Genome-wide characterization and expression analysis of geranylgeranyl diphosphate synthase genes in cotton(Gossypium spp.)in plant development and abiotic stresses

Background GGPP (geranylgeranyl diphosphate) is produced in the isoprenoid pathway and mediates the function of various plant metabolites, which is synthesized by GGPPS (GGPP synthases) in plants.GGPPScharacterization has not been performed in any plant species exceptArabidopsis thaliana. Here, we performed a complete computational and bioinformatics analysis ofGGPPSand detected their transcription expression pattern inGossypium hirsutumfor the first time so that to explore their evolutionary relationship and potential functions. Finally, we unravelled evolutionary relationship, conserved sequence logos, gene duplication and potential involvement in plant development and abiotic stresses tolerance ofGGPPSgenes inG. hirsutumand other plant species. Results A total of 159GGPPSgenes from 18 plant species were identified and evolutionary analysis divided theseGGPPSgenes into five groups to indicate their divergence from a common ancestor. Further,GGPPSfamily genes were conserved during evolution and underwent segmental duplication. The identified 25GhGGPPSgenes showed diverse expression pattern particularly in ovule and fiber development indicating their vital and divers roles in the fiber development. Additionally,GhGGPPSgenes exhibited wide range of responses when subjected to abiotic (heat, cold, NaCl and PEG) stresses and hormonal (BL, GA, IAA, SA and MeJA) treatments, indicating their potential roles in various biotic and abiotic stresses tolerance. Conclusions TheGGPPSgenes are evolutionary conserved and might be involve in different developmental stages and stress response. Some potential key genes (e.g.GhGGPP4, GhGGPP9,andGhGGPP15) were suggested for further study and provided valuable source for cotton breeding to improve fiber quality and resistant to various stresses.