SRD1 is involved in the auxin-mediated initial thickening growth of storage root by enhancing proliferation of metaxylem and cambium cells in sweetpotato (Ipomoea batatas)

摘要: A sweetpotato (Ipomoea batatas cv. ‘Jinhongmi’) MADS-box protein cDNA (SRD1) has been isolated from an early stage storage root library. The role of the SRD1 gene in formation was investigated by expression pattern analysis and characterization SRD1-overexpressing (ox) transgenic plants. Transcripts were detected only tissues, with fibrous having low levels transcript young showing relatively higher levels. mRNA mainly found actively dividing cells, including vascular cambium cells root. level roots increased response to 1000 mM indole-3-acetic acid (IAA) applied exogenously. During development, endogenous IAA content concomitantly, suggesting involvement during auxin-dependent development SRD1-ox plants cultured vitro produced thicker shorter than wild-type metaxylem showed markedly enhanced proliferation, resulting these earlier thickening growth those Taken together, results demonstrate that plays a activating proliferation induce initial manner.