Hi, I'm trying to change the font size of the gene name and increase the arrow head size. I've tried changing the cex and cex.id but it does'nt seem to be effecting the font size; for example below I set both to 30 with no observable differences. The question is I'm trying to change the arrow head size, however lwd only changes the thickness of the line and not so much the arrow head. Can anyone help? thanks in advance.

rTrack <- UcscTrack(genome=gen, chromosome=chrom, track="NCBI RefSeq", 
                    from=minbase, to=maxbase, trackType="GeneRegionTrack", 
                    rstarts="exonStarts", rends="exonEnds", gene="name", 
                    symbol="name2", transcript="name", strand="strand", 
                    fill="darkblue",stacking="squish", name="RefSeq", cex.title=2.8,
                    cex =30,  # does not change gene name 
                    cex.id = 30, # does not change gene name
                    lwd = 2.2, # only changes thickness but not the size of the arrow head. 
                    showId=TRUE, geneSymbol=TRUE )

edit: I figure out how to change the size of the name but the little directional grey arrows is still a mystery.

displayPars(rTrack) <- list(fontsize = 15) # changes size of genes