CHARACTERIZATION OF ATG8 GENE HOMOLOGS IN VERTICILLIUM DAHLIAE AND VERTICILLIUM ALBO-ATRUM

The vascular wilt fungi Verticillium dahliae and the closely related Verticillium albo-atrum are devastating plant pathogens. Both pathogens produce resting structures that accumulate in soil, and are difficult to eradicate. V dahliae produces microsclerotia (MCS), while V albo-atrum produces dark resting mycelia (DRM). The role ofATG8, an autophagy marker was studied by generating A TG8 knockouts in V dahliae (vdatg8), and V albo-atrum (vaatgS). Although dispensable for pathogenicity in both species, in V dahliae ATG8 was involved in dimorphic growth, conidiation, and MCS formation, but not glycogen accumulation. Increased temperatures restored conidiation and MCS formation in vdatg8, indicating that autophagy is involved in, but not essential for MCS formation in V dahliae. In V albo-atrum ATG8 was involved in glycogen accumulation, but not DRM formation. Considerable functional redundancy exists in V dahliae MCS formation, and although VdATG8 and VaATG8 amino acid sequences are almost identical, A TG8 function is species specific

Ten millennia of hepatitis B virus evolution

Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic