Fig. 4

Annotation and functional classification of the DEGs. a Histogram of Gene Ontology (GO) classifications of the DEGs in paper mulberry under cold stress. Total 5043 DEGs could be annotated by GO and they mainly distributed in metabolic process, response to stimulus, catalytic, binding and organelle belonged to Biological process, Cellular components and Molecular function, respectively. b The number of DEGs in each COG functional classification group. A total of 1,851 DEGs had been annotated by COG. Except the function prediction only and function unkown, group O (Posttranslational modification, protein turnover, and chaperones), J (Translation, ribosomal structure and biogenesis), G (carbohydrate metabolism), C (energy production), E (amino metabolism), P (inorganic ion transport and metabolism), I (lipid metabolism) and Q (secondary metabolism) took up more than half of the total DEGs annotated in COG. c The statistics analysis of DEGs mapped to KEGG pathways