Biology subjects

Boehnert, T.

Publications and source records attributed to Boehnert, T..

3 recordsLinked to original sources

bioRxiv2026

Muscari commutatum genome sequences reveal genetic basis of flower pigmentation

Flower colour is an important component of floral signaling, yet the genetic basis of naturally occurring colour variation remains poorly understood in many non-model plant groups. Here, we compare genome sequences of a normally pigmented and a largely unpigmented individual of Muscari commutatum, a species typically characterized by very dark violet flowers. Both assemblies were approximately 3.5 Gbp in size, with contig N50 values exceeding 130 Mbp and BUSCO completeness of about 99%. Most structural genes of the flavonoid biosynthesis and the corresponding transcriptional regulators were identified in both plants. Strikingly, no flavanone 3-hydroxylase (F3H) gene was detected in the genome sequence of the unpigmented plant, and additional manual searches provided no evidence for a bona fide F3H copy. Comparison of the two genome sequences revealed a lack of local synteny around the F3H locus of the anthocyanin-pigmented plant, suggesting that F3H might have been lost in the unpigmented plant in association with a genomic rearrangement.

plant biology↗

bioRxiv2023

Genome-wide SNP data reveal recent population structure of Huidobria fruticosa (Loasaceae), a paleo-endemic lineage from the Atacama Desert

The Atacama Desert is a biodiversity hotspot of neo-endemic radiation, where long-term aridity and complex physiographic processes create a unique environmental setting. Current species assemblages are mainly concentrated in highly patchy loma formations, and plant populations occurring in these are often geographically isolated from each other. Despite a general consensus on long-term aridity in the Atacama, climatological and geological evidence points to repeated climate change, making the Atacama Desert an ideal system for studying population genetic processes in highly unstable habitats. We are analyzing the genetic structure within and between populations of Huidobria fruticosa, a paleo-endemic lineage of the Atacama Desert, to shed new light on its biogeographic history and broaden our understanding of the evolution of life in extreme aridity, as well as plant evolution in response to a changing environment. To do this, we analyzed SNP data from genotyping-by-sequencing of 354 individuals from 21 populations. Our results suggest that, despite being an ancient lineage, the current population structure of Huidobria fruticosa only reflects changing abiotic conditions over the last 2 million years. We therefore conclude that the present distribution, together with the evolutionary processes documented here, is the result of climatic fluctuations and prolonged periods of hyperaridity during the Pleistocene. Building on this understanding, our findings contribute to a global narrative that highlights the complex interplay between climate change and evolutionary dynamics, and emphasize the importance of deserts as living laboratories for deciphering how species have historically adapted to some of the most extreme habitats on Earth.

evolutionary biology↗

bioRxiv2023

Genetic diversity of the Atacama Desert shrub Huidobria chilensis in the context of geography and climate

Survival in hyperarid deserts is a major challenge for plant life, requiring the development of evolutionary strategies. The Atacama Desert presents harsh conditions such as limited rainfall, crusted soils, high soil salinity, high altitude, and intense solar radiation. These conditions, together with paleoclimatic variability since the past millions of years, have influenced the genetic structure and connectivity of plant populations, resulting in a diverse flora with high endemism. However, the diversification of most lineages appears to be relatively recent, in contrast to proposed age of the Atacama Desert and the onset, evolution and expansion of hyperarid conditions since the Late Oligocene and Early Miocene. A prominent exception is the Atacama paleoendemic Huidobria chilensis (Loasaceae), which is thought to be adapted to such conditions since the Eocene. Still, the environmental limits and thresholds for life in the Atacama remain poorly understood. To investigate the genetic structure in relation to the history of the Atacama Desert, we studied 186 individuals from 11 populations using genotyping-by-sequencing (GBS). Genome-wide single nucleotide polymorphisms (SNPs) were analyzed for population structure and genetic diversity. We identified three genetic clusters corresponding to geographic regions: the coastal region south of Tocopilla, the Coastal Cordillera around Chanaral, and the Copiapo watershed in the south. These clusters as well as genetic diversity were analyzed alongside rainfall, altitude, and landscape data. Although the genetic data generally supports isolation by distance as a major factor for genetic variation between populations, the study also reveals the influence of the topography on the distribution of H. chilensis and highlights the role of hydrologically connected watersheds and rivers in plant migration and colonization. This shapes the species evolutionary trajectory and genetic diversity. Understanding these patterns provides insights into the adaptation and survival strategies of plants in extreme desert environments such as the Atacama.

genetics↗