Biology subjects

Prusinkiewicz, P.

Publications and source records attributed to Prusinkiewicz, P..

5 recordsLinked to original sources

bioRxiv2025

From spots to stripes: Evolution of pigmentation patterns in monkeyflowers via modulation of a reaction-diffusion system and its prepatterns

The reaction-diffusion (RD) system is widely assumed to account for many complex, self- organized pigmentation patterns in natural organisms. However, the specific configurations of such RD networks and how RD systems interact with positional information (i.e., prepatterns) that may specify the initiation conditions for the RD operation remain largely unknown. Here, we introduced a three-substance RD system underlying the formation of repetitive pigment spots and stripes in Mimulus flowers. It consists of an R2R3-MYB activator (NEGAN), an R3-MYB inhibitor (RTO), and a coactivator represented by two paralogous bHLH proteins. Through fine- scale genetic analyses, transgenic experiments, and computer simulations, we identified the causal loci contributing to the evolutionary transition from sparsely dispersed spots to longitudinal stripes. Genetic changes at these loci modulate the prepatterns of the activator and coactivator expression and the promoter activities of the inhibitor and one of the coactivator paralogs. Our findings highlight the importance of prepatterns towards a realistic description of RD systems in natural organisms, and reveal the genetic mechanism generating pattern variation through modulation of the kinetics of the RD system and its prepatterns.

developmental biology↗

bioRxiv2024

Reticulate leaf venation in Pilea peperomioides is a Voronoi diagram

Reticulate leaf venation, characterized by the presence of loops, is a distinguishing feature of many flowering plants. However, our understanding of both the geometry and the morphogenesis of reticulate vein patterns is far from complete. We show that in the Chinese money plant (Pilea peperomioides), major veins form an approximate Voronoi diagram surrounding secretory pores known as hydathodes. We also propose a mechanistic model based on polar transport of the plant hormone auxin to produce Voronoi patterns. In contrast with classical models where veins directly connect auxin sources to sinks, our model generates veins that bisect the space between adjacent auxin sources, collectively forming loops. The paradigm change offered by this model may open the door to study reticulate vein formation in other species.

plant biology↗

bioRxiv2023

The Hidden Diversity of Vascular Patterns in Flower Heads

O_LIVascular systems are intimately related to the shape and spatial arrangement of the plant organs they support. We investigate the largely unexplored association between spiral phyllotaxis and the vascular system in Asteraceae flowers heads. C_LIO_LIWe imaged heads of eight species using synchrotron-based X-ray micro-computed tomography and applied original virtual reality and haptic software to explore head vasculature in three dimensions. We then constructed a computational model to infer a plausible patterning mechanism. C_LIO_LIThe vascular system in the head of the model plant Gerbera hybrida is qualitatively different from those of Bellis perennis and Helianthus annuus, characterized previously. Cirsium vulgare, Craspedia globosa, Echinacea purpurea, Echinops bannaticus, and Tanacetum vulgare represent variants of the Bellis and Helianthus systems. In each species the layout of the main strands is stereotypical, but details vary. The observed vascular patterns can be generated by a common computational model with different parameter values. C_LIO_LIIn spite of the observed differences of vascular systems in heads, they may be produced by a conserved mechanism. The diversity and irregularities of vasculature stand in contrast with the relative uniformity and regularity of phyllotactic patterns, confirming that phyllotaxis in heads is not driven by the vasculature. C_LI

plant biology↗

bioRxiv2022

Diversity of the woodland strawberry inflorescences results from heterochrony antagonistically regulated by FvTFL1 and FvFT1

A vast variety of inflorescence architectures have formed during angiosperm evolution. Here we analyze the diversity and development of the woodland strawberry inflorescence. We show that it is a thyrse: a compound inflorescence in which the primary monopodial axis supports lateral sympodial branches, thus combining features of racemes and cymes. We demonstrate that this architecture is related to differences in the size and shape of the primary and lateral inflorescence meristems. We further show that woodland strawberry homologs of TERMINAL FLOWER 1 (TFL1) and FLOWERING LOCUS T (FT) antagonistically regulate the development of both the racemose and cymose components of the strawberry thyrse: the loss of functional FvTFL1 and overexpression of FvFT1 reduce the number and complexity of the cymose components, whereas silencing of FvFT1 has the opposite effect and can partially rescue the fvtfl1 mutation. We complement our experimental findings with a computational model, which captures the development of the woodland strawberry inflorescence using a small set of rules, and shows that its phenotypic diversity can be explained in terms of heterochrony resulting from the opposite action of FvTFL1 and FvFT1 on the progression from the branching to flowering state.

plant biology↗

bioRxiv2019

Latent Space Phenotyping: Automatic Image-Based Phenotyping for Treatment Studies

Association mapping studies have enabled researchers to identify candidate loci for many important environmental resistance factors, including agronomically relevant resistance traits in plants. However, traditional genome-by-environment studies such as these require a phenotyping pipeline which is capable of accurately and consistently measuring stress responses, typically in an automated high-throughput context using image processing. In this work, we present Latent Space Phenotyping (LSP), a novel phenotyping method which is able to automatically detect and quantify response to treatment directly from images. Using two synthetically generated image datasets, we first show that LSP is able to successfully recover the simulated QTL in both simple and complex synthetic imagery. We then demonstrate an example application of an interspecific cross of the model C4 grass Setaria. We propose LSP as an alternative to traditional image analysis methods for phenotyping, enabling association mapping studies without the need for engineering complex image processing pipelines.

plant biology↗