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1. The early Aurignacian dispersal of modern humans into westernmost Eurasia

   https://doi.org/10.1073/pnas.2016062117  

   Haws, Jonathan A. ; Benedetti, Michael M. ; Talamo, Sahra ; Bicho, Nuno ; Cascalheira, João ; Ellis, M. Grace ; Carvalho, Milena M. ; Friedl, Lukas ; Pereira, Telmo ; Zinsious, Brandon K. ( October 2020 , Proceedings of the National Academy of Sciences)

   Documenting the first appearance of modern humans in a given region is key to understanding the dispersal process and the replacement or assimilation of indigenous human populations such as the Neanderthals. The Iberian Peninsula was the last refuge of Neanderthal populations as modern humans advanced across Eurasia. Here we present evidence of an early Aurignacian occupation at Lapa do Picareiro in central Portugal. Diagnostic artifacts were found in a sealed stratigraphic layer dated 41.1 to 38.1 ka cal BP, documenting a modern human presence on the western margin of Iberia ∼5,000 years earlier than previously known. The data indicate amore »rapid modern human dispersal across southern Europe, reaching the westernmost edge where Neanderthals were thought to persist. The results support the notion of a mosaic process of modern human dispersal and replacement of indigenous Neanderthal populations.« less
2. Reintroduction of the archaic variant of NOVA1 in cortical organoids alters neurodevelopment

   https://doi.org/10.1126/science.aax2537  

   Trujillo, Cleber A. ; Rice, Edward S. ; Schaefer, Nathan K. ; Chaim, Isaac A. ; Wheeler, Emily C. ; Madrigal, Assael A. ; Buchanan, Justin ; Preissl, Sebastian ; Wang, Allen ; Negraes, Priscilla D. ; et al ( February 2021 , Science)

   The evolutionarily conserved splicing regulator neuro-oncological ventral antigen 1 (NOVA1) plays a key role in neural development and function.NOVA1also includes a protein-coding difference between the modern human genome and Neanderthal and Denisovan genomes. To investigate the functional importance of an amino acid change in humans, we reintroduced the archaic allele into human induced pluripotent cells using genome editing and then followed their neural development through cortical organoids. This modification promoted slower development and higher surface complexity in cortical organoids with the archaic version ofNOVA1. Moreover, levels of synaptic markers and synaptic protein coassociations correlated with altered electrophysiological properties in organoidsmore »expressing the archaic variant. Our results suggest that the human-specific substitution inNOVA1, which is exclusive to modern humans since divergence from Neanderthals, may have had functional consequences for our species’ evolution.

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3. Modeling Agrilus planipennis F. (Coleoptera: Buprestidae) Spread in New Jersey

   https://doi.org/10.1093/jee/toz122  

   Lyttek, Erik ; Lal, Pankaj ; Nieddu, Garrett ; Forgoston, Eric ; Wieczerak, Taylor ; Schowalter, ed., Timothy ( May 2019 , Journal of Economic Entomology)

   Pests and disease have become an increasingly common issue as globalized trade brings non-native species into unfamiliar systems. Emerald ash borer (Agrilus planipennis), is an Asiatic species of boring beetle currently devastating the native population of ash (Fraxinus) trees in the northern forests of the United States, with 85 million trees having already succumbed across much of the Midwest. We have developed a reaction-diffusion partial differential equation model to predict the spread of emerald ash borer over a heterogeneous 2-D landscape, with the initial ash tree distribution given by data from the Forest Inventory and Analysis. As expected, themore »model predictions show that emerald ash borer consumes ash which causes the local ash population to decline, while emerald ash borer spreads outward to other areas. Once the local ash population begins to decline emerald ash borer also declines due to the loss of available habitat. Our model’s strength lies with its focus on the county scale and its linkage between emerald ash borer population growth and ash density. This enables one to make accurate predictions regarding emerald ash borer spread which allows one to consider various methods of control as well as to accurately study the economic effects of emerald ash borer spread.

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4. Activation of the autophagy pathway decreases dengue virus infection in Aedes aegypti cells

   https://doi.org/10.1186/s13071-021-05066-w  

   Chen, Tse-Yu ; Smartt, Chelsea T. ( October 2021 , Parasites & Vectors)

   Mosquito-borne dengue virus (DENV) causes major disease worldwide, impacting 50–100 million people every year, and is spread by the major mosquito vectorAedes aegypti. Understanding mosquito physiology, including antiviral mechanisms, and developing new control strategies have become an important step towards the elimination of DENV disease. In the study reported here, we focused on autophagy, a pathway suggested as having a positive influence on virus replication in humans, as a potential antiviral target in the mosquito.

   To understand the role played by autophagy inAe. aegypti, we examined the activation of this pathway in Aag-2 cells, anAe. aegypti-derived cell line, infectedmore »with DENV. Rapamycin and 3-methyladenine, two small molecules that have been shown to affect the function of the autophagy pathway, were used to activate or suppress, respectively, the autophagy pathway.

   At 1-day post-DENV infection in Aag-2 cells, transcript levels of both the microtubule-associated protein light chain 3-phosphatidylethanolamine conjugate (LC3-II) and autophagy-related protein 1 (ATG1) increased. Rapamycin treatment activated the autophagy pathway as early as 1-h post-treatment, and the virus titer had decreased in the Aag-2 cells at 2 days post-infection; in contrast, the 3-methyladenine treatment did not significantly affect the DENV titer. Treatment with these small molecules also impacted the ATG12 transcript levels in DENV-infected cells.

   Our studies revealed that activation of the autophagy pathway through rapamycin treatment altered DENV infection in the mosquito cells, suggesting that this pathway could be a possible antiviral mechanism in the mosquito system. Here we provide fundamental information needed to proceed with future experiments and to improve our understanding of the mosquito’s immune response against DENV.

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5. Receptor-like kinase BAM1 facilitates early movement of the Tobacco mosaic virus

   https://doi.org/10.1038/s42003-021-02041-0  

   Tran, Phu-Tri ; Citovsky, Vitaly ( April 2021 , Communications Biology)

   Cell-to-cell movement is an important step for initiation and spreading of virus infection in plants. This process occurs through the intercellular connections, termed plasmodesmata (PD), and is usually mediated by one or more virus-encoded movement proteins (MP) which interact with multiple cellular factors, among them protein kinases that usually have negative effects on MP function and virus movement. In this study, we report physical and functional interaction between MP ofTobacco mosaic virus(TMV), the paradigm of PD-moving proteins, and a receptor-like kinase BAM1 from Arabidopsis and its homolog fromNicotiana benthamiana. The interacting proteins accumulated in the PD regions, colocalizing withmore »a PD marker. Reversed genetics experiments, using BAM1 gain-of-function and loss-of-function plants, indicated that BAM1 is required for efficient spread and accumulation the virus during initial stages of infection of both plant species by TMV. Furthermore, BAM1 was also required for the efficient cell-to-cell movement of TMV MP, suggesting that BAM1 interacts with TMV MP to support early movement of the virus. Interestingly, this role of BAM1 in viral movement did not require its protein kinase activity. Thus, we propose that association of BAM1 with TMV MP at PD facilitates the MP transport through PD, which, in turn, enhances the spread of the viral infection.

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