Abstract

Microdistribution of mannans in Arabidopsis stem was examined using immunolocalization with mannan-specific monoclonal antibodies (LM21 and LM22). Mannan labeling in secondary xylem cells (except for protoxylem vessels) was initially detected in the cell wall during S-2 formation and increased gradually during development. Labeling in metaxylem vessels (vessels) was detected earlier than that in xylary fibers (fibers), but was much weaker than fibers. The S-1 layer of vessels and fibers showed much less labeling than the S-2 layer. Some strong labeling was also detected in pit membranes of vessel pits. Interfascicular fibers (If-fibers) showed more heterogeneous labeling patterns than fibers by LM21. Unlike fibers, If-fibers also revealed some strong labeling in the cell corner of the S-1 layer, indicating different mannan labeling patterns between If-fibers and fibers. Interestingly, protoxylem vessels (proto-vessels) showed strong labeling at the early stage of secondary xylem formation with more intense labeling in the outer- than inner cell wall even though fibers and vessels showed no or very low labeling at this stage. Labeling intensity of proto-vessels was also much stronger than vessels and stronger or slightly weaker than fibers by LM21 and LM22, respectively. Using pectinase and mild alkali treatment, the presence of mannans in parenchymatous cells was also confirmed. Together our observations indicate that there are temporal and spatial variations in mannan labeling between cell types in the secondary xylem of Arabidopsis stems. Some similar features of mannan labeling between Arabidopsis and poplar are also discussed.

Keywords

Arabidopsis; Immunolocalization; Interfascicular fiber; LM21 and LM22 antibodies; Mannan; Secondary xylem

Published in

Planta
2012, Volume: 236, number: 5, pages: 1367-1379
Publisher: SPRINGER

SLU Authors

• Kim, Jongsik

  • Department of Forest Products, Swedish University of Agricultural Sciences
    

• Daniel, Geoffrey

  • Department of Forest Products, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Forest Science


Publication identifier

DOI: https://doi.org/10.1007/s00425-012-1687-x

Permanent link to this page (URI)

https://res.slu.se/id/publ/42460