# Broussonetia papyrifera Pollen Metabolome Insights, Allergenicity, and Dispersal in Response to Climate Change Variables

## TL;DR

This study explores how climate change affects the pollen of Broussonetia papyrifera, including its allergenic potential and future spread.

## Contribution

The study identifies a novel allergen and links climate change to shifts in pollen metabolome and future plant invasion.

## Key findings

- Regional differences in pollen morphology and metabolome correlate with climatic variables.
- Four lipids were detected that may stimulate inflammatory responses.
- A putative 15 kDa novel allergen was identified alongside known allergens.

## Abstract

Background/Objectives: Broussonetia papyrifera is a tree-producing allergenic pollen that grows in varied climatic conditions worldwide and causes pollen allergies in susceptible humans. This study aimed to investigate B. papyrifera pollen morphology, pollen metabolome, pollen allergenicity, and climate change’s impact on the plant habitat suitability in the future. Methods: Tree pollen was collected in spring from different regions of Pakistan. Pollen samples were subjected to morphological analysis, Fourier transform infrared spectroscopy (FTIR), liquid chromatography–mass spectrometry (LC-MS/MS), and immunoblotting. Results: MaxEnt modeling predicted the tree’s future-growth invasion into new regions. Scanning electron microscopy (SEM) and FTIR displayed regional differences in pollen morphology and metabolome correlated to shifts in climatic variables. LC-MS/MS analysis detected four lipids that can potentially stimulate inflammatory responses. Pollen protein immunoblotting studies identified a putative 15 kDa novel allergen and verified previously known 40 kDa, 33 kDa, and 10 kDa allergens. B. papyrifera MaxEnt modeling through ACCESS1.0 and CCSM4 under 2-greenhouse gas emissions scenarios {representative concentration pathway (RCP) 4.5 and 8.5} projected the tree invasion by the years 2050 and 2070. Conclusions: The study findings demonstrate that differences in climatic variables affect B. papyrifera-pollen metabolome and predict the habitat suitability of the tree for invasion in the future. The study results provide a model system for studying other species’ pollen morphology, metabolome, future habitat suitability for plant invasion, and associated allergies in response to climate change.