Abstract
Background: Upland cotton ( Gossypium hirsutum L.) is one of the most economically important crops worldwide . Cottonseed is a major significant source of fiber, feed, foodstuff, oil and biofuel products. However, the utilization of cottonseed is 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,some progress has been made in the pigment gland formation, but the underlying molecular mechanism of pigment gland formation was still unclear. Results: In this study, we identified an AP2/ERF transcription factor named GhERF105 (Gh_A12G1784), which is involved in the regulation of gland pigmentation, from comparative transcriptome analysis of the leaf transcriptome from two pairs of glanded and glandless accessions, which are CCRI12 and CCRI12XW, L7 and L7XW. This gene encoded an ERF protein containing a converved AP2 domain localized in the nucleus with transcriptional activity., and it showed the high expression in glanded cotton accessions that contained much gossypol. Virus-induced gene silencing(VIGS) 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 contributes to the pigment gland formation and gossypol biosynthesis in partial organs of glanded plant. It also provides a potential molecular basis to generate ‘glandless-seed’ and ‘glanded-plant’ cotton cultivar.
Expression of the “glanded-plant and glandless-seed” trait of Australian diploid cottons in different genetic backgrounds
