alpha4-Fucosyltransferase is regulated during flower development: increases in activity are targeted to pollen maturation and pollen tube elongation.
alpha4-Fucosylation represents a final step of protein N- glycosylation. alpha4-fucosylated N-glycans are thought to be involved in cell-to-cell communication and recognition in primates and plants. Nevertheless, in the plant life cycle, the function of alpha4-fucosylation remains largely unknown. To gain an insight into the role of alpha4-fucosylation during development, the study focused on tobacco flowers. It is shown that an increase in alpha(1,4)fucosyltransferase (Fuc-T) activity is only observed during anther development, whereas it remains at a constant but low level (around 20 pmol Fuc h(-1) mg(-1) protein) in the gynoecium and perianth. At least a 4-fold higher activity is detected in mature pollen grains. These data suggest that alpha(1,4)Fuc-T activity is regulated during anther development. Furthermore, alpha(1,4)Fuc-T activity could be required during pollen tube elongation where the activity level peaks at 350 pmol h(-1) mg(-1) protein. Based on enzyme profile and cycloheximide effects on pollen germination and activity, it is hypothesized that the gene encoding alpha4-Fuc-T could be regulated late during pollen development. A potential role of alpha4- fucosylation during pollen tube elongation is also discussed.
Joly
Caroline
C
Glycobiologie et Biotechnologie EA3176, Institut des Sciences de la Vie et de la Santé, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges Cedex, France.
Léonard
Renaud
R
Maftah
Abderrahman
A
Riou-Khamlichi
Catherine
C
D002450:Cell Communication / Q000502:physiology; D003513:Cycloheximide / Q000494:pharmacology; D004789:Enzyme Activation; D005647:Fucosyltransferases / Q000378:metabolism*; D006031:Glycosylation; D018514:Plant Structures / Q000254:growth & development* / Q000378:metabolism; D011058:Pollen / Q000187:drug effects / Q000254:growth & development*; D012098:Reproduction / Q000502:physiology; D014026:Nicotiana / Q000254:growth & development / Q000378:metabolism
D003513:Cycloheximide; D005647:Fucosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase