the cell-selective delivery of EVs is still a challenge. Here, we designed valency-controlled tetrahedral DNA nanostructures (TDNs) conjugated with DNA aptamer, and loaded the valency-controlled TDNs on EV surface via cholesterol anchoring for specific cell targeting. The targeting efficacy of different ratios of aptamer/cholesterol from 1:3 to 3:1 in TDNs on decorating EVs was investigated. TDNs with one aptamer and three cholesterol anchors (TDN1) efficiently facilitated the tumor-specific accumulation of the EVs in cultured HepG2 cells and human primary liver cancer-derived organoids, as well as xenograft tumor models. The intracellular delivery of RNP by TDN1-EVs successfully realized its subsequent genome editing, leading to the downregulation of GFP or WNT10B in specific cells. This system was ultimately applied to reduce the protein expression of WNT10B, which presented remarkable tumor growth inhibition in vitro, ex vivo and in vivo, and could be extended to other therapeutic targets. The present study provides a platform for the directional display of aptamer on surface labeling and the EVs-based Cas9 delivery, which provides a meaningful idea for future cell-selective gene editing.

Tumor cell migration is a well-orchestrated multistep process that drives cancer development and metastasis. Previous data indicated that CD146 expression correlates with malignant progression and metastatic potential of human melanoma cells. However, the exact molecular mechanism of how CD146 promotes melanoma cell migration still remains poorly understood. Here, we report that CD146 physically interacts with actin-linking ezrin-radixin-moesin (ERM) proteins and recruits ERM proteins to cell protrusions, promoting the formation and elongation of microvilli. Moreover, CD146-promoted melanoma cell migration is linked to RhoA activation and ERM phosphorylation. CD146 recruits Rho guanine nucleotide dissociation inhibitory factors 1 (RhoGDI1) through ERM proteins and thus sequesters RhoGDI1 from RhoA, which leads to upregulated RhoA activity and increased melanoma cell motility. CD146-activated RhoA also promotes further ERM phosphorylation and activation through Rho-phosphatidylinositol-4-phosphate-5-kinase-phosphatidylinositol 4,5-biphosphate pathway, which reinforces CD146/ERM association. Thus, our results provide a mechanistic basis to understand the role of CD146 in regulating human melanoma cell motility.

Cinnamomum camphora, a member of the Lauraceae family, is a valuable aromatic and timber tree that is indigenous to the south of China and Japan. All parts of Cinnamomum camphora have secretory cells containing different volatile chemical compounds that are utilized as herbal medicines and essential oils. Here, we reported the complete sequencing of the chloroplast genome of Cinnamomum camphora using illumina technology. The chloroplast genome of Cinnamomum camphora is 152,570 bp in length and characterized by a relatively conserved quadripartite structure containing a large single copy region of 93,705 bp, a small single copy region of 19,093 bp and two inverted repeat (IR) regions of 19,886 bp. Overall, the genome contained 123 coding regions, of which 15 were repeated in the IR regions. An analysis of chloroplast sequence divergence revealed that the small single copy region was highly variable among the different genera in the Lauraceae family. A total of 40 repeat structures and 83 simple sequence repeats were detected in both the coding and non-coding regions. A phylogenetic analysis indicated that Calycanthus is most closely related to Lauraceae, both being members of Laurales, which forms a sister group to Magnoliids. The complete sequence of the chloroplast of Cinnamomum camphora will aid in in-depth taxonomical studies of the Lauraceae family in the future. The genetic sequence information will also have valuable applications for chloroplast genetic engineering.