[Mechanism of Platycarya strobilacea Sieb. et Zucc extract-induced methuosis in human nasopharyngeal carcinoma CNE1 and CNE2 cells]

OBJECTIVE

To study the effect of Platycarya strobilacea Sieb. et Zucc (PSZ) extract on methuosis of human nasopharyngeal carcinoma CNE1 and CNE2 cells and explore the underlying mechanism.

METHODS

CNE1 and CNE2 cells were treated with 1 mg/mL PSZ extract and the expressions of Rac1 mRNA and Rac1 protein were detected using RT-qPCR and Western blotting, respectively. Results CNE1 and CNE2 cells showed obvious morphological changes typical of methuosis following treatment with PSZ extract characterized by cell merging, accumulation of large cytoplasmic vacuoles, and membrane rupture without obvious changes in the nuclei. PSZ treatment resulted in up-regulated Rac1 mRNA and Rac1 protein expressions in the cells. Application of EHT 1864 obviously blocked the effect of PSZ extract in inducing methuosis in CNE1 and CNE2 cells.

CONCLUSION

PSZ extract can induce methuosis in CNE1 and CNE2 cells by inducing the overexpression of Rac1.

[Phenotypic diversity of natural Cyclocarya paliurus populations seed traits]

With the seeds from nine natural Cyclocarya paliurus populations as test materials, their phenotypic traits, including 1000-seed weight, seed size, seed diameter, seed thickness, and seed diameter/thickness ratio, were investigated, and the phenotypic diversity among and within the populations were studied by the methods of ANOVA analysis, hierarchical cluster analysis, and correlation analysis. Significant differences were observed in the 1000-seed weight, seed size, seed diameter, and seed thickness among and within the populations, and in the seed diameter/thickness ratio within the populations, illustrating that there existed high phenotypic diversity of seed traits at these two levels. The mean phenotypic differentiation coefficient (V) of test seed traits was 20.54%, i. e., the variation among the populations was far smaller than that (79.46%) within the populations. The seed traits had different correlation degrees with geographical factors, and most affected by mean annual air temperature. According to the hierarchical cluster analysis based on the Euclidean distance, the nine natural Cyclocarya paliurus populations could be classified into three groups.

Phylogeny of Extant and Fossil Juglandaceae Inferred from the Integration of Molecular and Morphological Data Sets

It is widely acknowledged that integrating fossils into data sets of extant taxa is imperative for proper placement of fossils, resolution of relationships, and a better understanding of character evolution. The importance of this process has been further magnified because of the crucial role of fossils in dating divergence times. Outstanding issues remain, including appropriate methods to place fossils in phylogenetic trees, the importance of molecules versus morphology in these analyses, as well as the impact of potentially large amounts of missing data for fossil taxa. In this study we used the angiosperm clade Juglandaceae as a model for investigating methods of integrating fossils into a phylogenetic framework of extant taxa. The clade has a rich fossil record relative to low extant diversity, as well as a robust molecular phylogeny and morphological database for extant taxa. After combining fossil organ genera into composite and terminal taxa, our objectives were to (1) compare multiple methods for the integration of the fossils and extant taxa (including total evidence, molecular scaffolds, and molecular matrix representation with parsimony [MRP]); (2) explore the impact of missing data (incomplete taxa and characters) and the evidence for placing fossils on the topology; (3) simulate the phylogenetic effect of missing data by creating "artificial fossils"; and (4) place fossils and compare the impact of single and multiple fossil constraints in estimating the age of clades. Despite large and variable amounts of missing data, each of the methods provided reasonable placement of both fossils and simulated "artificial fossils" in the phylogeny previously inferred only from extant taxa. Our results clearly show that the amount of missing data in any given taxon is not by itself an operational guideline for excluding fossils from analysis. Three fossil taxa (Cruciptera simsonii, Paleoplatycarya wingii, and Platycarya americana) were placed within crown clades containing living taxa for which relationships previously had been suggested based on morphology, whereas Polyptera manningii, a mosaic taxon with equivocal affinities, was placed firmly as sister to two modern crown clades. The position of Paleooreomunnea stoneana was ambiguous with total evidence but conclusive with DNA scaffolds and MRP. There was less disturbance of relationships among extant taxa using a total evidence approach, and the DNA scaffold approach did not provide improved resolution or internal support for clades compared to total evidence, whereas weighted MRP retained comparable levels of support but lost crown clade resolution. Multiple internal minimum age constraints generally provided reasonable age estimates, but the use of single constraints provided by extinct genera tended to underestimate clade ages.