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Agrobacterium tumefaciens-mediated transformation ( ATMT) is being increasingly recognized as an effective insertional mutagenesis tool in studies of filamentous fungi for gene discovery and functional analysis. We developed and optimized ATMT for 2 Colletotrichum species, Colletotrichum gloeosporioides and Colletotrichum acutatum, the causative agents of Colletotrichum leaf disease in rubber trees in Southern China. A. tumefaciens strain AGL-1 carrying an ILV1 gene and a green fluorescent protein gene were used to transform the conidia of these 2 Colletotrichum species. The transformation efficiency was correlated with the co-cultivation duration and bacterial cell concentrations, which reached 300-400 transformants per 1 × 106 conidia after optimization. Southern blot analysis indicated that about 60.0% of the C. gloeosporioides transformants and 46.2% of the C. acutatum transformants had a single copy of T- DNA in their genomes. Fungal genomic DNA segments flanking the T- DNA were identified in the transformants through thermal asymmetrical interlaced polymerase chain reaction followed by sequencing. The flanking sequences from 4 C. acutatum and 7 C. gloeosporioides transformants showed moderate or weak homology to the NCBI database entries. Some sequences matching those reported virulence-related genes. The results suggest that the T- DNA inserted mutants banks constructed are useful for the discovery of new or important genes and to elucidate their function in the 2 Colletotrichum species. [ABSTRACT FROM AUTHOR]

We studied 1616 bp of mtDNA sequence in plateau pika Ochotona curzoniae sampled from 10 geographical regional groups to study the population history as well as long-term gene flow of O. curzoniae. We detected 153 haplotypes in 245 individuals. Mismatch analyses detected rapid population expansion in nine regional groups. Long-term estimates of gene flow revealed a unidirectional manner from peripheral groups towards central plateau groups. In contrast, gene flow among central plateau groups was bidirectional. Our results indicate that the population expansion of most groups occurred 0.24–0.03 Mya, which mostly coincides with the interglacial period before the last glacial maximum. Gene flow of O. curzoniae was closely related to the different effects of the extensive glacial period (EGP) and the last glacial period (LGP) on the species. The EGP had caused extinction of all central populations, while the LGP had very limited influence on the populations that recolonized the central region. However, the glaciers in the relatively humid areas surrounding the interior of the plateau during the LGP were substantial and had prevented or greatly reduced the ‘counter’ gene flow from the central populations to the edge populations, resulting in a unidirectional gene flow. A hierarchical analysis of molecular variance showed that 55.1% of the total variance was explained by among-groups structuring while 34.2% was explained by the differences among individuals within populations. Compared with other endemic species on the Qinghai-Tibetan Plateau, O. curzoniae has a moderate level of the population genetic structure, which is higher than birds and lower than lizard, due to its limited dispersal ability. [ABSTRACT FROM AUTHOR]

We studied the relationship between genetic diversity of the subterranean Gansu zokor Myospalax cansus and habitat variability in the Loess Plateau, Qinghai Province, China. We used a combination of geographic information systems and molecular techniques to assess the impact of habitat composition and human activities on the genetic diversity of zokor populations in this semi-natural landscape. Although they occurred relatively infrequently in the landscape, woodland and high-coverage grassland habitats were the main positive contributors to the genetic diversity of zokor populations. Rural residential land, plain agricultural land and low-coverage grassland had a negative effect on genetic diversity. Hilly agricultural land and middle-coverage grassland had little impact on zokor genetic diversity. There were also interactions between some habitat types, that is, habitat types with relatively better quality together promoted conservation of genetic diversity, while the interaction between (among) bad habitat types made situations worse. Finally, habitat diversity, measured as patch richness and Shannon's diversity index, was positively correlated with the genetic diversity. These results demonstrated that: (1) different habitat types had different effects on the genetic diversity of zokor populations and (2) habitat quality and habitat heterogeneity were important in maintaining genetic diversity. Habitat composition was closely related to land use thus emphasizing the importance of human activities on the genetic diversity of subterranean rodent populations in this semi-natural landscape. Although the Gansu zokor was considered to be a pest species in the Loess Plateau, our study provides insights for the management and conservation of other subterranean rodent species. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to investigate the clinical value of the bulbocavernosus reflex (BCR) and pudendal nerve somatosensory evoked potentials (PSEPs) in the differential diagnosis between multiple system atrophy (MSA) and Parkinson's disease (PD) in early stage., Materials and Methods: A total of 31 patients with MSA, 45 patients with PD, and 60 healthy participants were included in this study. A Keypoint EMG/EP system was used for BCR and PSEP measurements. Electrophysiological parameters were collected for statistical analysis., Results: The BCR elicitation rates were significantly lower in the patients with MSA than in the patients with PD (P<.05). Prolonged BCR latencies were found in the MSA group compared to the PD and control groups (P<.05). Bulbocavernosus reflex latencies were significantly prolonged in patients with MSA compared with PD patients showing early urogenital symptoms (P<.05). There was no significant difference in PSEP P41 latencies among the three groups (P=.434 in males, P=.948 in females). Both BCR and PSEP amplitudes were significantly lower in the MSA/PD group than in the control group (P<.001)., Conclusions: Pudendal nerve damage is more severe in MSA than in PD. Prolonged BCR latency may be valuable for distinguishing between MSA and PD in the early stages. BCR and PSEP testing may also contribute to localized and qualitative diagnosis of the distribution of neurodegenerative pathologies in these two disorders., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)