Molecular cloning and characterization of GhERF105, a gene participated in the regulation of gland formation from cotton (Gossypium hirsutum L.)
Abstract Background Gossypium hirsutum L. (cotton) is one of the most economically important crops globally. Cottonseed is the significant source of fiber, feed, foodstuff, oil and biofuel products. However, the utilization of cottonseed was limited by the presence of small and darkly pigmented glands that contain large amounts of gossypol, which is toxic to human beings and other non-ruminant animals. To date, there has been some progress in the pigment gland formation, but the underlying molecular mechanism of pigment gland formation was still complicated and unclear. Results In this study, we identified an AP2/ERF transcription factor named GhERF105 (Gh_A12G1784), which was involved in the regulation of gland pigmentation, from comparative transcriptome analysis of the leaf of two pairs of glanded and glandless accessions, which are CCRI12 and CCRI12XW, L7 and L7XW. It encoded an ERF protein localized in the nucleus with transcriptional activation activity containing a conserved AP2 domain, and showed the high expression in glanded cotton accessions that contained much gossypol. Virus-induced gene silencing against GhERF105 caused the dramatic reduction in the number of glands and significantly lowered levels of gossypol in cotton leaves. GhERF105 showed the patterns of spatiotemporal and inducible expression in the glanded plants. Conclusions These results suggest that GhERF105 participates in the pigment gland formation and gossypol biosynthesis in partial tissue of glanded plant. It also provides a potential molecular basis to generate ‘glandless-seed’ and ‘glanded-plant’ cotton cultivar.