Humaniin – väike peptiid, suured ülesanded? Ülevaateartikkel humaniini-nimelisest peptiidist

Aastal 2001 kirjeldati esimest korda humaniini-nimelist peptiidi, mis võib olla esimene nn mitokondriaalne signaalmolekul. Praeguseks on kõnealusel peptiidil kirjeldatud mitmeid positiivseid omadusi: antiapoptootiline toime, tsütoprotektsioon mitmete mehhanismide kaudu. Peptiidi seostatakse vanusega seotud haigustega, näiteks diabeedi ja ateroskleroosiga. Artiklis on tutvustatud humaniini kui peptiidi, millest loodetakse potentsiaalset siirdemeditsiinilist läbimurret.Eesti Arst 2017; 96(6):328–33

Increased population growth rate in invasive polyploid Centaurea stoebe in a common garden

Biological invasions are inherently demographic processes, but trait differences between native and introduced genotypes are rarely linked to population growth rates. Native European Centaurea stoebe occurs as two cytotypes with different life histories (monocarpic diploids, polycarpic tetraploids); however, only tetraploids have been found in its introduced range in North America. In a common garden experiment using artificial populations, we compared the demographic performance of the three geo-cytotypes in the presence and absence of a specialist herbivore using periodic matrix models. We found no difference in population growth rate between the two European cytotypes and no significant effects of herbivory in all geo-cytotypes. However, there was a pronounced increase in population growth rate for North American compared with European tetraploids due to increased seed production and juvenile establishment. These results suggest that genetic drift or rapid evolution, rather than pre-adaptation through polyploidy may explain the invasion success of tetraploids