Gibberellin-Induced Gene Expression Associated with Cytoplasmic Male Sterility in Sunflower

Abstract

Gibberellins (GAs) are plant hormones with diverse roles in plant growth and development. Male sterility is one of several GA responses. In an effort to understand the involvements of GAs in sunflower male reproductive development, physiological, biochemical and molecular studies of GA-induced and cytoplasmic male sterility were performed. Male sterility was induced by exogenous application of gibberellic acid (GA3) to the fertile inflorescence apex in early reproductive development. Using different experimental approaches: hormonal quantitative analyses (gas-liquid chromatography), protein profiles (SDS PAGE) and transcripts assays (RT-PCR) revealed a similarity in expression of cytoplasmic (CMS) and induced (IMS) male sterility. Our results provide the first evidence that expression of CMS-specific orfH522 gene can be induced by GA3 in plant with original fertile cytoplasm.