INVESTIGADORES
SCHNITTGER Leonhard
artículos
Título:
Phylogenetic analysis of Theileria species transmitted by Haemaphysalis qinghaiensis.
Autor/es:
YIN H, LUO J, SCHNITTGER L, LU B, BEYER D, MA M, GUAN G, BAI Q, LU C, AHMED J.
Revista:
PARASITOLOGY RESEARCH
Referencias:
Año: 2004 p. 36 - 42
ISSN:
0932-0113
Resumen:
The phylogenetic relationships between six isolates of Theileria spp.
infective to small ruminants, and two isolates of Theileria spp.
infective to yak, all transmitted by Haemaphysalis qinghaiensis,
together with the Theileria orientalis/sergenti/buffeli group and T.
sinensis, were analyzed using the 18S ssrRNA gene sequence. The target
DNA segment was amplified by polymerase chain reaction (PCR). The PCR
product was used either for direct sequencing or was ligated to the PCR
II vector for sequencing. The length of the 18S ssrRNA gene of all
Theileria spp. involved in this study was around 1,740 bp. Two
phylogenetic trees were inferred based on the 18S ssrRNA gene sequence
of the Chinese isolates only, and Chinese isolates and other species of
Theileria available in GenBank. In the first tree, the Theileria sp.
infective to yaks was found to be T. sinensis. The Theileria sp.
infective to small ruminants was found to be composed of two separate
species of Theileria. Theileria sp. from Qinghai, Madang, Ningxian and
Lintan, which was identical to the unidentified Theileria sp. described
previously, is designated Theileria sp (China 1). The Theileria sp.
from Longde, Zhangjiachuan and Lintan, which has not been described
previously, is designated Theileria sp. (China 2) in order to avoid
confusion. In the second tree, Theileria sp. (China 1) was closely
related to benign Theileria, such as T. buffeli and T. sergenti, while
Theileria sp. (China 2) was separated from other Theileria spp. The
results indicate that H. qinghaiensis transmit at least three species
of Theileria, two which are infective to sheep and goats, but not yak
and one which is infective to yaks and cattle, but not to sheep and
goats.