Accumulation of L-type bovine prions in peripheral nerve tissues.

We recently reported the intraspecies transmission of L-type atypical bovine spongiform encephalopathy (BSE). To clarify the peripheral pathogenesis of L-type BSE, we studied prion distribution in nerve and lymphoid tissues obtained from experimentally challenged cattle. As with classical BSE prions, L-type BSE prions accumulated in central and peripheral nerve tissues.

Intraspecies transmission of L-type-like Bovine Spongiform Encephalopathy detected in Japan.

It has been assumed that the agent causing BSE in cattle is a uniform strain (classical BSE); however, different neuropathological and molecular phenotypes of BSE (atypical BSE) have been recently reported. We demonstrated the successful transmission of L-type-like atypical BSE detected in Japan (BSE/JP24 isolate) to cattle. Based on the incubation period, neuropathological hallmarks, and molecular properties of the abnormal host prion protein, the characteristics of BSE/JP24 prion were apparently distinguishable from the classical BSE prion and closely resemble those of bovine amyloidotic spongiform encephalopathy prion detected in Italy.

Phylogeography of wild musk shrew (Suncus murinus) populations in Asia based on blood protein/enzyme variation.

The musk shrew (Suncus murinus) is an insectivore species that inhabits tropical and subtropical Asia widely. To clarify the genetic relationship among wild musk shrew populations, we examined the electrophoretic variants of biparentally inherited genetic markers at 10 loci coding for eight blood proteins/enzymes in a total of 639 animals and compared the results obtained from the mitochondrial DNA data. The principal-component analysis performed using the allele frequency data revealed that the 17 populations could be divided into two major groups, a South Asian group and a Southeast Asian group that includes several island populations bound by Myanmar.

Population structure of wild musk shrews (Suncus murinus) in Asia based on mitochondrial DNA variation, with research in Cambodia and Bhutan.

The musk shrew (Suncus murinus) is a small mammalian species belonging to Insectivora. It is widely distributed in Asia. To identify the genetic relationship among wild musk shrew populations and examine its migration route, we investigated the populations of Cambodia and Bhutan by using mitochondrial DNA restriction fragment length polymorphism analysis and compared them with other Asian populations previously described.