Overview of Pinus tabuliformis transcriptome sequencing and assembly. (a) Frequency distribution of 454 sequencing read lengths after filtering and trimming adapters. (b) Length distributions for isotigs and singlets following the de novo assembly process. The abscissa has been truncated at 2 kb. The longest isotig was 3,537 base pairs. An isotig is meant to be analogous to an individual transcript. (c) The average read-depth coverage for assembled unigenes. The y-axis label refers to the total length of all unigenes with the same read-depth coverage. Coverage values from 50 to 6,765 have been binned together. The size of the bubble is proportional to the average unigene length at the corresponding read-depth coverage. (d) A density scatter-plot showing the relationship between unigene length and coverage.
Niu et al. BMC Genomics 2013 14:263 doi:10.1186/1471-2164-14-263