Climate Change Impacts on Broussonetia papyrifera Pollen - Metabolome Investigations and Prospects of Allergy Prevalence in Times of Climate Change

Abstract

Broussonetia papyrifera (B. papyrifera) is a tree producing allergenic pollen that grow at varied climatic conditions worldwide. The tree pollen disperse in the air causing allergies in susceptible humans. The study investigates climate change variable’s impact on B. papyrifera pollen’s composition, pollen metabolome, pollen allergenicity and their occurrence in the upcoming years. The tree pollens were collected in summer and spring from different regions in Pakistan. Pollens were subjected to morphological analysis, Fourier Transform Infrared Spectroscopy (FTIR), Liquid Chromatography-Mass Spectrometry (LCMS), and immunoblotting. The tree future-growth invasion was predicted through MaxEnt modeling. Light microscopy and FTIR showed seasonal and regional differences in pollen-morphology and pollen-metabolome that correlated to weather conditions’ shift. LCMS analysis detected four allergenic lipids having a potential role in allergies. Pollen protein immunoblotting-studies identified putative 15 kDa novel allergen, and verified previously known 40 kDa, 33 kDa, and 10 kDa allergens. B. papyrifera MaxEnt modeling through ACCESS1­0 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. The study findings demonstrate that climatic variables differences affect B. papyrifera-pollen physiology. The study discovered allergenic lipids and a 15 kDa potential novel allergen in B. papyrifera-pollen protein extracts, and predicted the tree invasion in future. These results predict potential changes in B. papyrifera-pollen allergy risks in the future and provide a model system for studying pollen morphology, plant invasion, and associated allergies in response to climate changes for other species.