Comparative multi-omics profiling of Gossypium hirsutum and Gossypium barbadense fibers at high temporal resolution reveals key differences in polysaccharide composition and associated glycosyltransferases
Authors: Swaminathan, S., Lee, Y., Grover, C. E., DeTemple, M. F., Mugisha, A. S., Sichterman, L. E., Yang, P., Xie, J., Wendel, J. F., Szymanski, D. B., Zabotina, O. A.
The study performed daily large-scale glycome, transcriptome, and proteome profiling of developing fibers from the two cultivated cotton species, Gossypium barbadense and G. hirsutum, across primary and secondary cell wall stages. It identified delayed cellulose accumulation and distinct compositions of xyloglucans, homogalacturonans, rhamnogalacturonan‑I, and heteroxylans in G. barbadense, along with higher expression of specific glycosyltransferases and expansins, suggesting these molecular differences underlie the superior fiber length and strength of G. barbadense.
The study examined how tricarboxylic acid (TCA) cycle metabolites influence drought tolerance in grapevine and Arabidopsis, finding that malate uniquely triggers stomatal closure via elevations in cytosolic Ca2+ and activation of the SLAC1 anion channel. G-proteins were shown to be essential for malate‑mediated signaling, linking metabolic changes to drought response through a second‑messenger cascade.
The study developed a validated LC‑MS/MS method to simultaneously quantify fourteen polyamines, amino acids, and ethylene precursors in Arabidopsis thaliana and Solanum lycopersicum, and used it to compare their metabolic responses to drought, salinity, and inhibitor treatments. Distinct species‑specific metabolic adjustments were observed, with Arabidopsis showing greater fluctuations and drought generally increasing metabolite levels, while spermine exhibited stress‑specific patterns.