Figure 6.

Expression patterns of unigenes encoding enzymes involved in starch and sucrose metabolism during SR development in three sweet potato genotypes. Cluster analysis was performed to group DEGs with similar expression levels and patterns based on the normalized log2-transformed RPKM values of DEGs. The abbreviations of enzymes and transporters encoded by DEGs are shown in Figure S2. GS, glycogen (starch) synthase (EC 2.4.1.11); IbAGPa1, IbAGPa2, IbAGPb1A, IbAGPb1B, IbAGPb2, ADP-glucose pyrophosphorylase (AGPase, EC 2.7.7.27) small subunit 1, 2, and large subunit 1, 2, and 3, respectively; IbβFRUCT2, β-fructofuranosidase (EC 3.2.1.26); INVInh, invertase inhibitor; SBEI and SBEII, class I and II starch branching enzyme (EC 2.4.1.18), respectively. Red, dark red, green, and pale green rectangles on the right side indicate DEGs involved in starch granule formation and degradation, sucrose metabolism, sucrose synthesis and conversion, and DEGs encoding transporters, respectively.