Phylogeographic Patterns of Microtus fortis (Arvicolinae: Rodentia) in China Based on Mitochondrial DNA Sequences

Reanalysis on Phylogeographic Pattern of Sharpbelly Hemiculter leucisculus (Cyprinidae: Cultrinae) in China: A Review and the Implications for Conservation

Hemiculter leucisclus, as a widely distributed freshwater fish in China, provides an interesting model to explore the impact of drainage evolution and geologic history in the Pleistocene on diversification patterns. We collected the mitochondrial cytochrome b (cytb) gene and the recombination activating gene 2 (RAG2) from 1,070 individuals from 59 sampling locations. Phylogenetic and population genetic approaches were used to describe the phylogeographic pattern and to test how the geological and climatic factors on diversification. The results suggested that there existed four sublineages of the H. leucisclus across six river systems, among which two sublineages, showing strongly indigenous characteristics, are constrained to particular geographical regions in China. The molecular data and ancestral states demonstrated that the H. leucisclus possibly originated from the Pearl River basin during the later Pliocene. The phylogeographic pattern in H. leucisclus appears to have been driven by palaeoenvironmental perturbations rather than anthropogenic translocations. The geographically constrained sublineages A in the middle and lower Pearl River basin and sublineage B in the upper Yangtze River basin deserves special protection.

Phylogeny and evolution of Lasiopodomys in subfamily Arvivolinae based on mitochondrial genomics

The species of Lasiopodomys Lataste 1887 with their related genera remains undetermined owing to inconsistent morphological characteristics and molecular phylogeny. To investigate the phylogenetic relationship and speciation among species of the genus Lasiopodomys, we sequenced and annotated the whole mitochondrial genomes of three individual species, namely Lasiopodomys brandtii Radde 1861, L. mandarinus Milne-Edwards 1871, and Neodon (Lasiopodomys) fuscus Büchner 1889. The nucleotide sequences of the circular mitogenomes were identical for each individual species of L. brandtii, L. mandarinus, and N. fuscus. Each species contained 13 protein-coding genes (PCGs), 22 transfer RNAs, and 2 ribosomal RNAs, with mitochondrial genome lengths of 16,557 bp, 16,562 bp, and 16,324 bp, respectively. The mitogenomes and PCGs showed positive AT skew and negative GC skew. Mitogenomic phylogenetic analyses suggested that L. brandtii, L. mandarinus, and L. gregalis Pallas 1779 belong to the genus Lasiopodomys, whereas N. fuscus belongs to the genus Neodon grouped with N. irene. Lasiopodomys showed the closest relationship with Microtus fortis Büchner 1889 and M. kikuchii Kuroda 1920, which are considered as the paraphyletic species of genera Microtus. T_MRCA and niche model analysis revealed that Lasiopodomys may have first appeared during the early Pleistocene epoch. Further, L. gregalis separated from others over 1.53 million years ago (Ma) and then diverged into L. brandtii and L. mandarinus 0.76 Ma. The relative contribution of climatic fluctuations to speciation and selection in this group requires further research.

Changes of intestinal microflora diversity in diarrhea model of KM mice and effects of Psidium guajava L. as the treatment agent for diarrhea

OBJECTIVES

This study aimed to explore the effects of Psidium guajava L. extracts on mice diarrhea model and changes in their intestinal microflora diversity.

METHODS

Mice diarrhea model was constructed with Folium Sennae. and The therapeutic effects of Psidium guajava L. extracts on diarrhea were evaluated by loose stools rates, diarrhea rates, diarrhea index and motor functions of intestine.

RESULTS

Our results showed that all three kinds of extracts from Psidium guajava L. had inhibitory effects on Folium Sennae -induced diarrhea model. The proportion of Bacteroidetes is lower in Group DF (diarrhea model group) compared with Group B (blank group), while abundance of Deferribacteraceae was found in Group DF. The proportion of Deferribacteraceae lowered in Group DTF (diarrhea treatment group) treated with extracts from Psidium guajava L.

CONCLUSIONS

However, mechanisms underlying the therapeutic effect of Psidium guajava L. and the changes in intestinal microflora still await further exploration.