Spike Activator 1, Encoding a bHLH, Mediates Axillary Bud Development and Spike Initiation in Phalaenopsis aphrodite.

ABSTRACT: Double-spikes Phalaenopsis orchids have greater market value than those with single-spike. In this study, a gene designated as Spike Activator 1 (SPK1), which encodes a basic helix-loop-helix (bHLH) transcription factor, was isolated and characterized from Phalaenopsis aphrodite (moth orchid). SPK1 was highly expressed in the meristematic tissues. In the axillary bud, SPK1 was highly upregulated by a moderately low temperature of 20 °C but downregulated by a spike inhibition temperature of 30 °C. SPK1 protein is localized in the nucleus. Another bHLH, bHLH35, which is also highly expressed in young tissues in the same way as SPK1 was also identified. In contrast to SPK1, bHLH35 transcripts are downregulated at 20 °C but

SUBMITTER: Lin YJ 

PROVIDER: S-EPMC6862315 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature