If you only have RNAseq results, you may want to try if GeneNetworkBuilder could build a network for differential expressed gene. Here is the sample code for that.
library(GeneNetworkBuilder)
try({ ## just in case STRINGdb not work
library(STRINGdb)
string_db <- STRINGdb$new( version="10", species=9606,
score_threshold=400)
data(diff_exp_example1)
example1_mapped <- string_db$map( diff_exp_example1, "gene", removeUnmappedRows = TRUE )
i <- string_db$get_interactions(example1_mapped$STRING_id)
colnames(example1_mapped) <- c("gene", "P.Value", "logFC", "symbols")
## get significant up regulated genes.
genes <- unique(example1_mapped$symbols[example1_mapped$P.Value<0.005 & example1_mapped$logFC>3])
x<-networkFromGenes(genes = genes, interactionmap=i, level=3)
## filter network
## unique expression data by symbols column
expressionData <- uniqueExprsData(example1_mapped,
method = 'Max',
condenseName = "logFC")
## merge binding table with expression data by symbols column
cifNetwork<-filterNetwork(rootgene=x$rootgene,
sifNetwork=x$sifNetwork,
exprsData=expressionData, mergeBy="symbols",
miRNAlist=character(0),
tolerance=1, cutoffPVal=0.001, cutoffLFC=1)
## convert the id back to symbol
IDsMap <- expressionData$gene
names(IDsMap) <- expressionData$symbols
cifNetwork <- convertID(cifNetwork, IDsMap)
## polish network
gR<-polishNetwork(cifNetwork)
## browse network
browseNetwork(gR)
})
## ERROR: Currently STRINGdb only supports the most recent version of STRING: 11.0Error in .Object$initialize(...) :