scholarly journals A global phylogenetic analysis in order to determine the host species and geography dependent features present in the evolution of avian H9N2 Influenza Hemagglutinin

Author(s):  
Andrew R Dalby ◽  
Munir Iqbal

A complete phylogenetic analysis of all of the H9N2 hemagglutinin sequences that were collected between 1966 and 2012 was carried out in order to build a picture of the geographical and host specific evolution of the hemagglutinin protein. To improve the quality and applicability of the output data the sequences were divided into subsets based upon location and host species. The phylogenetic analysis of hemagglutinin reveals that the protein has distinct lineages between China and the Middle East, and that wild birds in both regions retain a distinct form of the H9 molecule, from the same lineage as the ancestral hemagglutinin. The results add further evidence to the hypothesis that the current predominant H9N2 hemagglutinin lineage might have originated in Southern China. The study also shows that there are sampling problems that affect the reliability of this and any similar analysis. This raises questions about the surveillance of H9N2 and the need for wider sampling of the virus in the environment. The results of this analysis are also consistent with a model where hemagglutinin has predominantly evolved by neutral drift punctuated by occasional selection events. These selective events have produced the current pattern of distinct lineages in the Middle East, Korea and China. This interpretation is in agreement with existing studies that have shown that there is widespread intra-country sequence evolution.

2014 ◽  
Author(s):  
Andrew R Dalby ◽  
Munir Iqbal

A complete phylogenetic analysis of all of the H9N2 hemagglutinin sequences that were collected between 1966 and 2012 was carried out in order to build a picture of the geographical and host specific evolution of the hemagglutinin protein. To improve the quality and applicability of the output data the sequences were divided into subsets based upon location and host species. The phylogenetic analysis of hemagglutinin reveals that the protein has distinct lineages between China and the Middle East, and that wild birds in both regions retain a distinct form of the H9 molecule, from the same lineage as the ancestral hemagglutinin. The results add further evidence to the hypothesis that the current predominant H9N2 hemagglutinin lineage might have originated in Southern China. The study also shows that there are sampling problems that affect the reliability of this and any similar analysis. This raises questions about the surveillance of H9N2 and the need for wider sampling of the virus in the environment. The results of this analysis are also consistent with a model where hemagglutinin has predominantly evolved by neutral drift punctuated by occasional selection events. These selective events have produced the current pattern of distinct lineages in the Middle East, Korea and China. This interpretation is in agreement with existing studies that have shown that there is widespread intra-country sequence evolution.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 728
Author(s):  
Bao-Gui Jiang ◽  
Ai-Qiong Wu ◽  
Jia-Fu Jiang ◽  
Ting-Ting Yuan ◽  
Qiang Xu ◽  
...  

A novel Borrelia species, Candidatus Borrelia javanense, was found in ectoparasite ticks, Amblyomma javanense, from Manis javanica pangolins seized in anti-smuggling operations in southern China. Overall, 12 tick samples in 227 (overall prevalence 5.3%) were positive for Candidatus B. javanense, 9 (5.1%) in 176 males, and 3 (5.9%) in 51 females. The phylogenetic analysis, based on the 16S rRNA gene and the flagellin gene sequences of the Borrelia sp., exhibited strong evidence that Candidatus B. javanense did not belong to the Lyme disease Borrelia group and the relapsing fever Borrelia group but another lineage of Borrelia. The discovery of the novel Borrelia species suggests that A. javanense may be the transmit vector, and the M. javanica pangolins should be considered a possible origin reservoir in the natural circulation of these new pathogens. To our knowledge, this is the first identification of a novel Borrelia species agent in A. javanense from pangolins. Whether the novel agent is pathogenic to humans is unknown and needs further research.


MycoKeys ◽  
2021 ◽  
Vol 84 ◽  
pp. 103-139
Author(s):  
Guo-Jie Li ◽  
Shou-Mian Li ◽  
Bart Buyck ◽  
Shi-Yi Zhao ◽  
Xue-Jiao Xie ◽  
...  

Three new species of Russulasection Ingratae, found in Guizhou and Jiangsu Provinces, southern China, are proposed: R. straminella, R. subpectinatoides and R. succinea. Photographs, line drawings and detailed morphological descriptions for these species are provided with comparisons against closely-related taxa. Phylogenetic analysis of the internal transcribed spacer (ITS) region supported the recognition of these specimens as new species. Additionally, R. indocatillus is reported for the first time from China and morphological and phylogenetic data are provided for the Chinese specimens.


Author(s):  
Udon Pongkawong ◽  
◽  
Jatupol Kampuansai ◽  
Rossarin Pollawatn ◽  
Arunothai Jampeetong ◽  
...  

Abstract “Dok Hin” is the Thai local name for Selaginella species that form rosettes. They commonly distributes in Siberia, Manchuria, southern China, Japan, the Philippines and Thailand. Morphology of Dok Hin is very resemble leading to misidentification. So, exactly number of species of Dok Hin in Thailand and their differences in morphological characteristics is not well understood. Thus, revision of morphological characters and phylogenetic confirmation of the taxonomic identification are needed. This study aims to examine morphological charateristics and phylogenetic patterns in eight populations of the Dok Hin in Northern Thailand. Morphology of Dok Hin from each populations was quantitatively examined using 15 vegetative and 6 reproductive characters meanwhile phylogenetic analyses was explored by DNA barcode ITS2. The results of the phylogenetic analysis revealed the existence of two species of Dok Hin, S. tamariscina and S. pulvinata. Selaginella tamariscina can be distinguished from S. pulvinata by its presence of a pseudotrunk above ground and ridges of dorsal leaves. On the other hand, the results of phylogenetic analysis indicated the differences among populations of S. pulvinata as well. Chiang Mai populations of S. pulvinata was characterized by peculiar set of characters long leaves and leaf apices look like caudate, while the rest of their populations have shorter leaves and leaf apices look like aristate. It indicates that S. pulvinata has genetic and phenotypic divergence among populations. However, additional studies of Dok Hin populations in other parts of Thailand and studies on different genetic markers are necessary to confirm the taxonomic status of S. pulvinata. Keywords: Dok Hin, Morphometric, Phylogeny, Pseudotrunk, Resurrection plant


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