30 research outputs found
Lateral transfers of large DNA fragments spread functional genes among grasses
A fundamental tenet of multicellular eukaryotic evolution is that vertical inheritance is paramount, with natural selection acting on genetic variants transferred from parents to offspring. This lineal process means that an organism's adaptive potential can be restricted by its evolutionary history, the amount of standing genetic variation, and its mutation rate. Lateral gene transfer (LGT) theoretically provides a mechanism to bypass many of these limitations, but the evolutionary importance and frequency of this process in multicellular eukaryotes, such as plants, remains debated. We address this issue by assembling a chromosome-level genome for the grass Alloteropsis semialata, a species surmised to exhibit two LGTs, and screen it for other grass-to-grass LGTs using genomic data from 146 other grass species. Through stringent phylogenomic analyses, we discovered 57 additional LGTs in the A. semialata nuclear genome, involving at least nine different donor species. The LGTs are clustered in 23 laterally acquired genomic fragments that are up to 170 kb long and have accumulated during the diversification of Alloteropsis. The majority of the 59 LGTs in A. semialata are expressed, and we show that they have added functions to the recipient genome. Functional LGTs were further detected in the genomes of five other grass species, demonstrating that this process is likely widespread in this globally important group of plants. LGT therefore appears to represent a potent evolutionary force capable of spreading functional genes among distantly related grass species
The East India CompanyâsFarmÄn, 1622â1747
The East India Companyâs presence and ongoing trade in Persia was reliant on the privileges outlined in the FarmÄn, granted after the capture of Hormuz in 1622. The relationship between these two powers was cemented in the rights enshrined in the FarmÄn, which was used by both to regulate their varying needs and expectations over the course of 125 years. This article explores the Companyâs records of the FarmÄn and how changes to its terms were viewed from both sides. As a Persian document, the FarmÄn gives a clear view of the attitudes of native officials and rulers to the Company and how these terms were used as a means of control