Transcriptomic analyses reveal the potential regulators of the storage root skin color in sweetpotato

Sweetpotato (Ipomoea batatas (L.) Lam.) is an important storage root crop exhibiting diverse storage root skin and flesh colors across varieties. The storage root skin color (SRSC) is a vital commercial trait which significantly influences the marketability and consumer preference of sweetpotato. To clarify the regulatory mechanism of SRSC, the storage root of sweetpotato line M1-125 and its natural mutant were sampled and transcriptomic sequenced in this study. Overall design: The wild type line M1-125 and its natural mutant MT were planted in the modern agricultural experimental farm of the Xuzhou sweetpotato research. The flesh and skin of their storge root were sampled with three biological replicates at 120 DAP (days after planting), then washed and cut into small pieces. All samples were immediately frozen in liquid nitrogen and subsequently stored at -80 °C for RNA extraction and library construction.Total RNA was prepared from flesh and root skin samples using TRIzol reagent kit (Invitrogen, Carlsbad, CA, USA). The concentration and integrity of RNA were measured by an Agilent 2100 bioanalyzer (Agilent Technologies, Palo Alto, CA, USA) and RNase-free agarose gel electrophoresis, respectively. Following the removal of rRNA using the Ribo-ZeroTM Magnetic Kit (Epicentre, Madison, WI, USA), the mRNA was enriched by Oligo (dT) beads. The completed mRNA was then used for library construction following the manufacturer's protocol of NEBNext Ultra RNA Library Prep Kit for Illumina (NEB #7530, New England Biolabs, Ipswich, MA, USA). All mRNA-seq libraries were sequenced on Illumina NovaSeq 6000 platform in Gene Denovo Biotechnology Company, Guangzhou, China.