Sexual reproductive success is critical for the production of seeds and is therefore essential for agricultural productivity. However, pollen development is highly sensitive to environmental events such as heat and frost, which can decimate crops.1 The overarching aim of this study was to investigate cotton (Gossypium hirsutum) pollen throughout the reproductive cycle by analysing proteomes at four distinct stages of development. Pollen grains were isolated from the gametophytic phases of development including tetrads, uninucleate and binucleate microspores and mature pollen. Using a phenol extraction method, in-solution digestion and LC-MS analysis, a library consisting of 5257 G. hirsutum proteins was constructed from all four developmental stages. SWATH-MS was used to quantify 4501 proteins and indicated that some proteins are stage specific and are associated with the development processes including those involved in the biosynthesis of secondary metabolites, carbon metabolism, biosynthesis of amino acids, protein processing in the endoplasmic reticulum, and glycolysis. We conclude that developing pollen cells have qualitatively distinct protein profiles at each stage. Proteins identified at the tetrad stage are particularly unique, and indicate that the earliest stage of cotton pollen development requires the synthesis of cellular components that enable subsequent mitoses and structural changes to the haploid germ cells.
1.Hatfield, J. L., Prueger J. H. (2015), Temperature extremes: Effect on plant growth and development, Weather and Climate Extremes, 10 (A), 4-10.