Abstract
O-GlcNAc transferase (OGT) catalyses transfer of GlcNAc (N-acetylglucosamine) to serine or threonine of proteins. The Arabidopsis OGTs, SECRET AGENT (SEC) and SPINDLY (SPY) have overlapping functions during gametogenesis and embryogenesis. SPY functions in a number of processes including circadian, light, and gibberellin (GA) responses. The role of SEC in plant development and GA signalling was investigated by determining the phenotypes of sec-1 and sec-2 plants and the expression pattern of SEC. Similar to SPY, SEC transcripts were ubiquitous. Although there is no evidence of transcript-level regulation by other factors, SEC mRNA levels are elevated in spy plants and SPY mRNA levels are elevated in sec plants. sec-1 and sec-2 plants exhibited few of the defects observed in spy plants and had wild-type GA responses. Compared with wild type, sec plants produced leaves at a reduced rate. Haplo-insufficiency at SEC in a spy ga1 double mutant background suppressed spy during germination and enhanced the production of ovaries with four carpels by spy. By contrast, SPY haplo-insufficiency in a sec ga1 double mutant background caused a novel phenotype, production of a proliferation of pin-like structures instead of a floral shoot. These results are consistent with SEC function overlapping with SPY for leaf production and reproductive development.
Original language | English (US) |
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Pages (from-to) | 865-875 |
Number of pages | 11 |
Journal | Journal of experimental botany |
Volume | 57 |
Issue number | 4 |
DOIs | |
State | Published - Mar 2006 |
Bibliographical note
Funding Information:We are grateful for the help of Patricia Gordon, Saba Zafari, and Dr David Marks for assistance with experiments. This work was supported by the National Science Foundation grant (MCB-0112826) to NEO and by the US Department of Energy grant (DE-FG01-04ER04) to NEO and LMH.
Keywords
- Flowering time
- O-GlcNAc
- O-glycosylation
- Shoot apical meristem