Transcriptional differences between repeatedly recultured and freshly induced embryogenic calli reveal candidate developmental regulators

RNA-seq of peanut (Arachis hypogaea L.) embryogenic calli shows distinct transcriptional programs between new callus (NC, 3 months) and old callus (OC, 4 years), with 1,141 and 2,086 upregulated genes, respectively.

• Why it matters: Genotype dependence and long tissue-culture steps hinder peanut transformation, so molecular regulators of callus development and proliferation are needed to guide improved regeneration systems.
• What they did: Georgia Green calli were maintained for three months or repeatedly subcultured for four years, then compared by RNA sequencing; qRT-PCR of seven genes corroborated results (r = 0.944; R2 = 0.891).
• The result: Differentially expressed transcription factors and highly upregulated candidates (including AP2/ERF, WOX, GRAS, LBD, NAC members and SWEET sugar transporters) provide a resource to prioritize developmental regulators for functional validation.