Submitted to: Journal of Plant Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 17, 2006
Publication Date: January 3, 2006
Citation: Haagenson, D.M., Klotz, K.L., McGrath, J.M. 2006. Sugarbeet sucrose synthase genes differ in organ-specific and developmental expression. Journal of Plant Physiology. 163:102-106. Interpretive Summary: Sugarbeet has two genes that encode sucrose synthase, an enzyme that degrades sucrose in the root during production and postharvest storage. One gene was isolated and described in 1996. In this paper, we report the isolation of the second sucrose synthase gene and compare its structure and expression throughout development and in different plant organs. It is likely that the two genes serve different functions in the plant and are regulated differently. The purpose of this research is to provide information that will be useful towards understanding these differences.
Technical Abstract: A full length sucrose synthase (SBSS2) cDNA clone was isolated from sugarbeet and its structure, organ specific expression and developmental expression were characterized and compared to a previously isolated sugarbeet sucrose synthase gene (SBSS1). The two genes share 80% similarity in amino acid sequence but belong to different sucrose synthase subclasses based on phylogenic analysis. Both sucrose synthases were highly expressed in roots, and had low levels of expression in leaf tissue. Transcript abundance of SBSS2, relative to SBSS1, was greater in young vegetative tissues and reduced in mature tissue. Sucrose synthase protein accumulation mirrored steady-state mRNA levels suggesting that organ and developmental specific expression of sugarbeet sucrose synthase protein is largely regulated at the level of transcription.