Urbanization extends flight phenology and leads to local adaptation of seasonal plasticity in Lepidoptera

Urbanization is gaining force globally, which challenges biodiversity, and it has recently also emerged as an agent of evolutionary change. Seasonal phenology and life cycle regulation are essential processes that urbanization is likely to alter through both the urban heat island effect (UHI) and artificial light at night (ALAN). However, how UHI and ALAN affect the evolution of seasonal adaptations has received little attention. Here, we test for the urban evolution of seasonal life-history plasticity, specifically changes in the photoperiodic induction of diapause in two lepidopterans, Pieris napi (Pieridae) and Chiasmia clathrata (Geometridae). We used long-term data from standardized monitoring and citizen science observation schemes to compare yearly phenological flight curves in six cities in Finland and Sweden to those of adjacent rural populations. This analysis showed for both species that flight seasons are longer and end later in most cities, suggesting a difference in the timing of diapause induction. Then, we used common garden experiments to test whether the evolution of the photoperiodic reaction norm for diapause could explain these phenological changes for a subset of these cities. These experiments demonstrated a genetic shift for both species in urban areas toward a lower daylength threshold for direct development, consistent with predictions based on the UHI but not ALAN. The correspondence of this genetic change to the results of our larger-scale observational analysis of in situ flight phenology indicates that it may be widespread. These findings suggest that seasonal life cycle regulation evolves in urban ectotherms and may contribute to ecoevolutionary dynamics in cities.

A genetic shift in an escaped transmitted/founder virus guides combinatorial vaccine design against HIV-1

A productive HIV-1 infection is often established by a single transmitted/founder (T/F) virus, which then evolves into a complex mixture of variants during the lifetime of infection. An effective vaccine should have sufficient breadth to block the entry of diverse T/F involved in different infections. Although the variable V1V2 domain of HIV-1 envelope protein (Env) is found to be a good target for vaccine design based on the correlates of protection in the modestly successful RV144 trial, the breadth of immune responses has to be substantially enhanced to improve vaccine efficacy and minimize the emergence of breakthrough infections. Here, we report a remarkable genetic shift in a T/F virus from a participant of an acute HIV infection cohort_RV217 study. It resulted in substitution of histidine at position 173 to tyrosine (H173Y) at week 24 (wk 24) after infection, coinciding with the disappearance of strictly H173-specific first wave antibodies. Intriguingly, a second wave antibodies emerged against the escaped Y173 variant that displayed increased breadth recognizing both the H173 and Y173 epitopes. This differential antibody responses towards variant epitopes were recapitulated in a mouse model. Structural analyses suggest distinct conformations for H173 and Y173 variants which might have led to antibody responses with different reactivity and breadth. Given the occurrence of conformational dynamism in the V2 region, combinatorial V2 vaccine candidates consisting of numerous conformational variants in the natural HIV-1 diversity were designed and tested as an immunogen. These libraries, especially the Y173 variant libraries that also contained a V1 loop deletion showed increased breadth and cross-reactivity to diverse HIV-1 Env proteins. This combinatorial design might be a powerful strategy in the future design of highly efficacious HIV-1 vaccine candidates.

Identifying morphological traits associated with vegetative persistence in the perennial ryegrass (Lolium perenne L.) cultivar 'Grasslands Samson'

Perennial ryegrass (Lolium perenne L.) vegetative persistence (maintained herbage growth and survival without reseeding) is an important economic trait for farmers in New Zealand as it decreases the frequency of reseeding pastures. Vegetative persistence is difficult to breed for due to a lack of long-term trials to observe the complex interactions between plant genotype and the environment. In a long-term trial a genetic shift in the sown cultivar population could occur as individual plants with advantageous traits outcompete other plants and survive. The objectives of our study were to investigate the occurrence of a potential genetic shift in a sample (30 plants) of a persistent population of ‘Grasslands Samson’ perennial ryegrass. Persistent plants were collected from a nine-year-old trial at Poukawa, Hawke's Bay. To identify a genetic shift, these plants were compared to a sample of 30 plants sourced from commercial seed of ‘Grasslands Samson’ representing the original population. This study estimated genotypic variation within and between the populations for eight morphological traits after 10 weeks' growth under glasshouse conditions. Phenotypic and genotypic correlations between the traits were estimated. Results showed that the persistent population had significantly (P<0.05) greater means for tiller number, reproductive tiller number, lamina sheath length, and dry weight. Future research studying these traits across farm environments would further understanding of their roles in vegetative persistence of ryegrass.

Possible treatments of COVID-19 present and future

Since the outbreak of COVID-19 infection in December 2019, millions of people are infected, and thousands of people have died. Genetic shift and high infectivity rate made SARS-Cov-2 a pandemic. Doctors, researchers, and world leaders are scratching their heads, how to contained or treat the virus. Several treatment options are tried, but so far, there is no effective treatment available. Thousands of articles are published about COVID-19, and so much information is available that it is challenging for a practicing physician to review these articles in the limited time they have. This article summarized the treatment options for COVID-19 that have tried or are in clinical trials. The article also reviews other possibilities that are either briefly or not discussed in the literature but could play a role in the fight against COVID-19.

Human mitochondrial DNA lineages in Iron-Age Fennoscandia suggest incipient admixture and eastern introduction of farming-related maternal ancestry

Human ancient DNA studies have revealed high mobility in Europe’s past, and have helped to decode the human history on the Eurasian continent. Northeastern Europe, especially north of the Baltic Sea, however, remains less well understood largely due to the lack of preserved human remains. Finland, with a divergent population history from most of Europe, offers a unique perspective to hunter-gatherer way of life, but thus far genetic information on prehistoric human groups in Finland is nearly absent. Here we report 103 complete ancient mitochondrial genomes from human remains dated to AD 300–1800, and explore mtDNA diversity associated with hunter-gatherers and Neolithic farmers. The results indicate largely unadmixed mtDNA pools of differing ancestries from Iron-Age on, suggesting a rather late genetic shift from hunter-gatherers towards farmers in North-East Europe. Furthermore, the data suggest eastern introduction of farmer-related haplogroups into Finland, contradicting contemporary genetic patterns in Finns.

Antigenic and genetic characterization of Bordetella pertussis recovered from Quebec, Canada, 2002–2014: detection of a genetic shift

Despite vaccination, cyclical peaks of Bordetella pertussis incidence rates are still observed in Canada and other developed countries, making pertussis one of the most prevalent vaccine preventable bacterial diseases. In the postacellular vaccine era, evolution of bacterial strains has resulted in strains with altered vaccine antigens. Previous Canadian studies have focused on isolates mainly from the provinces of Ontario and Alberta, with only small numbers of isolates from other provinces. Therefore, in this study, we examined a larger sample (n = 52) of isolates from Quebec, Canada, between 2002 and 2014. Isolates were characterized by serotype, sequence type, and prevalence of pertactin deficiency. The Quebec isolates shared characteristics similar to other Canadian isolates and to isolates circulating globally. Although pertactin-deficient isolates were not present, a significant shift in sequence type was observed in more recent years. This study highlights the importance of continually monitoring disease-causing isolates to track evolutionary trends and gain a better understanding of the molecular epidemiology of pertussis in Canada.